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Fowler A, Knaus KR, Khuu S, Khalilimeybodi A, Schenk S, Ward SR, Fry AC, Rangamani P, McCulloch AD. Network model of skeletal muscle cell signalling predicts differential responses to endurance and resistance exercise training. Exp Physiol 2024; 109:939-955. [PMID: 38643471 PMCID: PMC11140181 DOI: 10.1113/ep091712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 03/20/2024] [Indexed: 04/22/2024]
Abstract
Exercise-induced muscle adaptations vary based on exercise modality and intensity. We constructed a signalling network model from 87 published studies of human or rodent skeletal muscle cell responses to endurance or resistance exercise in vivo or simulated exercise in vitro. The network comprises 259 signalling interactions between 120 nodes, representing eight membrane receptors and eight canonical signalling pathways regulating 14 transcriptional regulators, 28 target genes and 12 exercise-induced phenotypes. Using this network, we formulated a logic-based ordinary differential equation model predicting time-dependent molecular and phenotypic alterations following acute endurance and resistance exercises. Compared with nine independent studies, the model accurately predicted 18/21 (85%) acute responses to resistance exercise and 12/16 (75%) acute responses to endurance exercise. Detailed sensitivity analysis of differential phenotypic responses to resistance and endurance training showed that, in the model, exercise regulates cell growth and protein synthesis primarily by signalling via mechanistic target of rapamycin, which is activated by Akt and inhibited in endurance exercise by AMP-activated protein kinase. Endurance exercise preferentially activates inflammation via reactive oxygen species and nuclear factor κB signalling. Furthermore, the expected preferential activation of mitochondrial biogenesis by endurance exercise was counterbalanced in the model by protein kinase C in response to resistance training. This model provides a new tool for investigating cross-talk between skeletal muscle signalling pathways activated by endurance and resistance exercise, and the mechanisms of interactions such as the interference effects of endurance training on resistance exercise outcomes.
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Affiliation(s)
- Annabelle Fowler
- Department of BioengineeringUniversity of California SanDiegoLa JollaCaliforniaUSA
| | - Katherine R. Knaus
- Department of BioengineeringUniversity of California SanDiegoLa JollaCaliforniaUSA
| | - Stephanie Khuu
- Department of BioengineeringUniversity of California SanDiegoLa JollaCaliforniaUSA
| | - Ali Khalilimeybodi
- Department of Mechanical and Aerospace EngineeringUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Simon Schenk
- Department of Orthopaedic SurgeryUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Samuel R. Ward
- Department of Orthopaedic SurgeryUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Andrew C. Fry
- Department of Health, Sport and Exercise SciencesUniversity of KansasLawrenceKansasUSA
| | - Padmini Rangamani
- Department of Mechanical and Aerospace EngineeringUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Andrew D. McCulloch
- Department of BioengineeringUniversity of California SanDiegoLa JollaCaliforniaUSA
- Department of MedicineUniversity of California San DiegoLa JollaCaliforniaUSA
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Roberts MD, McCarthy JJ, Hornberger TA, Phillips SM, Mackey AL, Nader GA, Boppart MD, Kavazis AN, Reidy PT, Ogasawara R, Libardi CA, Ugrinowitsch C, Booth FW, Esser KA. Mechanisms of mechanical overload-induced skeletal muscle hypertrophy: current understanding and future directions. Physiol Rev 2023; 103:2679-2757. [PMID: 37382939 PMCID: PMC10625844 DOI: 10.1152/physrev.00039.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 06/12/2023] [Accepted: 06/21/2023] [Indexed: 06/30/2023] Open
Abstract
Mechanisms underlying mechanical overload-induced skeletal muscle hypertrophy have been extensively researched since the landmark report by Morpurgo (1897) of "work-induced hypertrophy" in dogs that were treadmill trained. Much of the preclinical rodent and human resistance training research to date supports that involved mechanisms include enhanced mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling, an expansion in translational capacity through ribosome biogenesis, increased satellite cell abundance and myonuclear accretion, and postexercise elevations in muscle protein synthesis rates. However, several lines of past and emerging evidence suggest that additional mechanisms that feed into or are independent of these processes are also involved. This review first provides a historical account of how mechanistic research into skeletal muscle hypertrophy has progressed. A comprehensive list of mechanisms associated with skeletal muscle hypertrophy is then outlined, and areas of disagreement involving these mechanisms are presented. Finally, future research directions involving many of the discussed mechanisms are proposed.
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Affiliation(s)
- Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
| | - Troy A Hornberger
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Stuart M Phillips
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gustavo A Nader
- Department of Kinesiology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States
| | - Marni D Boppart
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States
| | - Andreas N Kavazis
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Paul T Reidy
- Department of Kinesiology, Nutrition and Health, Miami University, Oxford, Ohio, United States
| | - Riki Ogasawara
- Healthy Food Science Research Group, Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Cleiton A Libardi
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
| | - Carlos Ugrinowitsch
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri, United States
| | - Karyn A Esser
- Department of Physiology and Aging, College of Medicine, University of Florida, Gainesville, Florida, United States
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Bersiner K, Park SY, Schaaf K, Yang WH, Theis C, Jacko D, Gehlert S. Resistance exercise: a mighty tool that adapts, destroys, rebuilds and modulates the molecular and structural environment of skeletal muscle. Phys Act Nutr 2023; 27:78-95. [PMID: 37583075 PMCID: PMC10440184 DOI: 10.20463/pan.2023.0021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 08/17/2023] Open
Abstract
PURPOSE Skeletal muscle regulates health and performance by maintaining or increasing strength and muscle mass. Although the molecular mechanisms in response to resistance exercise (RE) significantly target the activation of protein synthesis, a plethora of other mechanisms and structures must be involved in orchestrating the communication, repair, and restoration of homeostasis after RE stimulation. In practice, RE can be modulated by variations in intensity, continuity and volume, which affect molecular responses and skeletal muscle adaptation. Knowledge of these aspects is important with respect to planning of training programs and assessing the impact of RE training on skeletal muscle. METHODS In this narrative review, we introduce general aspects of skeletal muscle substructures that adapt in response to RE. We further highlighted the molecular mechanisms that control human skeletal muscle anabolism, degradation, repair and memory in response to acute and repeated RE and linked these aspects to major training variables. RESULTS Although RE is a key stimulus for the activation of skeletal muscle anabolism, it also induces myofibrillar damage. Nevertheless, to increase muscle mass accompanied by a corresponding adaptation of the essential substructures of the sarcomeric environment, RE must be continuously repeated. This requires the permanent engagement of molecular mechanisms that re-establish skeletal muscle integrity after each RE-induced muscle damage. CONCLUSION Various molecular regulators coordinately control the adaptation of skeletal muscle after acute and repeated RE and expand their actions far beyond muscle growth. Variations of key resistance training variables likely affect these mechanisms without affecting muscle growth.
