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Kordi N, Saydi A, Karami S, Bagherzadeh-Rahmani B, Marzetti E, Jung F, Stockwell BR. Ferroptosis and aerobic training in ageing: A review. Clin Hemorheol Microcirc 2024:CH232076. [PMID: 38306027 DOI: 10.3233/ch-232076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Ferroptosis is a form of programmed cell death that plays a significant role in causing several diseases such as heart attack and heart failure, through alterations in fat, amino acid, and iron metabolism. Comprehending the regulatory mechanisms of ferroptosis signaling is critical because it has a considerable effect on the elderly's mortality. Conversely, age-related changes in substrate metabolism and metabolite levels are recognized to give rise to obesity. Furthermore, research has proposed that aging and obesity-related changes in substrate metabolism may aggravate ferroptosis. The suppression of ferroptosis holds potential as a successful therapeutic approach for managing different diseases, including sarcopenia, cardiovascular diseases, and central nervous system diseases. However, the pathologic and biological mechanisms behind the function of ferroptosis are not fully comprehended yet. Physical activity could affect lipid, amino acid, and iron metabolism to modulate ferroptosis. The aim of this study is to showcase the current understanding of the molecular mechanisms leading to ferroptosis and discuss the role of aging and physical activity in this phenomenon.
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Affiliation(s)
- Negin Kordi
- Department of Exercise Physiology, Faculty of Sport Sciences, Razi University, Kermanshah, Iran
| | - Ali Saydi
- Department of Exercise Physiology, Faculty of Sport Sciences, Razi University, Kermanshah, Iran
| | - Sajad Karami
- Faculty of Physical Education and Sport Science, Shahid Rajaee Teacher Training University, Tehran, Iran
| | - Behnam Bagherzadeh-Rahmani
- Department of Exercise Physiology, Faculty of Sport Sciences, Hakim Sabzevari University, Sabzevar, Iran
| | - Emanuele Marzetti
- Department of Geriatrics and Orthopedics, Università Cattolica del Sacro Cuore, Rome, Italy; Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Rome, Italy
| | - Friedrich Jung
- Faculty of Health Sciences Brandenburg, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany
| | - Brent R Stockwell
- Department of Chemistry, Columbia University, NewYork, NY, USA; Department of Biological Sciences, Columbia University, New York, NY, USA
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Martinez-Canton M, Galvan-Alvarez V, Garcia-Gonzalez E, Gallego-Selles A, Gelabert-Rebato M, Garcia-Perez G, Santana A, Lopez-Rios L, Vega-Morales T, Martin-Rincon M, Calbet JAL. A Mango Leaf Extract (Zynamite ®) Combined with Quercetin Has Exercise-Mimetic Properties in Human Skeletal Muscle. Nutrients 2023; 15:2848. [PMID: 37447175 DOI: 10.3390/nu15132848] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Zynamite PX®, a mango leaf extract combined with quercetin, enhances exercise performance by unknown molecular mechanisms. Twenty-five volunteers were assigned to a control (17 males) or supplementation group (8 males, receiving 140 mg of Zynamite® + 140 mg quercetin/8 h for 2 days). Then, they performed incremental exercise to exhaustion (IE) followed by occlusion of the circulation in one leg for 60 s. Afterwards, the cuff was released, and a 30 s sprint was performed, followed by 90 s circulatory occlusion (same leg). Vastus lateralis muscle biopsies were obtained at baseline, 20 s after IE (occluded leg) and 10 s after Wingate (occluded leg), and bilaterally at 90 s and 30 min post exercise. Compared to the controls, the Zynamite PX® group showed increased basal protein expression of Thr287-CaMKIIδD (2-fold, p = 0.007) and Ser9-GSK3β (1.3-fold, p = 0.005) and a non-significant increase of total NRF2 (1.7-fold, p = 0.099) and Ser40-NRF2 (1.2-fold, p = 0.061). In the controls, there was upregulation with exercise and recovery of total NRF2, catalase, glutathione reductase, and Thr287-CaMKIIδD (1.2-2.9-fold, all p < 0.05), which was not observed in the Zynamite PX® group. In conclusion, Zynamite PX® elicits muscle signaling changes in resting skeletal muscle resembling those described for exercise training and partly abrogates the stress kinases responses to exercise as observed in trained muscles.
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Affiliation(s)
- Miriam Martinez-Canton
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Victor Galvan-Alvarez
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Eduardo Garcia-Gonzalez
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Angel Gallego-Selles
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Miriam Gelabert-Rebato
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Giovanni Garcia-Perez
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Alfredo Santana
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
- Clinical Genetics Unit, Complejo Hospitalario Universitario Insular-Materno Infantil de Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain
| | - Laura Lopez-Rios
- Nektium Pharma, Las Mimosas 8, Agüimes, 35118 Las Palmas de Gran Canaria, Spain
| | | | - Marcos Martin-Rincon
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
| | - Jose A L Calbet
- Department of Physical Education and Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, Campus Universitario de Tafira s/n, 35017 Las Palmas de Gran Canaria, Spain
- Department of Physical Performance, Norwegian School of Sport Sciences, 0806 Oslo, Norway
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Salimi K, Alvandi M, Saberi Pirouz M, Rakhshan K, Howatson G. Regulating eEF2 and eEF2K in skeletal muscle by exercise. Arch Physiol Biochem 2023:1-12. [PMID: 36633938 DOI: 10.1080/13813455.2023.2164898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 12/15/2022] [Accepted: 12/29/2022] [Indexed: 01/13/2023]
Abstract
Skeletal muscle is a flexible and adaptable tissue that strongly responds to exercise training. The skeletal muscle responds to exercise by increasing muscle protein synthesis (MPS) when energy is available. One of protein synthesis's major rate-limiting and critical regulatory steps is the translation elongation pathway. The process of translation elongation in skeletal muscle is highly regulated. It requires elongation factors that are intensely affected by various physiological stimuli such as exercise and the total available energy of cells. Studies have shown that exercise involves the elongation pathway by numerous signalling pathways. Since the elongation pathway, has been far less studied than the other translation steps, its comprehensive prospect and quantitative understanding remain in the dark. This study highlights the current understanding of the effect of exercise training on the translation elongation pathway focussing on the molecular factors affecting the pathway, including Ca2+, AMPK, PKA, mTORC1/P70S6K, MAPKs, and myostatin. We further discussed the mode and volume of exercise training intervention on the translation elongation pathway.What is the topic of this review? This review summarises the impacts of exercise training on the translation elongation pathway in skeletal muscle focussing on eEF2 and eEF2K.What advances does it highlight? This review highlights mechanisms and factors that profoundly influence the translation elongation pathway and argues that exercise might modulate the response. This review also combines the experimental observations focussing on the regulation of translation elongation during and after exercise. The findings widen our horizon to the notion of mechanisms involved in muscle protein synthesis (MPS) through translation elongation response to exercise training.
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Affiliation(s)
- Kia Salimi
- Department of Exercise Physiology, Faculty of Sport and Exercise Sciences, University of Tehran, Tehran, Iran
| | - Masoomeh Alvandi
- Department of Biological Science in Sport and Health, University of Shahid Beheshti, Tehran, Iran
| | - Mahdi Saberi Pirouz
- Student Research Committee, Iran University of Medical Sciences, Tehran, Iran
| | - Kamran Rakhshan
- Department of Medical Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Electrophysiology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
- Water Research Group, North West University, Potchefstroom, South Africa
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Cis- and trans-resveratrol have opposite effects on histone serine-ADP-ribosylation and tyrosine induced neurodegeneration. Nat Commun 2022; 13:3244. [PMID: 35688816 PMCID: PMC9187644 DOI: 10.1038/s41467-022-30785-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 05/19/2022] [Indexed: 11/08/2022] Open
Abstract
Serum tyrosine levels increase during aging, neurocognitive, metabolic, and cardiovascular disorders. However, calorie restriction (CR) and sleep lower serum tyrosine levels. We previously showed that tyrosine inhibits tyrosyl-tRNA synthetase (TyrRS)-mediated activation of poly-ADP-ribose polymerase 1 (PARP1). Here, we show that histone serine-ADP-ribosylation is decreased in Alzheimer's Disease (AD) brains, and increased tyrosine levels deplete TyrRS and cause neuronal DNA damage. However, dopamine and brain-derived neurotrophic factor (BDNF) increase TyrRS and histone serine-ADP-ribosylation. Furthermore, cis-resveratrol (cis-RSV) that binds to TyrRS mimicking a 'tyrosine-free' conformation increases TyrRS, facilitates histone serine-ADP-ribosylation-dependent DNA repair, and provides neuroprotection in a TyrRS-dependent manner. Conversely, trans-RSV that binds to TyrRS mimicking a 'tyrosine-like' conformation decreases TyrRS, inhibits serine-ADP-ribosylation-dependent DNA repair, and induces neurodegeneration in rat cortical neurons. Our findings suggest that age-associated increase in serum tyrosine levels may effect neurocognitive and metabolic disorders and offer a plausible explanation for divergent results obtained in clinical trials using resveratrol.
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The effects of glucagon and the target of rapamycin (TOR) on skeletal muscle protein synthesis and age-dependent sarcopenia in humans. Clin Nutr ESPEN 2021; 44:15-25. [PMID: 34330459 DOI: 10.1016/j.clnesp.2021.06.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 06/21/2021] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND AIMS Human target of rapamycin (TOR) is a kinase that stimulates protein synthesis in the skeletal muscle in response to amino acids and physical activity. METHODS A comprehensive literature search was conducted on the PubMed database from its inception up to May 2021 to retrieve information on the effects of TOR and glucagon on muscle function. Articles written in English regarding human subjects were included. RESULTS l-leucine activates TOR to initiate protein synthesis in the skeletal muscle. Glucagon has a crucial role suppressing skeletal muscle protein synthesis by increasing l-leucine oxidation and the irreversible loss of this amino acid. Glucagon-induced l-leucine oxidation suppresses TOR and attenuates the ability of skeletal muscle to synthesize proteins. Conditions associated with increased glucagon secretion typically feature reduced ability to synthesize proteins in the skeletal muscle that may evolve into sarcopenia. Animal protein ingestion, unlike vegetable protein, stimulates glucagon secretion. High intake of animal protein increases l-leucine oxidation and promotes the use of amino acids as fuel. Sarcopenia and arterial stiffness characteristically occur together in conditions featuring insulin resistance, such as aging. Insulin resistance mediates the relationship between aging and sarcopenia and arterial stiffness. The loss of skeletal muscle fibers that characterizes sarcopenia is followed by collagen and lipid accumulation. Likewise, insulin resistance is associated with arterial stiffness and intima-media thickening due to adaptive accretion of collagen and lipids in the arterial wall. CONCLUSIONS Human TOR participates in the pathogenesis of sarcopenia and arterial stiffness, although its effects remain to be fully elucidated.
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Dahl MA, Areta JL, Jeppesen PB, Birk JB, Johansen EI, Ingemann-Hansen T, Hansen M, Skålhegg BS, Ivy JL, Wojtaszewski JFP, Overgaard K, Jensen J. Coingestion of protein and carbohydrate in the early recovery phase, compared with carbohydrate only, improves endurance performance despite similar glycogen degradation and AMPK phosphorylation. J Appl Physiol (1985) 2020; 129:297-310. [DOI: 10.1152/japplphysiol.00817.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Endurance athletes competing consecutive days need optimal dietary intake during the recovery period. We report that coingestion of protein and carbohydrate soon after exhaustive exercise, compared with carbohydrate only, resulted in better performance the following day. The better performance after coingestion of protein and carbohydrate was not associated with a higher rate of glycogen synthesis or activation of anabolic signaling compared with carbohydrate only. Importantly, nitrogen balance was positive after coingestion of protein and carbohydrate, which was not the case after intake of carbohydrate only, suggesting that protein synthesis contributes to the better performance the following day.