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Affiliation(s)
- Käthe Bersiner
- Department for Biosciences of Sports, Institute of Sports Science, University of Hildesheim, Hildesheim, Germany
| | - So-Young Park
- Graduate School of Sports Medicine, CHA University, Pocheon, Republic of Korea
| | - Kirill Schaaf
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Woo-Hwi Yang
- Graduate School of Sports Medicine, CHA University, Pocheon, Republic of Korea
- Department of Medicine, General Graduate School, CHA University, Pocheon, Republic of Korea
| | - Christian Theis
- Center for Anaesthesiology, Helios University Hospital Wuppertal, Wuppertal, Germany
| | - Daniel Jacko
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Sebastian Gehlert
- Department for Biosciences of Sports, Institute of Sports Science, University of Hildesheim, Hildesheim, Germany
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Influence of mTOR-regulated anabolic pathways on equine skeletal muscle health. J Equine Vet Sci 2023; 124:104281. [PMID: 36905972 DOI: 10.1016/j.jevs.2023.104281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/11/2023]
Abstract
Skeletal muscle is a highly dynamic organ that is essential for locomotion as well as endocrine regulation in all populations of horses. However, despite the importance of adequate muscle development and maintenance, the mechanisms underlying protein anabolism in horses on different diets, exercise programs, and at different life stages remain obscure. Mechanistic target of rapamycin (mTOR) is a key component of the protein synthesis pathway and is regulated by biological factors such as insulin and amino acid availability. Providing a diet ample in vital amino acids, such as leucine and glutamine, is essential in activating sensory pathways that recruit mTOR to the lysosome and assist in the translation of important downstream targets. When the diet is well balanced, mitochondrial biogenesis and protein synthesis are activated in response to increased exercise bouts in the performing athlete. It is important to note that the mTOR kinase pathways are multi-faceted and very complex, with several binding partners and targets that lead to specific functions in protein turnover of the cell, and ultimately, the capacity to maintain or grow muscle mass. Further, these pathways are likely altered across the lifespan, with an emphasis of growth in young horses while decreases in musculature with aged horses appears to be attributable to degradation or other regulators of protein synthesis rather than alterations in the mTOR pathway. Previous work has begun to pinpoint ways in which the mTOR pathway is influenced by diet, exercise, and age; however, future research is warranted to quantify the functional outcomes related to changes in mTOR. Promisingly, this could provide direction on appropriate management techniques to support skeletal muscle growth and maximize athletic potential in differing equine populations.
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Viggars MR, Sutherland H, Lanmüller H, Schmoll M, Bijak M, Jarvis JC. Adaptation of the transcriptional response to resistance exercise over 4 weeks of daily training. FASEB J 2023; 37:e22686. [PMID: 36468768 DOI: 10.1096/fj.202201418r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/05/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022]
Abstract
We present the time course of change in the muscle transcriptome 1 h after the last exercise bout of a daily resistance training program lasting 2, 10, 20, or 30 days. Daily exercise in rat tibialis anterior muscles (5 sets of 10 repetitions over 20 min) induced progressive muscle growth that approached a new stable state after 30 days. The acute transcriptional response changed along with progressive adaptation of the muscle phenotype. For example, expression of type 2B myosin was silenced. Time courses recently synthesized from human exercise studies do not demonstrate so clearly the interplay between the acute exercise response and the longer-term consequences of repeated exercise. We highlight classes of transcripts and transcription factors whose expression increases during the growth phase and declines again as the muscle adapts to a new daily pattern of activity and reduces its rate of growth. Myc appears to play a central role.
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Affiliation(s)
- Mark R Viggars
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Department of Physiology and Aging, University of Florida, Gainesville, Florida, USA.,Myology Institute, University of Florida, Gainesville, Florida, USA
| | - Hazel Sutherland
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Hermann Lanmüller
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Martin Schmoll
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Manfred Bijak
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Jonathan C Jarvis
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
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Moustogiannis A, Philippou A, Zevolis E, Taso OS, Giannopoulos A, Chatzigeorgiou A, Koutsilieris M. Effect of Mechanical Loading of Senescent Myoblasts on Their Myogenic Lineage Progression and Survival. Cells 2022; 11:cells11243979. [PMID: 36552743 PMCID: PMC9776690 DOI: 10.3390/cells11243979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/30/2022] [Accepted: 12/03/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND During aging, muscle cell apoptosis increases and myogenesis gradually declines. The impaired myogenic and survival potential of the aged skeletal muscle can be ameliorated by its mechanical loading. However, the molecular responses of aged muscle cells to mechanical loading remain unclear. This study examined the effect of mechanical loading of aged, proliferating, and differentiated myoblasts on the gene expression and signaling responses associated with their myogenic lineage progression and survival. METHODS Control and aged C2C12 cells were cultured on elastic membranes and underwent passive stretching for 12 h at a low frequency (0.25 Hz) and different elongations, varying the strain on days 0 and 10 of myoblast differentiation. Activation of ERK1/2 and Akt, and the expression of focal adhesion kinase (FAK) and key myogenic regulatory factors (MRFs), MyoD and Myogenin, were determined by immunoblotting of the cell lysates derived from stretched and non-stretched myoblasts. Changes in the expression levels of the MRFs, muscle growth, atrophy, and pro-apoptotic factors in response to mechanical loading of the aged and control cells were quantified by real-time qRT-PCR. RESULTS Mechanical stretching applied on myoblasts resulted in the upregulation of FAK both in proliferating (day 0) and differentiated (day 10) cells, as well as in increased phosphorylation of ERK1/2 in both control and aged cells. Moreover, Akt activation and the expression of early differentiation factor MyoD increased significantly after stretching only in the control myoblasts, while the late differentiation factor Myogenin was upregulated in both the control and aged myoblasts. At the transcriptional level, mechanical loading of the proliferating myoblasts led to an increased expression of IGF-1 isoforms and MRFs, and to downregulation of muscle atrophy factors mainly in control cells, as well as in the upregulation of pro-apoptotic factors both in control and aged cells. In differentiated cells, mechanical loading resulted in an increased expression of the IGF-1Ea isoform and Myogenin, and in the downregulation of atrophy and pro-apoptotic factors in both the control and aged cells. CONCLUSIONS This study revealed a diminished beneficial effect of mechanical loading on the myogenic and survival ability of the senescent muscle cells compared with the controls, with a low strain (2%) loading being most effective in upregulating myogenic/anabolic factors and downregulating atrophy and pro-apoptotic genes mainly in the aged myotubes.