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Affiliation(s)
- Marius A. Dahl
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
| | - José Lisandro Areta
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | | | - Jesper Bratz Birk
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Egil I. Johansen
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
| | | | - Mette Hansen
- Department of Public Health, Aarhus University, Aarhus C, Denmark
| | - Bjørn Steen Skålhegg
- Department of Nutrition, Division for Molecular Nutrition, University of Oslo, Oslo, Norway
| | - John L. Ivy
- Department of Kinesiology and Health Education, University of Texas at Austin, Austin, Texas
| | - Jørgen F. P. Wojtaszewski
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | | | - Jørgen Jensen
- Department of Physical Performance, Norwegian School of Sports Sciences, Oslo, Norway
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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7
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Saner NJ, Lee MJC, Pitchford NW, Kuang J, Roach GD, Garnham A, Stokes T, Phillips SM, Bishop DJ, Bartlett JD. The effect of sleep restriction, with or without high-intensity interval exercise, on myofibrillar protein synthesis in healthy young men. J Physiol 2020; 598:1523-1536. [PMID: 32078168 PMCID: PMC7217042 DOI: 10.1113/jp278828] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 01/16/2020] [Indexed: 12/23/2022] Open
Abstract
Key points Sleep restriction has previously been associated with the loss of muscle mass in both human and animal models. The rate of myofibrillar protein synthesis (MyoPS) is a key variable in regulating skeletal muscle mass and can be increased by performing high‐intensity interval exercise (HIIE), although the effect of sleep restriction on MyoPS is unknown. In the present study, we demonstrate that participants undergoing a sleep restriction protocol (five nights, with 4 h in bed each night) had lower rates of skeletal muscle MyoPS; however, rates of MyoPS were maintained at control levels by performing HIIE during this period. Our data suggest that the lower rates of MyoPS in the sleep restriction group may contribute to the detrimental effects of sleep loss on muscle mass and that HIIE may be used as an intervention to counteract these effects.
Abstract The present study aimed to investigate the effect of sleep restriction, with or without high‐intensity interval exercise (HIIE), on the potential mechanisms underpinning previously‐reported sleep‐loss‐induced reductions to muscle mass. Twenty‐four healthy, young men underwent a protocol consisting of two nights of controlled baseline sleep and a five‐night intervention period. Participants were allocated into one of three parallel groups, matched for age, V˙O2peak, body mass index and habitual sleep duration; a normal sleep (NS) group [8 h time in bed (TIB) each night], a sleep restriction (SR) group (4 h TIB each night), and a sleep restriction and exercise group (SR+EX, 4 h TIB each night, with three sessions of HIIE). Deuterium oxide was ingested prior to commencing the study and muscle biopsies obtained pre‐ and post‐intervention were used to assess myofibrillar protein synthesis (MyoPS) and molecular markers of protein synthesis and degradation signalling pathways. MyoPS was lower in the SR group [fractional synthetic rate (% day–1), mean ± SD, 1.24 ± 0.21] compared to both the NS (1.53 ± 0.09) and SR+EX groups (1.61 ± 0.14) (P < 0.05). However, there were no changes in the purported regulators of protein synthesis (i.e. p‐AKTser473 and p‐mTORser2448) and degradation (i.e. Foxo1/3 mRNA and LC3 protein) in any group. These data suggest that MyoPS is acutely reduced by sleep restriction, although MyoPS can be maintained by performing HIIE. These findings may explain the sleep‐loss‐induced reductions in muscle mass previously reported and also highlight the potential therapeutic benefit of HIIE to maintain myofibrillar remodelling in this context. Sleep restriction has previously been associated with the loss of muscle mass in both human and animal models. The rate of myofibrillar protein synthesis (MyoPS) is a key variable in regulating skeletal muscle mass and can be increased by performing high‐intensity interval exercise (HIIE), although the effect of sleep restriction on MyoPS is unknown. In the present study, we demonstrate that participants undergoing a sleep restriction protocol (five nights, with 4 h in bed each night) had lower rates of skeletal muscle MyoPS; however, rates of MyoPS were maintained at control levels by performing HIIE during this period. Our data suggest that the lower rates of MyoPS in the sleep restriction group may contribute to the detrimental effects of sleep loss on muscle mass and that HIIE may be used as an intervention to counteract these effects.
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Affiliation(s)
- Nicholas J Saner
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Matthew J-C Lee
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Nathan W Pitchford
- Institute for Health and Sport, Victoria University, Melbourne, Australia.,Sport Performance Optimisation Research Team, School of Human Life Sciences, University of Tasmania, Launceston, Australia
| | - Jujiao Kuang
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Gregory D Roach
- Appleton Institute for Behavioural Science, Central Queensland University, Adelaide, Australia
| | - Andrew Garnham
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Tanner Stokes
- Department of Kinesiology, McMaster University, Hamilton, Canada
| | | | - David J Bishop
- Institute for Health and Sport, Victoria University, Melbourne, Australia.,School of Medical & Health Sciences, Edith Cowan University, Joondalup, Australia
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Theeuwes WF, Gosker HR, Schols AMWJ, Langen RCJ, Remels AHV. Regulation of PGC-1α expression by a GSK-3β-TFEB signaling axis in skeletal muscle. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2020; 1867:118610. [PMID: 31738957 DOI: 10.1016/j.bbamcr.2019.118610] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/30/2019] [Accepted: 11/13/2019] [Indexed: 12/15/2022]
Abstract
OBJECTIVE In muscle cells, the peroxisome proliferator-activated receptor γ co-activator 1 (PGC-1) signaling network, which has been shown to be disturbed in the skeletal muscle in several chronic diseases, tightly controls mitochondrial biogenesis and oxidative substrate metabolism. Previously, we showed that inactivation of glycogen synthase kinase (GSK)-3β potently increased Pgc-1α abundance and oxidative metabolism in skeletal muscle cells. The current study aims to unravel the molecular mechanism driving the increase in Pgc-1α mediated by GSK-3β inactivation. METHODS GSK-3β was inactivated genetically or pharmacologically in C2C12 myotubes and the requirement of transcription factors known to be involved in Pgc-1α transcription for increases in Pgc-1α abundance mediated by inactivation of GSK-3β was examined. RESULTS Enhanced PGC-1α promoter activation after GSK-3β inhibition suggested a transcriptionally-controlled mechanism. While myocyte enhancer factor (MEF)2 transcriptional activity was unaltered, GSK-3β inactivation increased the abundance and activity of the transcription factors estrogen-related receptor (ERR)α and ERRγ. Pharmacological inhibition or knock-down of ERRα and ERRγ however failed to prevent increases in Pgc-1α mRNA mediated by GSK-3β inactivation. Interestingly, GSK-3β inactivation activated transcription factor EB (TFEB), evidenced by decreased phosphorylation and enhanced nuclear localization of the TFEB protein. Moreover, knock-down of TFEB completely prevented increases in Pgc-1α gene expression, PGC-1α promoter activity and PGC-1α protein abundance induced by GSK-3β inactivation. Furthermore, mutation of a specific TFEB binding site on the PGC-1α promoter blocked promoter activation upon inhibition of GSK-3β. CONCLUSIONS In skeletal muscle, GSK-3β inactivation causes dephosphorylation and nuclear translocation of TFEB resulting in TFEB-dependent induction of Pgc-1α expression.
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Affiliation(s)
- W F Theeuwes
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - H R Gosker
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands.
| | - A M W J Schols
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - R C J Langen
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department of Respiratory Medicine, Maastricht University Medical Center+, Maastricht, the Netherlands
| | - A H V Remels
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department of Pharmacology and Toxicology, Maastricht University Medical Center+, Maastricht, the Netherlands
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Macedo AG, Oliveira DMD, Simionato AR. The Influence of the Aerobic Training on Muscle Hypertrophy: Literature Review. JOURNAL OF HEALTH SCIENCES 2019. [DOI: 10.17921/2447-8938.2019v21n4p382-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
AbstractThe literature presents some studies that show that aerobic exercise is responsible for mediating muscle catabolism. Thus, it is interpreted that continuous aerobic exercise produces little or no increase in muscle hypertrophy. The purpose of this review was to demonstrate the effects of aerobic training on muscle hypertrophy alone or in conjunction with resistance training. The present study is characterized by a review of the narrative literature, the databases of SciELO, Google academic and PubMed were consulted. Many studies show that aerobic training (AT) can promote hypertrophic responses in untrained individuals, however, these responses are related to exercise variables such as intensity, volume, frequency, and modality. Higher, continuous or interval intensities, at least 80% of the HRR, seem to be capable of promoting hypertrophic responses when compared to low intensities. In addition, the training volume may also influence this response and different modalities may have a distinct response to muscle hypertrophy. While the combination of TA and resistance training (TR) corresponds to concurrent training (CT), the literature demonstrates that AT in CT can negatively affect acute and chronic hypertrophic responses depending on intensity, volume, mode and training schedule. Keywords: Exercise. Physical Education and Training. Metabolism. ResumoA literatura apresenta alguns estudos que mostram que exercício aeróbio é responsável por mediar o catabolismo muscular. Dessa maneira, interpreta-se que o exercício contínuo aeróbio produz pouco ou nenhum aumento na hipertrofia muscular. O objetivo desta revisão foi demonstrar os efeitos do treinamento aeróbio sobre a hipertrofia muscular de forma isolada ou em conjunto com o treinamento resistido. O presente estudo caracteriza-se um delineamento de revisão de literatura narrativa, foram consultadas as bases de dados do SciELO, Google acadêmico e PubMed. Muitos estudos mostram que o treinamento aeróbio (TA) pode promover respostas hipertróficas em indivíduos não treinados, entretanto, estas respostas estão relacionadas às variáveis do exercícios como intensidade, volume, frequência e modalidade. Intensidades mais altas, contínuas ou intervaladas, no mínimo 80% da FCR, parecem ser capazes de promover respostas hipertróficas quando comparado a baixas intensidades. Além disso, o volume do treinamento também pode influenciar esta resposta e diferentes modalidades podem ter resposta distinta sobre a hipertrofia muscular. Enquanto a combinação do TA com o treinamento resistido (TR) corresponde ao treinamento concorrente (TC), a literatura demonstra que o TA no TC pode interferir negativamente nas respostas hipertróficas de maneira aguda e crônica dependendo da intensidade, volume, modalidade e programação de treinamento. Palavras-chave: Exercício. Educação Física e Treinamento. Metabolismo.
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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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Churchward-Venne TA, Pinckaers PJM, Smeets JSJ, Peeters WM, Zorenc AH, Schierbeek H, Rollo I, Verdijk LB, van Loon LJC. Myofibrillar and Mitochondrial Protein Synthesis Rates Do Not Differ in Young Men Following the Ingestion of Carbohydrate with Milk Protein, Whey, or Micellar Casein after Concurrent Resistance- and Endurance-Type Exercise. J Nutr 2019; 149:198-209. [PMID: 30698725 PMCID: PMC6561606 DOI: 10.1093/jn/nxy244] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 07/17/2018] [Accepted: 08/31/2018] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Whey and micellar casein are high-quality dairy proteins that can stimulate postprandial muscle protein synthesis rates. How whey and casein compare with milk protein in their capacity to stimulate postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis rates during postexercise recovery is currently unknown. OBJECTIVE The objective of this study was to compare postprandial MyoPS and MitoPS rates after protein-carbohydrate co-ingestion with milk protein, whey, or micellar casein during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men. METHODS In a randomized, double-blind, parallel-group design, 48 healthy, young, recreationally active men (mean ± SEM age: 23 ± 0.3 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and L-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 0 g protein (CHO), 20 g milk protein (MILK), 20 g whey protein (WHEY), or 20 g micellar casein protein (CASEIN) after a sequential bout of resistance- and endurance-type exercise (i.e., concurrent exercise). Blood and muscle biopsies were collected over 360 min during recovery from exercise to assess MyoPS and MitoPS rates and signaling through mammalian target of rapamycin complex 1 (mTORC1). RESULTS Despite temporal differences in postprandial plasma leucine concentrations between treatments (P < 0.001), MyoPS rates over 360 min of recovery did not differ between treatments (CHO: 0.049% ± 0.003%/h; MILK: 0.059% ± 0.003%/h; WHEY: 0.054% ± 0.002%/h; CASEIN: 0.059% ± 0.005%/h; P = 0.11). When MILK, WHEY, and CASEIN were pooled into a single group (PROTEIN), protein co-ingestion resulted in greater MyoPS rates compared with CHO (PROTEIN: 0.057% ± 0.002%/h; CHO: 0.049% ± 0.003%/h; P = 0.04). MitoPS rates and signaling through the mTORC1 pathway were similar between treatments. CONCLUSION MyoPS and MitoPS rates do not differ after co-ingestion of either milk protein, whey protein, or micellar casein protein with carbohydrate during recovery from a single bout of concurrent resistance- and endurance-type exercise in recreationally active young men. Co-ingestion of protein with carbohydrate results in greater MyoPS, but not MitoPS rates, when compared with the ingestion of carbohydrate only during recovery from concurrent exercise. This trial was registered at Nederlands Trial Register: NTR5098.