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Affiliation(s)
- Athanasios Moustogiannis
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Micras Asias, 115 27 Athens, Greece
| | - Anastassios Philippou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Micras Asias, 115 27 Athens, Greece
| | - Evangelos Zevolis
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Micras Asias, 115 27 Athens, Greece
| | - Orjona S. Taso
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Micras Asias, 115 27 Athens, Greece
- School of Biological Sciences, Deanery of Biomedical Sciences, Centre for Discovery Brain Sciences, Edinburgh EH8 9JZ, UK
| | - Antonios Giannopoulos
- Department of Surgical and Perioperative Sciences, Faculty of Medicine, Umeå University, 901 87 Umeå, Sweden
| | - Antonios Chatzigeorgiou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Micras Asias, 115 27 Athens, Greece
| | - Michael Koutsilieris
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Micras Asias, 115 27 Athens, Greece
- Correspondence: ; Tel.: +30-210-7462690; Fax: +30-210-7462571
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Sherafati-Moghadam M, Pahlavani HA, Daryanoosh F, Salesi M. The effect of high-intensity interval training (HIIT) on protein expression in Flexor Hallucis Longus (FHL) and soleus (SOL) in rats with type 2 diabetes. J Diabetes Metab Disord 2022. [PMID: 36404870 PMCID: PMC9672293 DOI: 10.1007/s40200-022-01091-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Purpose In people with diabetes, one of the problems for patients is muscle wasting and inhibition of the protein synthesis pathway. This study aimed to evaluate the effects of HIIT on protein expression in two skeletal muscles, flexor hallucis longus (FHL) and soleus (SOL) in rats with type 2 diabetes mellitus (T2DM). Materials and methods Diabetes initially was induced by streptozotocin (STZ) and nicotinamide. Rats with type 2 diabetes were randomly and equally divided into control (n = 6) and HIIT groups (n = 6). After 8 weeks of training, the content of total and phosphorylated proteins of serine/threonine-protein kinases (AKT1), mammalian target of rapamycin (mTOR), P70 ribosomal protein S6 kinase 1 (P70S6K1), and 4E (eIF4E)-binding protein 1 (4E-BP1) in FHL and SOL muscles were measured by Western blotting. While body weight and blood glucose were also controlled. Results In the HIIT training group, compared to the control group, a significant increase in the content of AKT1 (0.003) and mTOR (0.001) proteins was observed in the FHL muscle. Also, after 8 weeks of HIIT training, protein 4E-BP1 (0.001) was increased in SOL muscle. However, there was no significant change in other proteins in FHL and SOL muscle. Conclusions In rats with type 2 diabetes appear to HIIT leading to more protein expression of fast-twitch muscles than slow-twitch muscles. thus likely HIIT exercises can be an important approach to increase protein synthesis and prevent muscle atrophy in people with type 2 diabetes.
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Jacko D, Schaaf K, Masur L, Windoffer H, Aussieker T, Schiffer T, Zacher J, Bloch W, Gehlert S. Repeated and Interrupted Resistance Exercise Induces the Desensitization and Re-Sensitization of mTOR-Related Signaling in Human Skeletal Muscle Fibers. Int J Mol Sci 2022; 23:ijms23105431. [PMID: 35628242 PMCID: PMC9141560 DOI: 10.3390/ijms23105431] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 02/06/2023] Open
Abstract
The acute resistance exercise (RE)-induced phosphorylation of mTOR-related signaling proteins in skeletal muscle can be blunted after repeated RE. The time frame in which the phosphorylation (p) of mTORS2448, p70S6kT421/S424, and rpS6S235/236 will be reduced during an RE training period in humans and whether progressive (PR) loading can counteract such a decline has not been described. (1) To enclose the time frame in which pmTORS2448, prpS6S235/236, and pp70S6kT421/S424 are acutely reduced after RE occurs during repeated RE. (2) To test whether PR will prevent that reduction compared to constant loading (CO) and (3) whether 10 days without RE may re-increase blunted signaling. Fourteen healthy males (24 ± 2.8 yrs.; 1.83 ± 0.1 cm; 79.3 ± 8.5 kg) were subjected to RE with either PR (n = 8) or CO (n = 6) loading. Subjects performed RE thrice per week, conducting three sets with 10−12 repetitions on a leg press and leg extension machine. Muscle biopsies were collected at rest (T0), 45 min after the first (T1), seventh (T7), 13th (T13), and 14th (X-T14) RE session. No differences were found between PR and CO for any parameter. Thus, the groups were combined, and the results show the merged values. prpS6S235/236 and pp70s6kT421/S424 were increased at T1, but were already reduced at T7 and up to T13 compared to T1. Ten days without RE re-increased prpS6S235/236 and pp70S6kT421/S424 at X-T14 to a level comparable to that of T1. pmTORS2448 was increased from T1 to X-T14 and did not decline over the training period. Single-fiber immunohistochemistry revealed a reduction in prpS6S235/236 in type I fibers from T1 to T13 and a re-increase at X-T14, which was more augmented in type II fibers at T13 (p < 0.05). The entity of myofibers revealed a high heterogeneity in the level of prpS6S235/236, possibly reflecting individual contraction-induced stress during RE. The type I and II myofiber diameter increased from T0 and T1 to T13 and X-T14 (p < 0.05) prpS6S235/236 and pp70s6kT421/S424 reflect RE-induced states of desensitization and re-sensitization in dependency on frequent loading by RE, but also by its cessation.
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Affiliation(s)
- Daniel Jacko
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
- Olympic Base Center NRW/Rhineland, 50933 Cologne, Germany
| | - Kirill Schaaf
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
| | - Lukas Masur
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
| | - Hannes Windoffer
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
| | - Thorben Aussieker
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
| | - Thorsten Schiffer
- Outpatient Clinic for Sports Traumatology and Public Health Consultation, German Sport University Cologne, 50933 Cologne, Germany;
| | - Jonas Zacher
- Department ofPreventative and Rehabilitative Sports and Performance Medicine, Institute of Cardiology and Sports Medicine, German Sports University Cologne, 50933 Cologne, Germany;
| | - Wilhelm Bloch
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
- German Research Centre of Elite Sport (Momentum), German Sport University Cologne, 50933 Cologne, Germany
| | - Sebastian Gehlert
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, 50933 Cologne, Germany; (D.J.); (K.S.); (L.M.); (H.W.); (T.A.); (W.B.)
- Institute of Sport Science, Biosciences of Sports, University of Hildesheim, 31141 Hildesheim, Germany
- Correspondence: ; Tel.: +49-(0)-5121-883-580; Fax: +49-(0)-5121-883-591
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Attwaters M, Hughes SM. Cellular and molecular pathways controlling muscle size in response to exercise. FEBS J 2022; 289:1428-1456. [PMID: 33755332 DOI: 10.1111/febs.15820] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/27/2021] [Accepted: 03/12/2021] [Indexed: 12/14/2022]
Abstract
From the discovery of ATP and motor proteins to synaptic neurotransmitters and growth factor control of cell differentiation, skeletal muscle has provided an extreme model system in which to understand aspects of tissue function. Muscle is one of the few tissues that can undergo both increase and decrease in size during everyday life. Muscle size depends on its contractile activity, but the precise cellular and molecular pathway(s) by which the activity stimulus influences muscle size and strength remain unclear. Four correlates of muscle contraction could, in theory, regulate muscle growth: nerve-derived signals, cytoplasmic calcium dynamics, the rate of ATP consumption and physical force. Here, we summarise the evidence for and against each stimulus and what is known or remains unclear concerning their molecular signal transduction pathways and cellular effects. Skeletal muscle can grow in three ways, by generation of new syncytial fibres, addition of nuclei from muscle stem cells to existing fibres or increase in cytoplasmic volume/nucleus. Evidence suggests the latter two processes contribute to exercise-induced growth. Fibre growth requires increase in sarcolemmal surface area and cytoplasmic volume at different rates. It has long been known that high-force exercise is a particularly effective growth stimulus, but how this stimulus is sensed and drives coordinated growth that is appropriately scaled across organelles remains a mystery.
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Affiliation(s)
- Michael Attwaters
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, UK
| | - Simon M Hughes
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, UK
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10
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Petrosino JM, Longenecker JZ, Angell CD, Hinger SA, Martens CR, Accornero F. CCN2 participates in overload-induced skeletal muscle hypertrophy. Matrix Biol 2022; 106:1-11. [PMID: 35045313 PMCID: PMC8854352 DOI: 10.1016/j.matbio.2022.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 01/02/2022] [Accepted: 01/10/2022] [Indexed: 02/03/2023]
Abstract
The regulation of skeletal muscle growth following pro-hypertrophic stimuli requires a coordinated response by different cell types that leads to extracellular matrix (ECM) remodeling and increases in muscle cross-sectional area. Indeed, matricellular proteins serve a key role as communication vehicles that facilitate the propagation of signaling stimuli required for muscle adaptation to environmental challenges. We found that the matricellular protein cellular communication network factor 2 (CCN2), also known as connective tissue growth factor (CTGF), is induced during a time course of overload-driven skeletal muscle hypertrophy in mice. To elucidate the role of CCN2 in mediating the hypertrophic response, we utilized genetically engineered mouse models for myofiber-specific CCN2 gain- and loss-of-function and then examined their response to mechanical stimuli through muscle overload. Interestingly, myofiber-specific deletion of CCN2 blunted muscle's hypertrophic response to overload without interfering with ECM deposition. On the other hand, when in excess through transgenic CCN2 overexpression, CCN2 was efficient in promoting overload-induced aberrant ECM accumulation without affecting myofiber growth. Altogether, our genetic approaches highlighted independent ECM and myofiber stress adaptation responses, and positioned CCN2 as a central mediator of both. Mechanistically, CCN2 acts by regulating focal adhesion kinase (FAK) mediated transduction of overload-induced extracellular signals, including interleukin 6 (IL6), and their regulatory impact on global protein synthesis in skeletal muscle. Overall, our study highlights the contribution of muscle-derived extracellular matrix factor CCN2 for proper hypertrophic muscle growth.
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Affiliation(s)
- Jennifer M Petrosino
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA
| | - Jacob Z Longenecker
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA
| | - Colin D Angell
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA
| | - Scott A Hinger
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA
| | - Colton R Martens
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA
| | - Federica Accornero
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA.