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Affiliation(s)
- Tyler A Churchward-Venne
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Philippe J M Pinckaers
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Joey S J Smeets
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Wouter M Peeters
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Antoine H Zorenc
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Henk Schierbeek
- Department of Pediatrics, Academic Medical Center, Emma Children's Hospital,
Amsterdam, Netherlands
| | - Ian Rollo
- Gatorade Sports Science Institute, Leicester, United Kingdom
| | - Lex B Verdijk
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Luc J C van Loon
- NUTRIM School of Nutrition and Translational Research in Metabolism, Department
of Human Biology, Maastricht University Medical Center+, Maastricht, Netherlands,Address correspondence to LJCvL (e-mail: )
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12
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Xu DP, Jiang SL, Zhao CS, Fang DA, Hu HY. Comparative transcriptomics analysis of the river pufferfish (Takifugu obscurus) by tributyltin exposure: Clues for revealing its toxic injury mechanism. FISH & SHELLFISH IMMUNOLOGY 2018; 82:536-543. [PMID: 30170111 DOI: 10.1016/j.fsi.2018.08.052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/23/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
TBT residual in water had become a noticeable ecological problem for aquatic ecosystems. The river pufferfish (Takifugu obscurus) is a kind of an anadromous fish species and widely distributed in the East China Sea and the Yellow Sea. Because of the water contamination, the pufferfish wild resource had a sudden decline in recent years. Therefore, the study on the response of pufferfish to the TBT exposure may contribute to reveal toxic injury mechanism of T. obscurus under TBT exposure. In this study, the transcriptional library of T. obscurus liver and gill was constructed and sequenced by an improved Illumina HiseqX10 high-throughput sequencing platform under different concentrations of TBT acute stress. The blood cell numbers distinctly decreased after TBT exposure, showing the adverse effects of TBT invasion and self-adjusting ability of the pufferfish. The production of reactive oxygen species increased, demonstrating the oxidation resistance of T. obscurus when exposed to TBT. The obtained data were compared with the genome data of Takifugu rubripes and transcriptional resource database. On this basis, gene function annotation, analysis and classification were carried out by bioinformatics method, and differential genes related to toxic injury function were screened out. Meanwhile, new toxic related genes and related signal pathways were sought to provide new theoretical guidance for the pathogenesis of T. obscurus exposed to TBT. This study not only enriched the transcriptome data of T. obscurus under environmental stress, but also provided a new research method for the response mechanism of T. obscurus under the stimulation of environmental factors.
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Affiliation(s)
- Dong-Po Xu
- Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China; Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, Jiangsu, 214081, China
| | - Shu-Lun Jiang
- Wuxi Fisheries College, Nanjing Agricultural University, Xuejiali 69, Wuxi, 214128, China
| | - Chang-Sheng Zhao
- Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, Jiangsu, 214081, China
| | - Di-An Fang
- Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, Jiangsu, 214081, China
| | - Hao-Yuan Hu
- Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province, College of Life Sciences, Anhui Normal University, Wuhu, Anhui, 241000, China.
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A Brief Review on Concurrent Training: From Laboratory to the Field. Sports (Basel) 2018; 6:sports6040127. [PMID: 30355976 PMCID: PMC6315763 DOI: 10.3390/sports6040127] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 10/14/2018] [Accepted: 10/17/2018] [Indexed: 12/31/2022] Open
Abstract
The majority of sports rely on concurrent training (CT; e.g., the simultaneous training of strength and endurance). However, a phenomenon called “Concurrent training effect” (CTE), which is a compromise in adaptation resulting from concurrent training, appears to be mostly affected by the interference of the molecular pathways of the underlying adaptations from each type of training segments. Until now, it seems that the volume, intensity, type, frequency of endurance training, as well as the training history and background strongly affect the CTE. High volume, moderate, continuous and frequent endurance training, are thought to negatively affect the resistance training-induced adaptations, probably by inhibition of the Protein kinase B—mammalian target of rapamycin pathway activation, of the adenosine monophosphate-activated protein kinase (AMPK). In contrast, it seems that short bouts of high-intensity interval training (HIIT) or sprint interval training (SIT) minimize the negative effects of concurrent training. This is particularly the case when HIIT and SIT incorporated in cycling have even lower or even no negative effects, while they provide at least the same metabolic adaptations, probably through the peroxisome proliferator-activated receptor-γ coactivator (PGC-1a) pathway. However, significant questions about the molecular events underlying the CTE remain unanswered.
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14
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Skeletal Muscle Hypertrophy with Concurrent Exercise Training: Contrary Evidence for an Interference Effect. Sports Med 2017; 46:1029-39. [PMID: 26932769 DOI: 10.1007/s40279-016-0496-y] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Over the last 30+ years, it has become axiomatic that performing aerobic exercise within the same training program as resistance exercise (termed concurrent exercise training) interferes with the hypertrophic adaptations associated with resistance exercise training. However, a close examination of the literature reveals that the interference effect of concurrent exercise training on muscle growth in humans is not as compelling as previously thought. Moreover, recent studies show that, under certain conditions, concurrent exercise may augment resistance exercise-induced hypertrophy in healthy human skeletal muscle. The purpose of this article is to outline the contrary evidence for an acute and chronic interference effect of concurrent exercise on skeletal muscle growth in humans and provide practical literature-based recommendations for maximizing hypertrophy when training concurrently.
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15
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Santos GBD, Oliveira AGD, Gomes Marcondes MCC, Areas MA. Long-term Leucine Supplementation Improves Metabolic But Not Molecular Responses in the Skeletal Muscle of Trained Rats Submitted to Exhaustive Exercise. J Am Coll Nutr 2016; 36:81-87. [PMID: 27938033 DOI: 10.1080/07315724.2016.1183532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
AIM Although there is some evidence of an ergogenic effect of leucine supplementation on acute response to exercise, there is a paucity of information on whether long-term leucine supplementation influences the adaptive response to chronic endurance training and performance. The main aim of our study was to assess the role of long-term leucine supplementation on molecular and metabolic response in skeletal muscle of trained rats after an exhaustion test. METHODS Twenty-four male Wistar rats were randomly allocated into 4 groups. Two of them (control and trained groups) received a balanced control diet (18% protein) and the other 2 (control leucine and trained leucine groups) received a leucine-rich diet (15% protein with 3% leucine) for 6 weeks. The trained groups were submitted to 1 hour of swimming exercise, 5 d/wk for 6 weeks. Three days after the exercise training period, trained groups were submitted to swimming exercise until exhaustion and muscle metabolic and molecular parameters were assessed. RESULTS Endurance training increased citrate synthase activity significantly, whereas exercise until exhaustion increased cytokine levels and led to a lack of activation of phosphorylation of the signaling intermediates assessed. Long-term leucine supplementation enhanced muscle glycogen level in trained rats and citrate synthase activity in sedentary ones. However, it failed to enhance endurance performance of trained rats submitted to an exhaustion test and did not prevent exercise-induced reduction in Akt and mTOR activation. CONCLUSION Long-term leucine supplementation can enhance citrate synthase activity by itself in sedentary individuals and glycogen content when combined with exercise; however, it does not improve endurance performance or prevent Akt and mTOR exercise-induced inhibition.
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Affiliation(s)
- Gustavo Barbosa Dos Santos
- a Department of Structural and Functional Biology , Institute of Biology, University of Campinas (UNICAMP) , Campinas , São Paulo , BRAZIL.,b Sport Science Department , Faculty of Physical Education, Metropolitan College of Campinas (Metrocamp) , Campinas, São Paulo , BRAZIL
| | - André Gustavo de Oliveira
- a Department of Structural and Functional Biology , Institute of Biology, University of Campinas (UNICAMP) , Campinas , São Paulo , BRAZIL
| | | | - Miguel Arcanjo Areas
- a Department of Structural and Functional Biology , Institute of Biology, University of Campinas (UNICAMP) , Campinas , São Paulo , BRAZIL
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16
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HAMMOND KELLYM, IMPEY SAMUELG, CURRELL KEVIN, MITCHELL NIGEL, SHEPHERD SAMO, JEROMSON STEWART, HAWLEY JOHNA, CLOSE GRAEMEL, HAMILTON LEED, SHARPLES ADAMP, MORTON JAMESP. Postexercise High-Fat Feeding Suppresses p70S6K1 Activity in Human Skeletal Muscle. Med Sci Sports Exerc 2016; 48:2108-2117. [DOI: 10.1249/mss.0000000000001009] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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17
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Impey SG, Hammond KM, Shepherd SO, Sharples AP, Stewart C, Limb M, Smith K, Philp A, Jeromson S, Hamilton DL, Close GL, Morton JP. Fuel for the work required: a practical approach to amalgamating train-low paradigms for endurance athletes. Physiol Rep 2016; 4:4/10/e12803. [PMID: 27225627 PMCID: PMC4886170 DOI: 10.14814/phy2.12803] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/29/2016] [Indexed: 01/09/2023] Open
Abstract
Using an amalgamation of previously studied "train-low" paradigms, we tested the effects of reduced carbohydrate (CHO) but high leucine availability on cell-signaling responses associated with exercise-induced regulation of mitochondrial biogenesis and muscle protein synthesis (MPS). In a repeated-measures crossover design, 11 males completed an exhaustive cycling protocol with high CHO availability before, during, and after exercise (HIGH) or alternatively, low CHO but high protein (leucine enriched) availability (LOW + LEU). Muscle glycogen was different (P < 0.05) pre-exercise (HIGH: 583 ± 158, LOW + LEU: 271 ± 85 mmol kg(-1) dw) but decreased (P < 0.05) to comparable levels at exhaustion (≈100 mmol kg(-1) dw). Despite differences (P < 0.05) in exercise capacity (HIGH: 158 ± 29, LOW + LEU: 100 ± 17 min), exercise induced (P < 0.05) comparable AMPKα2 (3-4-fold) activity, PGC-1α (13-fold), p53 (2-fold), Tfam (1.5-fold), SIRT1 (1.5-fold), Atrogin 1 (2-fold), and MuRF1 (5-fold) gene expression at 3 h post-exercise. Exhaustive exercise suppressed p70S6K activity to comparable levels immediately post-exercise (≈20 fmol min(-1) mg(-1)). Despite elevated leucine availability post-exercise, p70S6K activity remained suppressed (P < 0.05) 3 h post-exercise in LOW + LEU (28 ± 14 fmol min(-1) mg(-1)), whereas muscle glycogen resynthesis (40 mmol kg(-1) dw h(-1)) was associated with elevated (P < 0.05) p70S6K activity in HIGH (53 ± 30 fmol min(-1) mg(-1)). We conclude: (1) CHO restriction before and during exercise induces "work-efficient" mitochondrial-related cell signaling but; (2) post-exercise CHO and energy restriction maintains p70S6K activity at basal levels despite feeding leucine-enriched protein. Our data support the practical concept of "fuelling for the work required" as a potential strategy for which to amalgamate train-low paradigms into periodized training programs.
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Affiliation(s)
- Samuel G Impey
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Kelly M Hammond
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Sam O Shepherd
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Adam P Sharples
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Claire Stewart
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Marie Limb
- MRC-ARUK Centre for Musculoskeletal Aging, Research Division of Medical Sciences and Graduate Entry Medicine, School of Medicine Faculty of Medicine and Health Sciences, University of Nottingham Royal Derby Hospital Centre, Derby, UK
| | - Kenneth Smith
- MRC-ARUK Centre for Musculoskeletal Aging, Research Division of Medical Sciences and Graduate Entry Medicine, School of Medicine Faculty of Medicine and Health Sciences, University of Nottingham Royal Derby Hospital Centre, Derby, UK
| | - Andrew Philp
- MRC-ARUK Centre for Musculoskeletal Aging Research, School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Stewart Jeromson
- Health and Exercise Sciences Research Group, University of Stirling, Stirling, UK
| | - D Lee Hamilton
- Health and Exercise Sciences Research Group, University of Stirling, Stirling, UK
| | - Graeme L Close
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - James P Morton
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
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18
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Coffey VG, Hawley JA. Concurrent exercise training: do opposites distract? J Physiol 2016; 595:2883-2896. [PMID: 27506998 DOI: 10.1113/jp272270] [Citation(s) in RCA: 163] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 08/05/2016] [Indexed: 12/19/2022] Open
Abstract
Specificity is a core principle of exercise training to promote the desired adaptations for maximising athletic performance. The principle of specificity of adaptation is underpinned by the volume, intensity, frequency and mode of contractile activity and is most evident when contrasting the divergent phenotypes that result after undertaking either prolonged endurance or resistance training. The molecular profiles that generate the adaptive response to different exercise modes have undergone intense scientific scrutiny. Given divergent exercise induces similar signalling and gene expression profiles in skeletal muscle of untrained or recreationally active individuals, what is currently unclear is how the specificity of the molecular response is modified by prior training history. The time course of adaptation and when 'phenotype specificity' occurs has important implications for exercise prescription. This context is essential when attempting to concomitantly develop resistance to fatigue (through endurance-based exercise) and increased muscle mass (through resistance-based exercise), typically termed 'concurrent training'. Chronic training studies provide robust evidence that endurance exercise can attenuate muscle hypertrophy and strength but the mechanistic underpinning of this 'interference' effect with concurrent training is unknown. Moreover, despite the potential for several key regulators of muscle metabolism to explain an incompatibility in adaptation between endurance and resistance exercise, it now seems likely that multiple integrated, rather than isolated, effectors or processes generate the interference effect. Here we review studies of the molecular responses in skeletal muscle and evidence for the interference effect with concurrent training within the context of the specificity of training adaptation.