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11
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Saito Y, Chikenji TS. Diverse Roles of Cellular Senescence in Skeletal Muscle Inflammation, Regeneration, and Therapeutics. Front Pharmacol 2021; 12:739510. [PMID: 34552495 PMCID: PMC8450382 DOI: 10.3389/fphar.2021.739510] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 08/23/2021] [Indexed: 12/19/2022] Open
Abstract
Skeletal muscle undergoes vigorous tissue remodeling after injury. However, aging, chronic inflammatory diseases, sarcopenia, and neuromuscular disorders cause muscle loss and degeneration, resulting in muscular dysfunction. Cellular senescence, a state of irreversible cell cycle arrest, acts during normal embryonic development and remodeling after tissue damage; when these processes are complete, the senescent cells are eliminated. However, the accumulation of senescent cells is a hallmark of aging tissues or pathological contexts and may lead to progressive tissue degeneration. The mechanisms responsible for the effects of senescent cells have not been fully elucidated. Here, we review current knowledge about the beneficial and detrimental effects of senescent cells in tissue repair, regeneration, aging, and age-related disease, especially in skeletal muscle. We also discuss how senescence of muscle stem cells and muscle-resident fibro-adipogenic progenitors affects muscle pathologies or regeneration, and consider the possibility that immunosenescence leads to muscle pathogenesis. Finally, we explore senotherapy, the therapeutic targeting of senescence to treat age-related disease, from the standpoint of improving muscle regeneration.
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Affiliation(s)
- Yuki Saito
- Department of Anatomy, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Takako S Chikenji
- Department of Anatomy, Sapporo Medical University School of Medicine, Sapporo, Japan.,Department of Health Sciences, School of Medicine, Hokkaido University, Sapporo, Japan
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12
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Eftestøl E, Franchi MV, Kasper S, Flück M. JNK activation in TA and EDL muscle is load-dependent in rats receiving identical excitation patterns. Sci Rep 2021; 11:16405. [PMID: 34385505 PMCID: PMC8361015 DOI: 10.1038/s41598-021-94930-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 07/12/2021] [Indexed: 11/09/2022] Open
Abstract
As the excitation-contraction coupling is inseparable during voluntary exercise, the relative contribution of the mechanical and neural input on hypertrophy-related molecular signalling is still poorly understood. Herein, we use a rat in-vivo strength exercise model with an electrically-induced standardized excitation pattern, previously shown to induce a load-dependent increase in myonuclear number and hypertrophy, to study acute effects of load on molecular signalling. We assessed protein abundance and specific phosphorylation of the four protein kinases FAK, mTOR, p70S6K and JNK after 2, 10 and 28 min of a low- or high-load contraction, in order to assess the effects of load, exercise duration and muscle-type on their response to exercise. Specific phosphorylation of mTOR, p70S6K and JNK was increased after 28 min of exercise under the low- and high-load protocol. Elevated phosphorylation of mTOR and JNK was detectable already after 2 and 10 min of exercise, respectively, but greatest after 28 min of exercise, and JNK phosphorylation was highly load-dependent. The abundance of all four kinases was higher in TA compared to EDL muscle, p70S6K abundance was increased after exercise in a load-independent manner, and FAK and JNK abundance was reduced after 28 min of exercise in both the exercised and control muscles. In conclusion, the current study shows that JNK activation after a single resistance exercise is load-specific, resembling the previously reported degree of myonuclear accrual and muscle hypertrophy with repetition of the exercise stimulus.
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Affiliation(s)
- Einar Eftestøl
- Department of Biosciences, University of Oslo, Kristine Bonnevies hus, Blindernveien 31, 0371, Oslo, Norway.
| | - Martino V Franchi
- Laboratory for Muscle Plasticity, Department of Orthopaedics, University of Zürich, Zurich, Switzerland.,Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - Stephanie Kasper
- Laboratory for Muscle Plasticity, Department of Orthopaedics, University of Zürich, Zurich, Switzerland
| | - Martin Flück
- Laboratory for Muscle Plasticity, Department of Orthopaedics, University of Zürich, Zurich, Switzerland
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13
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Renzini A, Riera CS, Minic I, D’Ercole C, Lozanoska-Ochser B, Cedola A, Gigli G, Moresi V, Madaro L. Metabolic Remodeling in Skeletal Muscle Atrophy as a Therapeutic Target. Metabolites 2021; 11:517. [PMID: 34436458 PMCID: PMC8398298 DOI: 10.3390/metabo11080517] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 02/07/2023] Open
Abstract
Skeletal muscle is a highly responsive tissue, able to remodel its size and metabolism in response to external demand. Muscle fibers can vary from fast glycolytic to slow oxidative, and their frequency in a specific muscle is tightly regulated by fiber maturation, innervation, or external causes. Atrophic conditions, including aging, amyotrophic lateral sclerosis, and cancer-induced cachexia, differ in the causative factors and molecular signaling leading to muscle wasting; nevertheless, all of these conditions are characterized by metabolic remodeling, which contributes to the pathological progression of muscle atrophy. Here, we discuss how changes in muscle metabolism can be used as a therapeutic target and review the evidence in support of nutritional interventions and/or physical exercise as tools for counteracting muscle wasting in atrophic conditions.
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Affiliation(s)
- Alessandra Renzini
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
| | - Carles Sánchez Riera
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
| | - Isidora Minic
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
| | - Chiara D’Ercole
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
| | - Biliana Lozanoska-Ochser
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
| | - Alessia Cedola
- Institute of Nanotechnology, c/o Dipartimento di Fisica, National Research Council (CNR-NANOTEC), Sapienza University of Rome, 00185 Rome, Italy;
| | - Giuseppe Gigli
- Institute of Nanotechnology, c/o Campus Ecotekne, National Research Council (CNR-NANOTEC), Monteroni, 73100 Lecce, Italy;
| | - Viviana Moresi
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
- Institute of Nanotechnology, c/o Dipartimento di Fisica, National Research Council (CNR-NANOTEC), Sapienza University of Rome, 00185 Rome, Italy;
| | - Luca Madaro
- Unit of Histology and Medical Embryology, Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University of Rome, 00185 Rome, Italy; (A.R.); (C.S.R.); (I.M.); (C.D.); (B.L.-O.); (L.M.)
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14
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Ducret V, Richards AJ, Videlier M, Scalvenzi T, Moore KA, Paszkiewicz K, Bonneaud C, Pollet N, Herrel A. Transcriptomic analysis of the trade-off between endurance and burst-performance in the frog Xenopus allofraseri. BMC Genomics 2021; 22:204. [PMID: 33757428 PMCID: PMC7986297 DOI: 10.1186/s12864-021-07517-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 03/08/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Variation in locomotor capacity among animals often reflects adaptations to different environments. Despite evidence that physical performance is heritable, the molecular basis of locomotor performance and performance trade-offs remains poorly understood. In this study we identify the genes, signaling pathways, and regulatory processes possibly responsible for the trade-off between burst performance and endurance observed in Xenopus allofraseri, using a transcriptomic approach. RESULTS We obtained a total of about 121 million paired-end reads from Illumina RNA sequencing and analyzed 218,541 transcripts obtained from a de novo assembly. We identified 109 transcripts with a significant differential expression between endurant and burst performant individuals (FDR ≤ 0.05 and logFC ≥2), and blast searches resulted in 103 protein-coding genes. We found major differences between endurant and burst-performant individuals in the expression of genes involved in the polymerization and ATPase activity of actin filaments, cellular trafficking, proteoglycans and extracellular proteins secreted, lipid metabolism, mitochondrial activity and regulators of signaling cascades. Remarkably, we revealed transcript isoforms of key genes with functions in metabolism, apoptosis, nuclear export and as a transcriptional corepressor, expressed in either burst-performant or endurant individuals. Lastly, we find two up-regulated transcripts in burst-performant individuals that correspond to the expression of myosin-binding protein C fast-type (mybpc2). This suggests the presence of mybpc2 homoeologs and may have been favored by selection to permit fast and powerful locomotion. CONCLUSION These results suggest that the differential expression of genes belonging to the pathways of calcium signaling, endoplasmic reticulum stress responses and striated muscle contraction, in addition to the use of alternative splicing and effectors of cellular activity underlie locomotor performance trade-offs. Ultimately, our transcriptomic analysis offers new perspectives for future analyses of the role of single nucleotide variants, homoeology and alternative splicing in the evolution of locomotor performance trade-offs.
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Affiliation(s)
- Valérie Ducret
- UMR 7179 MECADEV, C.N.R.S/M.N.H.N., Département Adaptations du Vivant, 55 Rue Buffon, 75005, Paris, France.
| | - Adam J Richards
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
| | - Mathieu Videlier
- Functional Ecology Lab, Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada
| | - Thibault Scalvenzi
- Evolution, Génomes, Comportement & Ecologie, Université Paris-Saclay, CNRS, IRD, 91198, Gif-sur-Yvette, France
| | - Karen A Moore
- Exeter Sequencing Service, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Konrad Paszkiewicz
- Exeter Sequencing Service, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Camille Bonneaud
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
| | - Nicolas Pollet
- Evolution, Génomes, Comportement & Ecologie, Université Paris-Saclay, CNRS, IRD, 91198, Gif-sur-Yvette, France
| | - Anthony Herrel
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
- Evolutionary Morphology of Vertebrates, Ghent University, B-9000, Ghent, Belgium
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15
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Ben-Zeev T, Okun E. High-Intensity Functional Training: Molecular Mechanisms and Benefits. Neuromolecular Med 2021; 23:335-338. [PMID: 33386577 DOI: 10.1007/s12017-020-08638-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 11/25/2020] [Indexed: 10/22/2022]
Abstract
High-intensity interval training (HIIT) and strength exercise are known to improve health markers, such as cardiovascular health, metabolic health, and cognitive function, as well as to reduce all-cause mortality. High-Intensity Functional Training (HIFT) is a training paradigm derived from both HIIT and strength exercise to elicit greater muscle recruitment than repetitive aerobic exercises, thereby improving both cardiovascular fitness and strength parameters. Herein, we provide a focused review of the known molecular mechanisms that underlie the beneficial effects of HIFT on cardiovascular, metabolic, and cognitive functions.
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Affiliation(s)
- Tavor Ben-Zeev
- The Mina and Everard Goodman Faculty of Life Sciences, Ramat Gan, Israel.,The Paul Feder Laboratory on Alzheimer's Disease Research, Bar-Ilan University, Ramat Gan, Israel
| | - Eitan Okun
- The Mina and Everard Goodman Faculty of Life Sciences, Ramat Gan, Israel. .,The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Ramat Gan, Israel. .,The Paul Feder Laboratory on Alzheimer's Disease Research, Bar-Ilan University, Ramat Gan, Israel.
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16
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Emphasizing Task-Specific Hypertrophy to Enhance Sequential Strength and Power Performance. J Funct Morphol Kinesiol 2020; 5:jfmk5040076. [PMID: 33467291 PMCID: PMC7739346 DOI: 10.3390/jfmk5040076] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/04/2020] [Accepted: 10/21/2020] [Indexed: 12/15/2022] Open
Abstract
While strength is indeed a skill, most discussions have primarily considered structural adaptations rather than ultrastructural augmentation to improve performance. Altering the structural component of the muscle is often the aim of hypertrophic training, yet not all hypertrophy is equal; such alterations are dependent upon how the muscle adapts to the training stimuli and overall training stress. When comparing bodybuilders to strength and power athletes such as powerlifters, weightlifters, and throwers, while muscle size may be similar, the ability to produce force and power is often inequivalent. Thus, performance differences go beyond structural changes and may be due to the muscle's ultrastructural constituents and training induced adaptations. Relative to potentiating strength and power performances, eliciting specific ultrastructural changes should be a variable of interest during hypertrophic training phases. By focusing on task-specific hypertrophy, it may be possible to achieve an optimal amount of hypertrophy while deemphasizing metabolic and aerobic components that are often associated with high-volume training. Therefore, the purpose of this article is to briefly address different types of hypertrophy and provide directions for practitioners who are aiming to achieve optimal rather than maximal hypertrophy, as it relates to altering ultrastructural muscular components, to potentiate strength and power performance.