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Affiliation(s)
- Vernon G Coffey
- Bond Institute of Health & Sport and Faculty of Health Sciences & Medicine, Bond University, Gold Coast, Queensland, 4226, Australia
| | - John A Hawley
- Centre for Exercise and Nutrition, Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, Melbourne, Victoria, 3065, Australia.,Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
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20
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Bae JY, Shin KO, Woo J, Woo SH, Jang KS, Lee YH, Kang S. Exercise and dietary change ameliorate high fat diet induced obesity and insulin resistance via mTOR signaling pathway. J Exerc Nutrition Biochem 2016; 20:28-33. [PMID: 27508151 PMCID: PMC4977908 DOI: 10.20463/jenb.2016.06.20.2.4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 04/25/2016] [Accepted: 05/23/2016] [Indexed: 12/11/2022] Open
Abstract
[Purpose] The purpose of this study was to investigate the effect of exercise and dietary change on obesity and insulin resistance and mTOR signaling protein levels in skeletal muscles of obese rats. [Methods] Sixty male Sprague-Dawley rats were divided into CO (Normal diet) and HF (High Fat diet) groups in order to induce obesity for 15 weeks. The rats were then subdivided into CO, COT (CO + Training), HF, HFT (HF + Training), HFND (Dietary change), and HFNDT (HFND + Training) groups (10 rats / group). The training groups underwent moderate-intensity treadmill exercise for 8 weeks, after which soleus muscles were excised and analyzed. Data was statistically analyzed by independent t-test and One-way ANOVA tests with a 0.05 significance level. [Results] Fasting blood glucose, plasma insulin, and HOMA-IR in the HF group were significantly higher, as compared with other groups (p <.05). Protein levels of insulin receptor subunit-1 (IRS-1), IRS-2, and p-Akt were significantly higher in the HFT, HFND, and HFNDT groups, as compared with HF group. In addition, the protein levels of the mammalian target of rapamycin complex 1 (mTORC1) and ribosomal S6 protein kinase 1 were significantly decreased by exercise and dietary change (p <.05). However, mTORC2 and phosphoinositide 3-kinase were significantly increased (p <.05). [Conclusion] In summary, despite the negative impact of continuous high fat intake, regular exercise and dietary change showed a positive effect on insulin resistance and mTOR signaling protein levels.
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Affiliation(s)
- Ju Yong Bae
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan Republic of Korea
| | - Ki Ok Shin
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan Republic of Korea
| | - Jinhee Woo
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan Republic of Korea
| | - Sang Heon Woo
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan Republic of Korea
| | - Ki Soeng Jang
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan Republic of Korea
| | - Yul Hyo Lee
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan Republic of Korea
| | - Sunghwun Kang
- Laboratory of Exercise physiology, Division of Sport Science, Kangwon National University, Chuncheon Republic of Korea
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21
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Philp A, Schenk S, Perez-Schindler J, Hamilton DL, Breen L, Laverone E, Jeromson S, Phillips SM, Baar K. Rapamycin does not prevent increases in myofibrillar or mitochondrial protein synthesis following endurance exercise. J Physiol 2016; 593:4275-84. [PMID: 26227152 DOI: 10.1113/jp271219] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 07/20/2015] [Indexed: 01/20/2023] Open
Abstract
The present study aimed to investigate the role of the mechanistic target of rapamycin complex 1 (mTORC1) in the regulation of myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis following endurance exercise. Forty-two female C57BL/6 mice performed 1 h of treadmill running (18 m min(-1) ; 5° grade), 1 h after i.p. administration of rapamycin (1.5 mg · kg(-1) ) or vehicle. To quantify skeletal muscle protein fractional synthesis rates, a flooding dose (50 mg · kg(-1) ) of l-[ring-(13) C6 ]phenylalanine was administered via i.p. injection. Blood and gastrocnemius muscle were collected in non-exercised control mice, as well as at 0.5, 3 and 6 h after completing exercise (n = 4 per time point). Skeletal muscle MyoPS and MitoPS were determined by measuring isotope incorporation in their respective protein pools. Activation of the mTORC1-signalling cascade was measured via direct kinase activity assay and immunoblotting, whereas genes related to mitochondrial biogenesis were measured via a quantitative RT-PCR. MyoPS increased rapidly in the vehicle group post-exercise and remained elevated for 6 h, whereas this response was transiently blunted (30 min post-exercise) by rapamycin. By contrast, MitoPS was unaffected by rapamycin, and was increased over the entire post-exercise recovery period in both groups (P < 0.05). Despite rapid increases in both MyoPS and MitoPS, mTORC1 activation was suppressed in both groups post-exercise for the entire 6 h recovery period. Peroxisome proliferator activated receptor-γ coactivator-1α, pyruvate dehydrogenase kinase 4 and mitochondrial transcription factor A mRNA increased post-exercise (P < 0.05) and this response was augmented by rapamycin (P < 0.05). Collectively, these data suggest that endurance exercise stimulates MyoPS and MitoPS in skeletal muscle independently of mTORC1 activation.
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Affiliation(s)
- Andrew Philp
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.,Neurobiology, Physiology and Behaviour, University of California, Davis, CA, USA
| | - Simon Schenk
- Department of Orthopaedic Surgery and Biomedical Sciences Graduate Program, University of California, San Diego, CA, USA
| | - Joaquin Perez-Schindler
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | | | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.,Department of Kinesiology, McMaster University, Hamilton, ON, CA
| | - Erin Laverone
- Neurobiology, Physiology and Behaviour, University of California, Davis, CA, USA
| | | | | | - Keith Baar
- Neurobiology, Physiology and Behaviour, University of California, Davis, CA, USA
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22
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Dantas WS, Marcondes JAM, Shinjo SK, Perandini LA, Zambelli VO, Neves WD, Barcellos CRG, Rocha MP, Yance VDRV, Pereira RTDS, Murai IH, Pinto ALDS, Roschel H, Gualano B. GLUT4 translocation is not impaired after acute exercise in skeletal muscle of women with obesity and polycystic ovary syndrome. Obesity (Silver Spring) 2015; 23:2207-15. [PMID: 26373822 DOI: 10.1002/oby.21217] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 06/09/2015] [Accepted: 06/11/2015] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The aim of this study was to examine the effects of acute exercise on insulin signaling in skeletal muscle of women with polycystic ovary syndrome (PCOS) and controls (CTRL). METHODS Fifteen women with obesity and PCOS and 12 body mass index-matched CTRL participated in this study. Subjects performed a 40-min single bout of exercise. Muscle biopsies were performed before and 60 min after exercise. Selected proteins were assessed by Western blotting. RESULTS CTRL, but not PCOS, showed a significant increase in PI3-k p85 and AS160 Thr 642 after a single bout of exercise (P = 0.018 and P = 0.018, respectively). Only PCOS showed an increase in Akt Thr 308 and AMPK phosphorylation after exercise (P = 0.018 and P = 0.018, respectively). Total GLUT4 expression was comparable between groups (P > 0.05). GLUT4 translocation tended to be significantly higher in both groups after exercise (PCOS: P = 0.093; CTRL: P = 0.091), with no significant difference between them (P > 0.05). CONCLUSIONS A single bout of exercise elicited similar GLUT4 translocation in skeletal muscle of PCOS and CTRL, despite a slightly differential pattern of protein phosphorylation. The absence of impairment in GLUT4 translocation suggests that PCOS patients with obesity and insulin resistance may benefit from exercise training.
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Affiliation(s)
- Wagner Silva Dantas
- School of Physical Education and Sport, Department of Biodynamic of Human Movement, University of Sao Paulo, Brazil
| | | | | | | | | | - Willian Das Neves
- School of Physical Education and Sport, Department of Biodynamic of Human Movement, University of Sao Paulo, Brazil
| | | | | | | | | | - Igor Hisashi Murai
- School of Physical Education and Sport, Department of Biodynamic of Human Movement, University of Sao Paulo, Brazil
| | - Ana Lucia De Sá Pinto
- Rheumatology Division, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Hamilton Roschel
- School of Physical Education and Sport, Department of Biodynamic of Human Movement, University of Sao Paulo, Brazil
- Rheumatology Division, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Bruno Gualano
- School of Physical Education and Sport, Department of Biodynamic of Human Movement, University of Sao Paulo, Brazil
- Rheumatology Division, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
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23
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Trewin AJ, Lundell LS, Perry BD, Patil KV, Chibalin AV, Levinger I, McQuade LR, Stepto NK. Effect of N-acetylcysteine infusion on exercise-induced modulation of insulin sensitivity and signaling pathways in human skeletal muscle. Am J Physiol Endocrinol Metab 2015; 309:E388-97. [PMID: 26105008 DOI: 10.1152/ajpendo.00605.2014] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 06/16/2015] [Indexed: 01/10/2023]
Abstract
-Reactive oxygen species (ROS) produced in skeletal muscle may play a role in potentiating the beneficial responses to exercise; however, the effects of exercise-induced ROS on insulin action and protein signaling in humans has not been fully elucidated. Seven healthy, recreationally active participants volunteered for this double-blind, randomized, repeated-measures crossover study. Exercise was undertaken with infusion of saline (CON) or the antioxidant N-acetylcysteine (NAC) to attenuate ROS. Participants performed two 1-h cycling exercise sessions 7-14 days apart, 55 min at 65% V̇o2peak plus 5 min at 85%V̇o2peak, followed 3 h later by a 2-h hyperinsulinemic euglycemic clamp (40 mIU·min(-1)·m(2)) to determine insulin sensitivity. Four muscle biopsies were taken on each trial day, at baseline before NAC infusion (BASE), after exercise (EX), after 3-h recovery (REC), and post-insulin clamp (PI). Exercise, ROS, and insulin action on protein phosphorylation were evaluated with immunoblotting. NAC tended to decrease postexercise markers of the ROS/protein carbonylation ratio by -13.5% (P = 0.08) and increase the GSH/GSSG ratio twofold vs. CON (P < 0.05). Insulin sensitivity was reduced (-5.9%, P < 0.05) by NAC compared with CON without decreased phosphorylation of Akt or AS160. Whereas p-mTOR was not significantly decreased by NAC after EX or REC, phosphorylation of the downstream protein synthesis target kinase p70S6K was blunted by 48% at PI with NAC compared with CON (P < 0.05). We conclude that NAC infusion attenuated muscle ROS and postexercise insulin sensitivity independent of Akt signaling. ROS also played a role in normal p70S6K phosphorylation in response to insulin stimulation in human skeletal muscle.
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Affiliation(s)
- Adam J Trewin
- College of Sport and Exercise Science and Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Victoria, Australia
| | | | - Ben D Perry
- College of Sport and Exercise Science and Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Victoria, Australia
| | | | | | - Itamar Levinger
- College of Sport and Exercise Science and Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Victoria, Australia
| | - Leon R McQuade
- Australian Proteome Analysis Facility, Macquarie University, Sydney, New South Wales, Australia
| | - Nigel K Stepto
- College of Sport and Exercise Science and Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Victoria, Australia;
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Shin KO, Bae JY, Woo J, Jang KS, Kim KS, Park JS, Kim IK, Kang S. The effect of exercise on expression of myokine and angiogenesis mRNA in skeletal muscle of high fat diet induced obese rat. J Exerc Nutrition Biochem 2015; 19:91-8. [PMID: 26244127 PMCID: PMC4523810 DOI: 10.5717/jenb.2015.15061006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 06/03/2015] [Accepted: 06/10/2015] [Indexed: 11/04/2022] Open
Abstract
PURPOSE The purpose of this study was to investigate the effect of regular treadmill exercise on the mRNA expressions of myokines and angiogenesis factors in the skeletal muscle of obese rats. METHODS Thirty two male Sprague-Dawley rats (4weeks old) were divided into the CO (control) and HF (high fat diet) groups. Obesity was induced in the HF group by consumption of 45% high-fat diet for 15 weeks. These groups were further subdivided into training groups (COT and HFT); the training groups conducted moderate intensity treadmill training for 8 weeks. Soleus muscles were excised and analyzed by real-time quantitative PCR. RESULTS mRNA expression of myokines, such as PGC-1α, IL-6, and IL-15, in the COT and HFT groups (which conducted regular exercise), were higher as compared with the CO and HF groups (p < 0.05). Also, the levels in the HF group were significantly lower when compared with CO group (p < 0.05). Expression of angiogenesis mRNA, namely mTOR, VEGF, and FLT1, were significantly lower in the HF group, as compared to the CO group (p < 0.05). In addition, COT group had a higher expression of mTORC1, mTORC2, VEGF and FLT mRNA, than the CO group (p < 0.05); the HFT group also had higher expressions of mTOR, VEGF and FLT1 mRNA than the HF group (p < 0.05). CONCLUSION These results indicate that mRNA expression of myokines was increased through the activity of muscle contraction, and it also promoted the mRNA expression of angiogenesis due to activation of mTOR. Thus, we conclude that not only under normal health conditions, but in obesity and excess nutritional circumstances also, regular exercise seems to act positively on the glycemic control and insulin sensitivity through the angiogenesis signaling pathway.
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Affiliation(s)
- Ki Ok Shin
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea
| | - Ju Yong Bae
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea
| | - Jinhee Woo
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea
| | - Ki Soeng Jang
- Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea
| | - Keun Su Kim
- Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea
| | - Jung Sub Park
- Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea
| | - In Ki Kim
- Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea
| | - Sunghwun Kang
- Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea
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Ozaki H, Loenneke J, Thiebaud R, Abe T. Cycle training induces muscle hypertrophy and strength gain: strategies and mechanisms. ACTA ACUST UNITED AC 2015; 102:1-22. [DOI: 10.1556/aphysiol.102.2015.1.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Ozaki H, Abe T, Mikesky AE, Sakamoto A, Machida S, Naito H. Physiological stimuli necessary for muscle hypertrophy. ACTA ACUST UNITED AC 2015. [DOI: 10.7600/jpfsm.4.43] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Hayao Ozaki
- Japan Society for the Promotion of Science
- Graduate School of Medicine, Juntendo University
- Graduate School of Health and Sport Science, Juntendo University
| | - Takashi Abe
- Department of Health, Exercise Science & Recreation Management, The University of Mississippi
| | - Alan E. Mikesky
- School of Physical Education and Tourism Management, Indiana University Purdue University Indianapolis
| | - Akihiro Sakamoto
- Institute of Health and Sports Science & Medicine, Juntendo University
| | - Shuichi Machida
- Graduate School of Health and Sport Science, Juntendo University
| | - Hisashi Naito
- Graduate School of Health and Sport Science, Juntendo University
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Interference between concurrent resistance and endurance exercise: molecular bases and the role of individual training variables. Sports Med 2014; 44:743-62. [PMID: 24728927 DOI: 10.1007/s40279-014-0162-1] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Concurrent training is defined as simultaneously incorporating both resistance and endurance exercise within a periodized training regime. Despite the potential additive benefits of combining these divergent exercise modes with regards to disease prevention and athletic performance, current evidence suggests that this approach may attenuate gains in muscle mass, strength, and power compared with undertaking resistance training alone. This has been variously described as the interference effect or concurrent training effect. In recent years, understanding of the molecular mechanisms mediating training adaptation in skeletal muscle has emerged and provided potential mechanistic insight into the concurrent training effect. Although it appears that various molecular signaling responses induced in skeletal muscle by endurance exercise can inhibit pathways regulating protein synthesis and stimulate protein breakdown, human studies to date have not observed such molecular 'interference' following acute concurrent exercise that might explain compromised muscle hypertrophy following concurrent training. However, given the multitude of potential concurrent training variables and the limitations of existing evidence, the potential roles of individual training variables in acute and chronic interference are not fully elucidated. The present review explores current evidence for the molecular basis of the specificity of training adaptation and the concurrent interference phenomenon. Additionally, insights provided by molecular and performance-based concurrent training studies regarding the role of individual training variables (i.e., within-session exercise order, between-mode recovery, endurance training volume, intensity, and modality) in the concurrent interference effect are discussed, along with the limitations of our current understanding of this complex paradigm.
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28
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Hayasaka M, Tsunekawa H, Yoshinaga M, Murakami T. Endurance exercise induces REDD1 expression and transiently decreases mTORC1 signaling in rat skeletal muscle. Physiol Rep 2014; 2:2/12/e12254. [PMID: 25539833 PMCID: PMC4332227 DOI: 10.14814/phy2.12254] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Working muscle conserves adenosine triphosphate (ATP) for muscle contraction by attenuating protein synthesis through several different pathways. Regulated in development and DNA damage response 1 (REDD1) is one candidate protein that can itself attenuate muscle protein synthesis during muscle contraction. In this study, we investigated whether endurance exercise induces REDD1 expression in association with decreased mammalian target of rapamycin (mTOR) complex I (mTORC1) signaling and global protein synthesis in rat skeletal muscle. After overnight fasting, rats ran on a treadmill at a speed of 28 m/min for 60 min, and were killed before and immediately, 1, 3, 6, 12, and 24 h after exercise. REDD1 mRNA and corresponding protein levels increased rapidly immediately after exercise, and gradually decreased back to the basal level over a period of 6 h in the gastrocnemius muscle. Phosphorylation of mTOR Ser2448 and S6K1 Thr389 increased with the exercise, but diminished in 1–3 h into the recovery period after cessation of exercise. The rate of protein synthesis, as determined by the surface sensing of translation (SUnSET) method, was not altered by exercise in fasted muscle. These results suggest that REDD1 attenuates exercise‐induced mTORC1 signaling. This may be one mechanism responsible for blunting muscle protein synthesis during exercise and in the early postexercise recovery period. We show that REDD1 expression is rapidly induced by an acute bout of endurance exercise in association with a decrease in mTORC1 signaling in rat muscle. The rate of mixed‐muscle protein synthesis was, however, not altered by exercise in fasted state. These results suggest that REDD1‐induced suppression of mTORC1 signaling may be one mechanism to blunt muscle protein synthesis during exercise and postexercise early recovery period.
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Affiliation(s)
- Miki Hayasaka
- Department of Nutrition, Shigakkan University, Yokone-Machi, Ohbu, Japan
| | - Haruka Tsunekawa
- Department of Nutrition, Shigakkan University, Yokone-Machi, Ohbu, Japan
| | - Mariko Yoshinaga
- Department of Nutrition, Shigakkan University, Yokone-Machi, Ohbu, Japan
| | - Taro Murakami
- Department of Nutrition, Shigakkan University, Yokone-Machi, Ohbu, Japan
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Sato T, Ito Y, Nagasawa T. Lysine suppresses myofibrillar protein degradation by regulating the autophagic-lysosomal system through phosphorylation of Akt in C2C12 cells. SPRINGERPLUS 2014; 3:584. [PMID: 25332884 PMCID: PMC4197202 DOI: 10.1186/2193-1801-3-584] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 10/01/2014] [Indexed: 12/21/2022]
Abstract
The prevention of muscle wasting is important for maintaining quality of life, since loss of muscle mass can lead to a bedridden state and decreased resistance to diseases. The prevention of muscle wasting requires an increase in protein synthesis and a decrease in protein degradation in skeletal muscle. We previously showed that lysine (Lys) markedly suppressed myofibrillar protein degradation by inhibiting the autophagic-lysosomal system via the mammalian target of rapamycin (mTOR) and other signal molecules in C2C12 cells. In this study, we investigated the involvement of Akt and adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK), two regulators of autophagy, on the suppressive effects of Lys on myofibrillar protein degradation in C2C12 cells. Lys induced the phosphorylation of Akt, but the suppressive effects of Lys on myofibrillar protein degradation and autophagy were completely abolished in the presence of Akt1/2 kinase inhibitor (Akti). Lys suppressed the phosphorylation of AMPK, but this effect was also abolished by Akti. On the other hand, AMPK activation by 5-aminoimidazole-4-carboxamide-1-β-D-ribonucleoside (AICAR) did not affect either Akt activity or the autophagic-lysosomal system in C2C12 cells treated with Lys. These results indicate that regulation of AMPK activity is not essential for the regulation of autophagy by Lys. Taken together, our results show that Lys suppresses myofibrillar protein degradation by the autophagic-lysosomal system through the phosphorylation of Akt in C2C12 cells.
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Affiliation(s)
- Tomonori Sato
- Department of Bioresources Science, The United Graduate School of Agricultural Sciences, Iwate University, Morioka, Iwate 020-8550 Japan
| | - Yoshiaki Ito
- Department of Biological Chemistry and Food Science, Graduate School of Agriculture, Iwate University, Morioka, Iwate 020-8550 Japan
| | - Takashi Nagasawa
- Department of Biological Chemistry and Food Science, Graduate School of Agriculture, Iwate University, Morioka, Iwate 020-8550 Japan
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Sato T, Ito Y, Nagasawa T. Regulation of skeletal muscle protein degradation and synthesis by oral administration of lysine in rats. J Nutr Sci Vitaminol (Tokyo) 2014; 59:412-9. [PMID: 24418875 DOI: 10.3177/jnsv.59.412] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Several catabolic diseases and unloading induce muscle mass wasting, which causes severe pathological progression in various diseases and aging. Leucine is known to attenuate muscle loss via stimulation of protein synthesis and suppression of protein degradation in skeletal muscle. The aim of this study was to investigate the effects of lysine intake on protein degradation and synthesis in skeletal muscle. Fasted rats were administered 22.8-570 mg Lys/100 g body weight and the rates of myofibrillar protein degradation were assessed for 0-6 h after Lys administration. The rates of myofibrillar protein degradation evaluated by MeHis release from the isolated muscles were markedly suppressed after administration of 114 mg Lys/100 g body weight and of 570 mg Lys/100 g body weight. LC3-II, a marker of the autophagic-lysosomal pathway, tended to decrease (p=0.05, 0.08) after Lys intake (114 mg/100 g body weight). However, expression of ubiquitin ligase E3 atrogin-1 mRNA and levels of ubiquitinated proteins were not suppressed by Lys intake. Phosphorylation levels of mTOR, S6K1 and 4E-BP1 in the gastrocnemius muscle were not altered after Lys intake. These results suggest that Lys is able to suppress myofibrillar protein degradation at least partially through the autophagic-lysosomal pathway, not the ubiquitin-proteasomal pathway, whereas Lys might be unable to stimulate protein synthesis within this time frame.
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Affiliation(s)
- Tomonori Sato
- Biological Chemistry and Food Science, Graduate School of Agriculture, Iwate University
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31
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Sanchez AMJ, Bernardi H, Py G, Candau RB. Autophagy is essential to support skeletal muscle plasticity in response to endurance exercise. Am J Physiol Regul Integr Comp Physiol 2014; 307:R956-69. [PMID: 25121614 DOI: 10.1152/ajpregu.00187.2014] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Physical exercise is a stress that can substantially modulate cellular signaling mechanisms to promote morphological and metabolic adaptations. Skeletal muscle protein and organelle turnover is dependent on two major cellular pathways: Forkhead box class O proteins (FOXO) transcription factors that regulate two main proteolytic systems, the ubiquitin-proteasome, and the autophagy-lysosome systems, including mitochondrial autophagy, and the MTORC1 signaling associated with protein translation and autophagy inhibition. In recent years, it has been well documented that both acute and chronic endurance exercise can affect the autophagy pathway. Importantly, substantial efforts have been made to better understand discrepancies in the literature on its modulation during exercise. A single bout of endurance exercise increases autophagic flux when the duration is long enough, and this response is dependent on nutritional status, since autophagic flux markers and mRNA coding for actors involved in mitophagy are more abundant in the fasted state. In contrast, strength and resistance exercises preferentially raise ubiquitin-proteasome system activity and involve several protein synthesis factors, such as the recently characterized DAGK for mechanistic target of rapamycin activation. In this review, we discuss recent progress on the impact of acute and chronic exercise on cell component turnover systems, with particular focus on autophagy, which until now has been relatively overlooked in skeletal muscle. We especially highlight the most recent studies on the factors that can impact its modulation, including the mode of exercise and the nutritional status, and also discuss the current limitations in the literature to encourage further works on this topic.