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17
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Mirzoev TM. Skeletal Muscle Recovery from Disuse Atrophy: Protein Turnover Signaling and Strategies for Accelerating Muscle Regrowth. Int J Mol Sci 2020; 21:ijms21217940. [PMID: 33114683 PMCID: PMC7663166 DOI: 10.3390/ijms21217940] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/08/2020] [Accepted: 10/23/2020] [Indexed: 12/15/2022] Open
Abstract
Skeletal muscle fibers have a unique capacity to adjust their metabolism and phenotype in response to alternations in mechanical loading. Indeed, chronic mechanical loading leads to an increase in skeletal muscle mass, while prolonged mechanical unloading results in a significant decrease in muscle mass (muscle atrophy). The maintenance of skeletal muscle mass is dependent on the balance between rates of muscle protein synthesis and breakdown. While molecular mechanisms regulating protein synthesis during mechanical unloading have been relatively well studied, signaling events implicated in protein turnover during skeletal muscle recovery from unloading are poorly defined. A better understanding of the molecular events that underpin muscle mass recovery following disuse-induced atrophy is of significant importance for both clinical and space medicine. This review focuses on the molecular mechanisms that may be involved in the activation of protein synthesis and subsequent restoration of muscle mass after a period of mechanical unloading. In addition, the efficiency of strategies proposed to improve muscle protein gain during recovery is also discussed.
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Affiliation(s)
- Timur M Mirzoev
- Myology Laboratory, Institute of Biomedical Problems RAS, Moscow 123007, Russia
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18
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Kumar A, Xie L, Ta CM, Hinton AO, Gunasekar SK, Minerath RA, Shen K, Maurer JM, Grueter CE, Abel ED, Meyer G, Sah R. SWELL1 regulates skeletal muscle cell size, intracellular signaling, adiposity and glucose metabolism. eLife 2020; 9:58941. [PMID: 32930093 PMCID: PMC7541086 DOI: 10.7554/elife.58941] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 09/07/2020] [Indexed: 12/26/2022] Open
Abstract
Maintenance of skeletal muscle is beneficial in obesity and Type 2 diabetes. Mechanical stimulation can regulate skeletal muscle differentiation, growth and metabolism; however, the molecular mechanosensor remains unknown. Here, we show that SWELL1 (Lrrc8a) functionally encodes a swell-activated anion channel that regulates PI3K-AKT, ERK1/2, mTOR signaling, muscle differentiation, myoblast fusion, cellular oxygen consumption, and glycolysis in skeletal muscle cells. LRRC8A over-expression in Lrrc8a KO myotubes boosts PI3K-AKT-mTOR signaling to supra-normal levels and fully rescues myotube formation. Skeletal muscle-targeted Lrrc8a KO mice have smaller myofibers, generate less force ex vivo, and exhibit reduced exercise endurance, associated with increased adiposity under basal conditions, and glucose intolerance and insulin resistance when raised on a high-fat diet, compared to wild-type (WT) mice. These results reveal that the LRRC8 complex regulates insulin-PI3K-AKT-mTOR signaling in skeletal muscle to influence skeletal muscle differentiation in vitro and skeletal myofiber size, muscle function, adiposity and systemic metabolism in vivo.
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Affiliation(s)
- Ashutosh Kumar
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, United States
| | - Litao Xie
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, United States
| | - Chau My Ta
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, United States
| | - Antentor O Hinton
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, United States.,Division of Endocrinology and Metabolism, Iowa City, United States
| | - Susheel K Gunasekar
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, United States
| | - Rachel A Minerath
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, United States.,Division of Cardiology, University of Iowa, Iowa City, United States
| | - Karen Shen
- Program in Physical Therapy and Departments of Neurology, Biomedical Engineering and Orthopedic Surgery, Washington University in St. Louis, St. Louis, United States
| | - Joshua M Maurer
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, United States
| | - Chad E Grueter
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, United States.,Division of Cardiology, University of Iowa, Iowa City, United States
| | - E Dale Abel
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, United States.,Division of Endocrinology and Metabolism, Iowa City, United States
| | - Gretchen Meyer
- Program in Physical Therapy and Departments of Neurology, Biomedical Engineering and Orthopedic Surgery, Washington University in St. Louis, St. Louis, United States
| | - Rajan Sah
- Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, United States
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19
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Monti E, Franchi MV, Badiali F, Quinlan JI, Longo S, Narici MV. The Time-Course of Changes in Muscle Mass, Architecture and Power During 6 Weeks of Plyometric Training. Front Physiol 2020; 11:946. [PMID: 32848873 PMCID: PMC7417646 DOI: 10.3389/fphys.2020.00946] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/14/2020] [Indexed: 12/23/2022] Open
Abstract
Purpose To investigate the time-course of changes in knee-extensors muscle mass, architecture and function in response to plyometric training (PLT) performed on a novel training device, the Tramp-Trainer. This machine consists in a trampoline connected to an inclined sledge which allows the performance of repeated jumps while the subject is sitting on a chair. Methods Eight healthy males (173.6 ± 4.7 cm, 69.7 ± 13.5 kg, 25.3 ± 4.6 years) underwent 6 weeks of bilateral PLT on the tramp-trainer machine. Training was performed three times per week (between 120 and 150 bounces per session). Knee-extensor maximum voluntary torque (MVT) and power, quadriceps femoris (QF) volume (VOL), cross-sectional area from the 20% to the 60% of femur length and CSAmean, together with vastus lateralis (VL) architecture (fascicle length, Lf, and pennation angle, PA) were assessed after 2, 4, and 6 weeks of PLT. Results All results are presented as changes versus baseline values. MVT increased by 17.8% (week 2, p < 0.001) and 22.2% (week 4, p < 0.01), respectively, and declined to 13.3% (p < 0.05) at week 6 of PLT. Power increased by 18.2% (week 4, p < 0.05) and 19.7% (week 6, p < 0.05). QF VOL increased by 4.7% (week 4, p < 0.05) and 5.8% (week 6, p < 0.01); VL VOL increased by 5.2%, (p < 0.05), 8.2%, (p < 0.01), and 9.6% (p < 0.05) at weeks 2, 4, and 6, respectively. An increase in Lf was detected already at wk 2 (2.2%, p < 0.05), with further increase at 4 and 6 weeks of PLT (4 and 4.4%, respectively, p < 0.01). PA increased by 5.8% (p < 0.05) at week 6. Significant positive correlations were found between CSAmean and Power (R2 = 0.46, p < 0.001) and between QF VOL and Power (R2 = 0.44, p < 0.024). Conclusions PLT induced rapid increases in muscle volume, fascicle length, pennation angle, torque and power in healthy younger adults. Notably, changes in VL VOL and Lf were detectable already after 2 weeks, followed by increases in knee extensors VOL and power from week 4 of PLT. Since the increase in CSAmean and QF VOL cannot fully explain the increment in muscle power, it is likely that other factors (such as adaptations in neural drive or tendon mechanical properties) may have contributed to such fucntional changes.