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Affiliation(s)
- Anthony M J Sanchez
- Department of Critical Care, McGill University Health Centre and Meakins-Christie Laboratories, Department of Medicine, McGill University, Montreal, Quebec, Canada; University of Perpignan Via Domitia, Laboratoire Performance Santé Altitude, EA 4604, Font-Romeu, France;
| | - Henri Bernardi
- Institut National de la Recherche Agronomique, UMR 866 Dynamique Musculaire et Métabolisme, Montpellier, France; and
| | - Guillaume Py
- Faculty of Sport Sciences, University of Montpellier 1, Montpellier, France
| | - Robin B Candau
- Faculty of Sport Sciences, University of Montpellier 1, Montpellier, France
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Stefanetti RJ, Lamon S, Wallace M, Vendelbo MH, Russell AP, Vissing K. Regulation of ubiquitin proteasome pathway molecular markers in response to endurance and resistance exercise and training. Pflugers Arch 2014; 467:1523-1537. [DOI: 10.1007/s00424-014-1587-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/02/2014] [Accepted: 07/24/2014] [Indexed: 12/30/2022]
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Di Donato DM, West DWD, Churchward-Venne TA, Breen L, Baker SK, Phillips SM. Influence of aerobic exercise intensity on myofibrillar and mitochondrial protein synthesis in young men during early and late postexercise recovery. Am J Physiol Endocrinol Metab 2014; 306:E1025-32. [PMID: 24595306 PMCID: PMC4010655 DOI: 10.1152/ajpendo.00487.2013] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Aerobic exercise is typically associated with expansion of the mitochondrial protein pool and improvements in muscle oxidative capacity. The impact of aerobic exercise intensity on the synthesis of specific skeletal muscle protein subfractions is not known. We aimed to study the effect of aerobic exercise intensity on rates of myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis over an early (0.5-4.5 h) and late (24-28 h) period during postexercise recovery. Using a within-subject crossover design, eight males (21 ± 1 yr, Vo2peak 46.7 ± 2.0 ml·kg(-1)·min(-1)) performed two work-matched cycle ergometry exercise trials (LOW: 60 min at 30% Wmax; HIGH: 30 min at 60% Wmax) in the fasted state while undergoing a primed constant infusion of l-[ring-(13)C6]phenylalanine. Muscle biopsies were obtained at rest and 0.5, 4.5, 24, and 28 h postexercise to determine both the "early" and "late" response of MyoPS and MitoPS and the phosphorylation status of selected proteins within both the Akt/mTOR and MAPK pathways. Over 24-28 h postexercise, MitoPS was significantly greater after the HIGH vs. LOW exercise trial (P < 0.05). Rates of MyoPS were increased equivalently over 0.5-4.5 h postexercise recovery (P < 0.05) but remained elevated at 24-28 h postexercise only following the HIGH trial. In conclusion, an acute bout of high- but not low-intensity aerobic exercise in the fasted state resulted in a sustained elevation of both MitoPS and MyoPS at 24-28 h postexercise recovery.
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Lundberg TR, Fernandez-Gonzalo R, Tesch PA. Exercise-induced AMPK activation does not interfere with muscle hypertrophy in response to resistance training in men. J Appl Physiol (1985) 2014; 116:611-20. [DOI: 10.1152/japplphysiol.01082.2013] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
As aerobic exercise (AE) may interfere with adaptations to resistance exercise (RE), this study explored acute and chronic responses to consecutive AE (∼45 min cycling) and RE (4 × 7 maximal knee extensions) vs. RE only. Ten men performed acute unilateral AE + RE interspersed by 15 min recovery. The contralateral leg was subjected to RE. This exercise paradigm was then implemented in a 5-wk training program. Protein phosphorylation, gene expression, and glycogen content were assessed in biopsies obtained from the vastus lateralis muscle of both legs immediately before and 3 h after acute RE. Quadriceps muscle size and in vivo torque were measured, and muscle samples were analyzed for citrate synthase activity and glycogen concentration, before and after training. Acute AE reduced glycogen content (32%; P < 0.05) and increased ( P < 0.05) phosphorylation of AMPK (1.5-fold) and rpS6 (1.3-fold). Phosphorylation of p70S6K and 4E-BP1 remained unchanged. Myostatin gene expression was downregulated after acute AE + RE but not RE. Muscle size showed greater ( P < 0.05) increase after AE + RE (6%) than RE (3%) training. Citrate synthase activity (18%) and endurance performance (22%) increased ( P < 0.05) after AE + RE but not RE. While training increased ( P < 0.05) in vivo muscle strength in both legs, normalized and concentric torque increased after RE only. Thus AE activates AMPK, reduces glycogen stores, and impairs the progression of concentric force, yet muscle hypertrophic responses to chronic RE training appear not to be compromised.
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Affiliation(s)
- Tommy R. Lundberg
- Department of Health Sciences, Mid Sweden University, Östersund, Sweden
| | - Rodrigo Fernandez-Gonzalo
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and
- Department of Laboratory Medicine, Section for Clinical Physiology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Per A. Tesch
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and
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Moore DR, Camera DM, Areta JL, Hawley JA. Beyond muscle hypertrophy: why dietary protein is important for endurance athletes. Appl Physiol Nutr Metab 2014; 39:987-97. [PMID: 24806440 DOI: 10.1139/apnm-2013-0591] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Recovery from the demands of daily training is an essential element of a scientifically based periodized program whose twin goals are to maximize training adaptation and enhance performance. Prolonged endurance training sessions induce substantial metabolic perturbations in skeletal muscle, including the depletion of endogenous fuels and damage/disruption to muscle and body proteins. Therefore, increasing nutrient availability (i.e., carbohydrate and protein) in the post-training recovery period is important to replenish substrate stores and facilitate repair and remodelling of skeletal muscle. It is well accepted that protein ingestion following resistance-based exercise increases rates of skeletal muscle protein synthesis and potentiates gains in muscle mass and strength. To date, however, little attention has focused on the ability of dietary protein to enhance skeletal muscle remodelling and stimulate adaptations that promote an endurance phenotype. The purpose of this review is to critically discuss the results of recent studies that have examined the role of dietary protein for the endurance athlete. Our primary aim is to consider the results from contemporary investigations that have advanced our knowledge of how the manipulation of dietary protein (i.e., amount, type, and timing of ingestion) can facilitate muscle remodelling by promoting muscle protein synthesis. We focus on the role of protein in facilitating optimal recovery from, and promoting adaptations to strenuous endurance-based training.
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Affiliation(s)
- Daniel R Moore
- a Faculty of Kinesiology and Physical Education, University of Toronto, Toronto ON, M5S 2W6, Canada
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Fernandez-Gonzalo R, Lundberg TR, Tesch PA. Acute molecular responses in untrained and trained muscle subjected to aerobic and resistance exercise training versus resistance training alone. Acta Physiol (Oxf) 2013; 209:283-94. [PMID: 24112827 DOI: 10.1111/apha.12174] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 08/22/2013] [Accepted: 09/23/2013] [Indexed: 12/11/2022]
Abstract
AIM This study assessed and compared acute muscle molecular responses before and after 5-week training, employing either aerobic (AE) and resistance exercise (RE) or RE only. METHODS Ten men performed one-legged RE, while the contralateral limb performed AE followed by RE 6 h later (AE+RE). Before (untrained) and after (trained) the intervention, acute bouts of RE were performed with or without preceding AE. Biopsies were obtained from m. vastus lateralis of each leg pre- and 3 h post-RE to determine mRNA levels of VEGF, PGC-1α, MuRF-1, atrogin-1, myostatin and phosphorylation of mTOR, p70S6K, rpS6 and eEF2. RESULTS PGC-1α and VEGF expression increased (P < 0.05) after acute RE in the untrained, but not the trained state. These markers showed greater response after AE+RE than RE in either condition. Myostatin was lower after AE+RE than RE, both before and after training. AE+RE showed higher MuRF-1 and atrogin-1 expression than RE in the untrained, not the trained state. Exercise increased (P < 0.05) p70S6K phosphorylation both before and after training, yet this increase tended to be more prominent for AE+RE than RE before training. Phosphorylation of p70S6K was greater in trained muscle. Changes in these markers did not correlate with exercise-induced alterations in strength or muscle size. CONCLUSION Concurrent exercise in untrained skeletal muscle prompts global molecular responses consistent with resulting whole muscle adaptations. Yet, training blunts the more robust anabolic response shown after AE+RE compared with RE. This study challenges the concept that single molecular markers could predict training-induced changes in muscle size or strength.
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Affiliation(s)
- R. Fernandez-Gonzalo
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
- Department of Laboratory Medicine; Division of Clinical Physiology; Karolinska Institutet; Karolinska University Hospital; Stockholm Sweden
| | - T. R. Lundberg
- Department of Health Sciences; Mid Sweden University; Östersund Sweden
| | - P. A. Tesch
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm Sweden
- Department of Health Sciences; Mid Sweden University; Östersund Sweden
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Edgett BA, Fortner ML, Bonen A, Gurd BJ. Mammalian target of rapamycin pathway is up-regulated by both acute endurance exercise and chronic muscle contraction in rat skeletal muscle. Appl Physiol Nutr Metab 2013; 38:862-9. [PMID: 23855274 DOI: 10.1139/apnm-2012-0405] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined changes in the expression of translation initiation regulatory proteins and mRNA following both an acute bout of endurance exercise and chronic muscle contractile activity. Female Sprague Dawley rats ran for 2 h at 15 m·min(-1) followed by an increase in speed of 5 m·min(-1) every 5 min until volitional fatigue. The red gastrocnemius muscle was harvested from nonexercised animals (control; n = 6) and from animals that exercised either immediately after exercise (n = 6) or following 3 h of recovery from exercise (n = 6). Compared with control, ribosomal protein S6 (rpS6) mRNA was elevated (p < 0.05) at both 0 h (+32%) and 3 h (+47%). Both a catalytic subunit of eukaryotic initiation factor 2B (eIF2Bε) (+127%) and mammalian target of rapamycin (mTOR) mRNA (+44%) were increased at 3 h, compared with control. Phosphorylation of mTOR (+40%) and S6 kinase 1 (S6K1) (+266%) were increased immediately after exercise (p < 0.05). Female Sprague Dawley rats also underwent chronic stimulation of the peroneal nerve continuously for 7 days. The red gastrocnemius muscle was removed 24 h after cessation of the stimulation. Chronic muscle stimulation increased (p < 0.05) mTOR protein (+74%), rpS6 (+31%), and eukaryotic initiation factor 2α (+44%, p = 0.069), and this was accompanied by an increase in cytochrome c (+31%). Increased resting phosphorylation was observed for rpS6 (+51%) (p < 0.05) but not for mTOR or eukaryotic initiation factor 4E binding protein 1. These experiments demonstrate that both acute and chronic contractile activity up-regulate the mTOR pathway and mitochondrial content in murine skeletal muscle. This up-regulation of the mTOR pathway may increase translation efficiency and may also represent an important control point in exercise-mediated mitochondrial biogenesis.
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Affiliation(s)
- Brittany A Edgett
- a School of Kinesiology and Health Studies, Queen's University, Kingston, ON K7L 3N6, Canada
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The role of mTORC1 in regulating protein synthesis and skeletal muscle mass in response to various mechanical stimuli. Rev Physiol Biochem Pharmacol 2013; 166:43-95. [PMID: 24442322 DOI: 10.1007/112_2013_17] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Skeletal muscle plays a fundamental role in mobility, disease prevention, and quality of life. Skeletal muscle mass is, in part, determined by the rates of protein synthesis, and mechanical loading is a major regulator of protein synthesis and skeletal muscle mass. The mammalian/mechanistic target of rapamycin (mTOR), found in the multi-protein complex, mTORC1, is proposed to play an essential role in the regulation of protein synthesis and skeletal muscle mass. The purpose of this review is to examine the function of mTORC1 in relation to protein synthesis and cell growth, the current evidence from rodent and human studies for the activation of mTORC1 signaling by different types of mechanical stimuli, whether mTORC1 signaling is necessary for changes in protein synthesis and skeletal muscle mass that occur in response to different types of mechanical stimuli, and the proposed molecular signaling mechanisms that may be responsible for the mechanical activation of mTORC1 signaling.
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Carter HN, Hood DA. Contractile activity-induced mitochondrial biogenesis and mTORC1. Am J Physiol Cell Physiol 2012; 303:C540-7. [PMID: 22700793 DOI: 10.1152/ajpcell.00156.2012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In response to exercise training, or chronic contractile activity, mitochondrial content is known to be enriched within skeletal muscle. However, the molecular mechanisms that mediate this adaptation are incompletely defined. Recently, the protein complex, mammalian target of rapamycin complex 1 (mTORC1), has been identified to facilitate the expression of nuclear genes encoding mitochondrial proteins (NUGEMPs) in resting muscle cells via the interaction of the mTORC1 components, mTOR and raptor, the transcription factor Yin Yang 1, and peroxisome proliferator-activated receptor-γ coactivator-1α. It is currently unknown if this mechanism is operative during the increase in mitochondrial content that occurs within skeletal muscle with chronic contractile activity (CCA). Thus we employed a cell culture model of murine skeletal muscle and subjected the myotubes to CCA for 3 h per day for 4 consecutive days in the presence or absence of the mTORC1 inhibitor rapamycin. CCA produced increases in the mitochondrial markers cytochrome oxidase (COX) IV (2.5-fold), Tfam (1.5-fold), and COX activity (1.6-fold). Rapamycin-mediated inhibition of mTORC1 did not suppress these CCA-induced increases in mitochondrial proteins and organelle content. mTORC1 inhibition alone produced a selective upregulation of mitochondrial proteins (COX IV, Tfam), but diminished organelle state 3 respiration. CCA restored this impairment to normal. Our results suggest that mTORC1 activity is not integral for the increase in mitochondrial content elicited by CCA, but is required to maintain mitochondrial function and homeostasis in resting muscle.
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Affiliation(s)
- Heather N. Carter
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - David A. Hood
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
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LUNN WILLIAMR, PASIAKOS STEFANM, COLLETTO MEGANR, KARFONTA KIRSTINE, CARBONE JOHNW, ANDERSON JEFFREYM, RODRIGUEZ NANCYR. Chocolate Milk and Endurance Exercise Recovery. Med Sci Sports Exerc 2012; 44:682-91. [DOI: 10.1249/mss.0b013e3182364162] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Walker DK, Dickinson JM, Timmerman KL, Drummond MJ, Reidy PT, Fry CS, Gundermann DM, Rasmussen BB. Exercise, amino acids, and aging in the control of human muscle protein synthesis. Med Sci Sports Exerc 2012; 43:2249-58. [PMID: 21606874 DOI: 10.1249/mss.0b013e318223b037] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this review, we discuss recent research in the field of human skeletal muscle protein metabolism characterizing the acute regulation of mammalian target of rapamycin complex (mTORC) 1 signaling and muscle protein synthesis (MPS) by exercise, amino acid nutrition, and aging. Resistance exercise performed in the fasted state stimulates mixed MPS within 1 h after exercise, which can remain elevated for 48 h. We demonstrate that the activation of mTORC1 signaling (and subsequently enhanced translation initiation) is required for the contraction-induced increase in MPS. In comparison, low-intensity blood flow restriction (BFR) exercise stimulates MPS and mTORC1 signaling to an extent similar to traditional, high-intensity resistance exercise. We also show that mTORC1 signaling is required for the essential amino acid (EAA)-induced increase in MPS. Ingestion of EAAs (or protein) shortly after resistance exercise enhances MPS and mTORC1 signaling compared with resistance exercise or EAAs alone. In older adults, the ability of the skeletal muscle to respond to anabolic stimuli is impaired. For example, in response to an acute bout of resistance exercise, older adults are less able to activate mTORC1 or increase MPS during the first 24 h of postexercise recovery. However, BFR exercise can overcome this impairment. Aging is not associated with a reduced response to EAAs provided the EAA content is sufficient. Therefore, we propose that exercise combined with EAA should be effective not only in improving muscle repair and growth in response to training in athletes, but that strategies such as EAA combined with resistance exercise (or BFR exercise) may be very useful as a countermeasure for sarcopenia and other clinical conditions associated with muscle wasting.
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Affiliation(s)
- Dillon K Walker
- Department of Nutrition & Metabolism, University of Texas Medical Branch, Galveston, TX 77555-1144, USA
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Hulston CJ, Wolsk E, Grøndahl TS, Yfanti C, VAN Hall G. Protein intake does not increase vastus lateralis muscle protein synthesis during cycling. Med Sci Sports Exerc 2012; 43:1635-42. [PMID: 21364482 DOI: 10.1249/mss.0b013e31821661ab] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study aimed to investigate the effect of protein ingestion on leg protein turnover and vastus lateralis muscle protein synthesis during bicycle exercise and recovery. METHODS Eight healthy males participated in two experiments in which they ingested either a carbohydrate solution (CHO) providing 0.49 g·kg(-1)·h(-1), or a carbohydrate and protein solution (CHO + P) providing 0.49 and 0.16 g·kg(-1)·h(-1), during 3 h of bicycle exercise and 3 h of recovery. Leg protein turnover was determined from stable isotope infusion (l-[ring-C6]phenylalanine), femoral-arterial venous blood sampling, and blood flow measurements. Muscle protein synthesis was calculated from the incorporation of l-[ring-C6]phenylalanine into protein. RESULTS Consuming protein during exercise increased leg protein synthesis and decreased net leg protein breakdown; however, protein ingestion did not increase protein synthesis within the highly active vastus lateralis muscle (0.029%·h(-1), ± 0.004%·h(-1), and 0.030%·h(-1), ± 0.003%·h(-1), in CHO and CHO + P, respectively; P = 0.88). In contrast, consuming protein, during exercise and recovery, increased postexercise vastus lateralis muscle protein synthesis by 51% ± 22% (0.070%·h(-1), ± 0.003%·h(-1), and 0.105%·h(-1), ± 0.013%·h(-1), in CHO and CHO+P, respectively; P < 0.01). Furthermore, leg protein net balance was negative during recovery with CHO intake, whereas positive leg protein net balance was achieved with CHO+P intake. CONCLUSIONS We conclude that consuming protein during prolonged bicycle exercise does not increase protein synthesis within highly active leg muscles. However, protein intake may have stimulated protein synthesis within less active leg muscles and/or other nonmuscle leg tissue. Finally, protein supplementation, during exercise and recovery, enhanced postexercise muscle protein synthesis and resulted in positive leg protein net balance.
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Affiliation(s)
- Carl J Hulston
- Metabolic Mass-Spectrometry Facility, Rigshospitalet, Copenhagen, Denmark.
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Jamart C, Francaux M, Millet GY, Deldicque L, Frère D, Féasson L. Modulation of autophagy and ubiquitin-proteasome pathways during ultra-endurance running. J Appl Physiol (1985) 2012; 112:1529-37. [PMID: 22345427 DOI: 10.1152/japplphysiol.00952.2011] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In this study, the coordinated activation of ubiquitin-proteasome pathway (UPP), autophagy-lysosomal pathway (ALP), and mitochondrial remodeling including mitophagy was assessed by measuring protein markers during ultra-endurance running exercise in human skeletal muscle. Eleven male, experienced ultra-endurance athletes ran for 24 h on a treadmill. Muscle biopsy samples were taken from the vastus lateralis muscle 2 h before starting and immediately after finishing exercise. Athletes ran 149.8 ± 16.3 km with an effective running time of 18 h 42 min ( ± 41 min). The phosphorylation state of Akt (-74 ± 5%; P < 0.001), FOXO3a (-49 ± 9%; P < 0.001), mTOR Ser2448 (-32 ± 14%; P = 0.028), and 4E-BP1 (-34 ± 7%; P < 0.001) was decreased, whereas AMPK phosphorylation state increased by 247 ± 170% (P = 0.042). Proteasome β2 subunit activity increased by 95 ± 44% (P = 0.028), whereas the activities associated with the β1 and β5 subunits remained unchanged. MuRF1 protein level increased by 55 ± 26% (P = 0.034), whereas MAFbx protein and ubiquitin-conjugated protein levels did not change. LC3bII increased by 554 ± 256% (P = 0.005), and the form of ATG12 conjugated to ATG5 increased by 36 ± 17% (P = 0.042). The mitochondrial fission marker phospho-DRP1 increased by 110 ± 47% (P = 0.003), whereas the fusion marker Mfn1 and the mitophagy markers Parkin and PINK1 remained unchanged. These results fit well with a coordinated regulation of ALP and UPP triggered by FOXO3 and AMPK during ultra-endurance exercise.
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Affiliation(s)
- Cécile Jamart
- Institute of Neuroscience, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
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Pesta D, Hoppel F, Macek C, Messner H, Faulhaber M, Kobel C, Parson W, Burtscher M, Schocke M, Gnaiger E. Similar qualitative and quantitative changes of mitochondrial respiration following strength and endurance training in normoxia and hypoxia in sedentary humans. Am J Physiol Regul Integr Comp Physiol 2011; 301:R1078-87. [DOI: 10.1152/ajpregu.00285.2011] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Endurance and strength training are established as distinct exercise modalities, increasing either mitochondrial density or myofibrillar units. Recent research, however, suggests that mitochondrial biogenesis is stimulated by both training modalities. To test the training “specificity” hypothesis, mitochondrial respiration was studied in permeabilized muscle fibers from 25 sedentary adults after endurance (ET) or strength training (ST) in normoxia or hypoxia [fraction of inspired oxygen (FiO2) = 21% or 13.5%]. Biopsies were taken from the musculus vastus lateralis, and cycle-ergometric incremental maximum oxygen uptake (V̇o2max) exercise tests were performed under normoxia, before and after the 10-wk training program. The main finding was a significant increase ( P < 0.05) of fatty acid oxidation capacity per muscle mass, after endurance and strength training under normoxia [2.6- and 2.4-fold for endurance training normoxia group (ETN) and strength training normoxia group (STN); n = 8 and 3] and hypoxia [2.0-fold for the endurance training hypoxia group (ETH) and strength training hypoxia group (STH); n = 7 and 7], and higher coupling control of oxidative phosphorylation. The enhanced lipid oxidative phosphorylation (OXPHOS) capacity was mainly (87%) due to qualitative mitochondrial changes increasing the relative capacity for fatty acid oxidation ( P < 0.01). Mitochondrial tissue-density contributed to a smaller extent (13%), reflected by the gain in muscle mass-specific respiratory capacity with a physiological substrate cocktail (glutamate, malate, succinate, and octanoylcarnitine). No significant increase was observed in mitochondrial DNA (mtDNA) content. Physiological OXPHOS capacity increased significantly in ETN ( P < 0.01), with the same trend in ETH and STH ( P < 0.1). The limitation of flux by the phosphorylation system was diminished after training. Importantly, key mitochondrial adaptations were similar after endurance and strength training, regardless of normoxic or hypoxic exercise. The transition from a sedentary to an active lifestyle induced muscular changes of mitochondrial quality representative of mitochondrial health.
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Affiliation(s)
- Dominik Pesta
- Division of Diagnostic Radiology I, Department of Radiology, Innsbruck Medical University, Innsbruck, Austria
- D. Swarovski Research Laboratory, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck Medical University, Innsbruck, Austria
| | - Florian Hoppel
- Department of Sport Science, Medical Section, University of Innsbruck, Innsbruck, Austria
| | - Christian Macek
- Department of Sport Science, Medical Section, University of Innsbruck, Innsbruck, Austria
| | - Hubert Messner
- Division of Diagnostic Radiology I, Department of Radiology, Innsbruck Medical University, Innsbruck, Austria
| | - Martin Faulhaber
- Department of Sport Science, Medical Section, University of Innsbruck, Innsbruck, Austria
| | - Conrad Kobel
- Department of Medical Statistics, Informatics and Health Economics, Innsbruck Medical University, Innsbruck, Austria; and
| | - Walther Parson
- Institute of Legal Medicine, Innsbruck Medical University, Innsbruck, Austria
| | - Martin Burtscher
- Department of Sport Science, Medical Section, University of Innsbruck, Innsbruck, Austria
| | - Michael Schocke
- Division of Diagnostic Radiology I, Department of Radiology, Innsbruck Medical University, Innsbruck, Austria
| | - Erich Gnaiger
- D. Swarovski Research Laboratory, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck Medical University, Innsbruck, Austria
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Pasiakos SM, McClung HL, McClung JP, Margolis LM, Andersen NE, Cloutier GJ, Pikosky MA, Rood JC, Fielding RA, Young AJ. Leucine-enriched essential amino acid supplementation during moderate steady state exercise enhances postexercise muscle protein synthesis. Am J Clin Nutr 2011; 94:809-18. [PMID: 21775557 DOI: 10.3945/ajcn.111.017061] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The effects of essential amino acid (EAA) supplementation during moderate steady state (ie, endurance) exercise on postexercise skeletal muscle metabolism are not well described, and the potential role of supplemental leucine on muscle protein synthesis (MPS) and associated molecular responses remains to be elucidated. OBJECTIVE This randomized crossover study examined whether EAA supplementation with 2 different concentrations of leucine affected post-steady state exercise MPS, whole-body protein turnover, and mammalian target of rapamycin 1 (mTORC1) intracellular signaling. DESIGN Eight adults completed 2 separate bouts of cycle ergometry [60 min, 60% VO(2)peak (peak oxygen uptake)]. Isonitrogenous (10 g EAA) drinks with different leucine contents [leucine-enriched (l)-EAA, 3.5 g leucine; EAA, 1.87 g leucine] were consumed during exercise. MPS and whole-body protein turnover were determined by using primed continuous infusions of [(2)H(5)]phenylalanine and [1-(13)C]leucine. Multiplex and immunoblot analyses were used to quantify mTORC1 signaling. RESULTS MPS was 33% greater (P < 0.05) after consumption of L-EAA (0.08 ± 0.01%/h) than after consumption of EAA (0.06 ± 0.01%/h). Whole-body protein breakdown and synthesis were lower (P < 0.05) and oxidation was greater (P < 0.05) after consumption of L-EAA than after consumption of EAA. Regardless of dietary treatment, multiplex analysis indicated that Akt and mammalian target of rapamycin phosphorylation were increased (P < 0.05) 30 min after exercise. Immunoblot analysis indicated that phosphorylation of ribosomal protein S6 and extracellular-signal regulated protein kinase increased (P < 0.05) and phosphorylation of eukaryotic elongation factor 2 decreased (P < 0.05) after exercise but was not affected by dietary treatment. CONCLUSION These findings suggest that increasing the concentration of leucine in an EAA supplement consumed during steady state exercise elicits a greater MPS response during recovery. This trial is registered at clinicaltrials.gov as NCT01366924.
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Affiliation(s)
- Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA.
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Breen L, Philp A, Witard OC, Jackman SR, Selby A, Smith K, Baar K, Tipton KD. The influence of carbohydrate-protein co-ingestion following endurance exercise on myofibrillar and mitochondrial protein synthesis. J Physiol 2011; 589:4011-25. [PMID: 21746787 DOI: 10.1113/jphysiol.2011.211888] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The aim of the present study was to determine mitochondrial and myofibrillar muscle protein synthesis (MPS) when carbohydrate (CHO) or carbohydrate plus protein (C+P) beverages were ingested following prolonged cycling exercise. The intracellular mechanisms thought to regulate MPS were also investigated. In a single-blind, cross-over study, 10 trained cyclists (age 29 ± 6 years, VO2max 66.5 ± 5.1 ml kg(−1) min(−1)) completed two trials in a randomized order. Subjects cycled for 90 min at 77 ± 1% VO2max before ingesting a CHO (25 g of carbohydrate) or C+P (25 g carbohydrate + 10 g whey protein) beverage immediately and 30 min post-exercise. A primed constant infusion of L-[ring-(13)C6]phenylalanine began 1.5 h prior to exercise and continued until 4 h post-exercise. Muscle biopsy samples were obtained to determine myofibrillar and mitochondrial MPS and the phosphorylation of intracellular signalling proteins. Arterialized blood samples were obtained throughout the protocol. Plasma amino acid and urea concentrations increased following ingestion of C+P only. Serum insulin concentration increased more for C+P than CHO. Myofibrillar MPS was ∼35% greater for C+P compared with CHO (0.087 ± 0.007 and 0.057 ± 0.006% h(−1), respectively; P = 0.025). Mitochondrial MPS rates were similar for C+P and CHO (0.082 ± 0.011 and 0.086 ± 0.018% h(−1), respectively). mTOR(Ser2448) phosphorylation was greater for C+P compared with CHO at 4 h post-exercise (P < 0.05). p70S6K(Thr389) phosphorylation increased at 4 h post-exercise for C+P (P < 0.05), whilst eEF2(Thr56) phosphorylation increased by ∼40% at 4 h post-exercise for CHO only (P < 0.01). The present study demonstrates that the ingestion of protein in addition to carbohydrate stimulates an increase in myofibrillar, but not mitochondrial, MPS following prolonged cycling. These data indicate that the increase in myofibrillar MPS for C+P could, potentially, be mediated through p70S6K, downstream of mTOR, which in turn may suppress the rise in eEF2 on translation elongation.
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Affiliation(s)
- Leigh Breen
- School of Sport and Exercise Sciences, University of Birmingham, Birmingham, UK.
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Mascher H, Ekblom B, Rooyackers O, Blomstrand E. Enhanced rates of muscle protein synthesis and elevated mTOR signalling following endurance exercise in human subjects. Acta Physiol (Oxf) 2011; 202:175-84. [PMID: 21385328 DOI: 10.1111/j.1748-1716.2011.02274.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
AIM The major aim of this study was to determine the fractional rate of protein synthesis (FSR) during the early period of recovery after intensive aerobic exercise in the absence of nutritional supplementation. METHODS Sixteen male subjects performed one-legged cycling exercise for 1 h at approx. 65-70% of their one-legged maximal oxygen uptake. Using the stable isotope technique, the FSR in the vastus lateralis of both legs were determined during two periods, 0-90 min (n = 8) and 90-180 min (n = 8) after exercise. Biopsies were taken from both exercising and resting muscle before exercise, immediately after and following 90 or 180 min of recovery. RESULTS During the initial 90 min of recovery, FSR in the exercising muscle tended to be higher than in the resting muscle (1.57 ± 0.12 vs. 1.44 ± 0.07% 24 h(-1); P = 0.1) and was significantly higher during the period 90-180 min after exercise (1.74 ± 0.14 vs. 1.43 ± 0.12% 24 h(-1) ; P < 0.05). Exercise induced a 60% increase (P < 0.05) in phosphorylation of mTOR and a fivefold increase (P < 0.05) in Thr(389) phosphorylation of p70S6 kinase as well as a 30% reduction (P < 0.05) in phosphorylation of eEF2. Phosphorylation of AMP-activated protein kinase was enhanced by 40% (P < 0.05) after exercise, but no significant effect on phosphorylation of Akt, or eIF2Bε was observed immediately after exercise. CONCLUSION These findings indicate that during the first 3 h of recovery after intensive endurance exercise FSR gradually increases. Moreover, a stimulation of the mTOR-signalling pathway may be at least partially responsible for this elevated protein synthesis.
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Affiliation(s)
- H Mascher
- The Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
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Ludlow AT, Roth SM. Physical activity and telomere biology: exploring the link with aging-related disease prevention. J Aging Res 2011; 2011:790378. [PMID: 21403893 PMCID: PMC3043290 DOI: 10.4061/2011/790378] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Revised: 12/18/2010] [Accepted: 12/30/2010] [Indexed: 11/20/2022] Open
Abstract
Physical activity is associated with reduced risk of several age-related diseases as well as with increased longevity in both rodents and humans. Though these associations are well established, evidence of the molecular and cellular factors associated with reduced disease risk and increased longevity resulting from physical activity is sparse. A long-standing hypothesis of aging is the telomere hypothesis: as a cell divides, telomeres shorten resulting eventually in replicative senescence and an aged phenotype. Several reports have recently associated telomeres and telomere-related proteins to diseases associated with physical inactivity and aging including cardiovascular disease, insulin resistance, and hypertension. Interestingly several reports have also shown that longer telomeres are associated with higher physical activity levels, indicating a potential mechanistic link between physical activity, reduced age-related disease risk, and longevity. The primary purpose of this review is to discuss the potential importance of physical activity in telomere biology in the context of inactivity- and age-related diseases. A secondary purpose is to explore potential mechanisms and important avenues for future research in the field of telomeres and diseases associated with physical inactivity and aging.
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Affiliation(s)
- Andrew T Ludlow
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD 20742-2611, USA
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Camera DM, Edge J, Short MJ, Hawley JA, Coffey VG. Early time course of Akt phosphorylation after endurance and resistance exercise. Med Sci Sports Exerc 2011; 42:1843-52. [PMID: 20195183 DOI: 10.1249/mss.0b013e3181d964e4] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The aim of this study was to determine the early time course of exercise-induced signaling after divergent contractile activity associated with resistance and endurance exercise. METHODS Sixteen male subjects were randomly assigned to either a cycling (CYC; n = 8, 60 min, 70% V˙O2peak) or resistance (REX; n = 8, 8 x 5 leg extension, 80% one-repetition maximum, 3-min recovery) exercise group. Serial muscle biopsies were obtained from vastus lateralis at rest before, immediately after, and after 15, 30, and 60 min of passive recovery to determine early signaling responses after exercise. RESULTS There were comparable increases from rest in Akt(Thr308/Ser473) and mTOR(Ser2448) phosphorylation during the postexercise time course that peaked 30-60 min after both CYC and REX (P < 0.05). There were also similar patterns in p70S6K(Thr389) and 4E-BP1(Thr37/46) phosphorylation, but a greater magnitude of effect was observed for REX and CYC, respectively (P < 0.05). However, AMPK(Thr172) phosphorylation was only significantly elevated after CYC (P < 0.05), and we observed divergent responses for glycogen synthase(Ser641) and AS160 phosphorylation that were enhanced after CYC but not REX (P < 0.05). CONCLUSIONS We show a similar time course for Akt-mTOR-S6K phosphorylation during the initial 60-min recovery period after divergent contractile stimuli. Conversely, enhanced phosphorylation status of proteins that promote glucose transport and glycogen synthesis only occurred after endurance exercise. Our results indicate that endurance and resistance exercise initiate translational signaling, but high-load, low-repetition contractile activity failed to promote phosphorylation of pathways regulating glucose metabolism.
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Affiliation(s)
- Donny M Camera
- School of Medical Science, Health Innovations Research Institute, RMIT University, Melbourne, Australia
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Argadine HM, Mantilla CB, Zhan WZ, Sieck GC. Intracellular signaling pathways regulating net protein balance following diaphragm muscle denervation. Am J Physiol Cell Physiol 2010; 300:C318-27. [PMID: 21084642 DOI: 10.1152/ajpcell.00172.2010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Unilateral denervation (DNV) of rat diaphragm muscle increases protein synthesis at 3 days after DNV (DNV-3D) and degradation at DNV-5D, such that net protein breakdown is evident by DNV-5D. On the basis of existing models of protein balance, we examined DNV-induced changes in Akt, AMP-activated protein kinase (AMPK), and ERK½ activation, which can lead to increased protein synthesis via mammalian target of rapamycin (mTOR)/p70S6 kinase (p70S6K), glycogen synthase kinase-3β (GSK3β), or eukaryotic initiation factor 4E (eIF4E), and increased protein degradation via forkhead box protein O (FoxO). Protein phosphorylation was measured using Western analyses through DNV-5D. Akt phosphorylation decreased at 1 h and 6 h after DNV compared with sham despite decreased AMPK phosphorylation. Both Akt and AMPK phosphorylation returned to sham levels by DNV-1D. Phosphorylation of their downstream effector mTOR (Ser2481) did not change at any time point after DNV, and phosphorylated p70S6K and eIF4E-binding protein 1 (4EBP1) increased only by DNV-5D. In contrast, ERK½ phosphorylation and its downstream effector eIF4E increased 1.7-fold at DNV-1D and phosphorylated GSK3β increased 1.5-fold at DNV-3D (P < 0.05 for both comparisons). Thus, following DNV there are differential effects on protein synthetic pathways with preferential activation of GSK3β and eIF4E over p70S6K. FoxO1 nuclear translocation occurred by DNV-1D, consistent with its role in increasing expression of atrogenes necessary for subsequent ubiquitin-proteasome activation evident by DNV-5D. On the basis of our results, increased protein synthesis following DNV is associated with changes in ERK½-dependent pathways, but protein degradation results from downregulation of Akt and nuclear translocation of FoxO1. No single trigger is responsible for protein balance following DNV. Protein balance in skeletal muscle depends on multiple synthetic/degradation pathways that should be studied in concert.
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