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Affiliation(s)
- Elena Monti
- Institute of Physiology, Department of Biomedical Sciences, University of Padua, Padua, Italy.,MRC-ARUK Centre for Musculoskeletal Ageing, University of Nottingham, Derby, United Kingdom
| | - Martino V Franchi
- Institute of Physiology, Department of Biomedical Sciences, University of Padua, Padua, Italy.,MRC-ARUK Centre for Musculoskeletal Ageing, University of Nottingham, Derby, United Kingdom
| | - Francesca Badiali
- MRC-ARUK Centre for Musculoskeletal Ageing, University of Nottingham, Derby, United Kingdom
| | - Jonathan I Quinlan
- MRC-ARUK Centre for Musculoskeletal Ageing, University of Nottingham, Derby, United Kingdom.,School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom.,NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham, NHS Foundation Trust and University of Birmingham, Birmingham, United Kingdom
| | - Stefano Longo
- MRC-ARUK Centre for Musculoskeletal Ageing, University of Nottingham, Derby, United Kingdom.,Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
| | - Marco V Narici
- Institute of Physiology, Department of Biomedical Sciences, University of Padua, Padua, Italy.,MRC-ARUK Centre for Musculoskeletal Ageing, University of Nottingham, Derby, United Kingdom.,CIR-Myo Myology Centre, Department of Biomedical Sciences, University of Padua, Padua, Italy
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20
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Marzuca-Nassr GN, Fortes MAS, Guimarães-Ferreira L, Murata GM, Vitzel KF, Vasconcelos DAA, Bassit RA, Curi R. Short-term creatine supplementation changes protein metabolism signaling in hindlimb suspension. ACTA ACUST UNITED AC 2019; 52:e8391. [PMID: 31596311 PMCID: PMC6787955 DOI: 10.1590/1414-431x20198391] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 08/21/2019] [Indexed: 01/04/2023]
Abstract
The effect of a short-term creatine supplementation on hindlimb suspension (HS)-induced muscle atrophy was investigated. Creatine monohydrate (5 g/kg b.w. per day) or placebo, divided in 2 daily doses, was given by oral gavage for 5 days. Rats were maintained in HS with dietary supplementation concomitantly for 5 days. Body weight, soleus and EDL muscle masses, and cross-sectional areas (CSA) of the muscle fibers were measured. Signaling pathways associated with skeletal muscle mass regulation (FST, MSTN, FAK, IGF-1, MGF, Akt, mTOR, atrogin-1, and MuRF1 expressions, and Akt, S6, GSK3B, and 4EBP1 proteins) were evaluated in the muscles. Soleus muscle exhibited more atrophy than the EDL muscle due to HS. Creatine supplementation attenuated the decrease of wet weight and increased p-4EBP1 protein in the EDL muscle of HS rats. Also, creatine increased mTOR and atrogin-1 expressions in the same muscle and condition. In the absence of HS, creatine supplementation increased FAK and decreased MGF expressions in the EDL muscle. Creatine attenuated the increase in FST expression due to HS in the soleus muscle. MuRF1 expression increased in the soleus muscle due to creatine supplementation in HS animals whereas atrogin-1 expression increased still further in this group compared with untreated HS rats. In conclusion, short-term creatine supplementation changed protein metabolism signaling in soleus and EDL muscles. However, creatine supplementation only slightly attenuated the mass loss of both muscles and did not prevent the CSA reduction and muscle strength decrease induced by HS for 5 days.
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Affiliation(s)
- G N Marzuca-Nassr
- Department of Internal Medicine, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile.,Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - M A S Fortes
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - L Guimarães-Ferreira
- Grupo de Estudos em Fisiologia Muscular e Performance Humana, Centro de Educação Física e Desportos, Universidade Federal do Espírito Santo, Vitória, ES, Brasil
| | - G M Murata
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - K F Vitzel
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil.,School of Health Sciences, College of Health, Massey University, Auckland, New Zealand
| | - D A A Vasconcelos
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - R A Bassit
- Departamento da Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - R Curi
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil.,Programa de Pós-graduação Interdisciplinar em Ciências da Saúde, Universidade Cruzeiro do Sul, São Paulo, SP, Brasil
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21
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Ferrié C, Kasper S, Wanivenhaus F, Flück M. Time course of costamere-related alterations in focal adhesion signaling and composition of rat soleus muscle after achilles tenotomy. Data Brief 2019; 25:103999. [PMID: 31463339 PMCID: PMC6706776 DOI: 10.1016/j.dib.2019.103999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 05/03/2019] [Accepted: 05/09/2019] [Indexed: 11/25/2022] Open
Abstract
Sarcolemma-based focal adhesions (costameres) are a central hub for the cytoskeletal anchoring of myofibrils and mechano-regulated signaling. Here we report the time course of alterations in focal adhesion-associated signaling and fiber composition in rat soleus muscle after Achilles tenotomy. The report includes data from tenotomized muscles and contralateral mock controls to expose whether muscle degeneration after tenotomy is due to the transection of the Achilles tendon, or circumjacent surgical manipulations of the tendon. With respect to the interpretation of the data regarding mechanistic implications of costamere-associated processes for surgical repair of the detached muscle-tendon complex the reader is referred to the accompanying research article 'Focal adhesion kinase coordinates costamere-related JNK signaling with muscle fiber transformation after Achilles tenotomy and tendon reconstruction' Ferrié et al., 2019.
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Affiliation(s)
- Céline Ferrié
- Laboratory for Muscle Plasticity, Department of Orthopedics, University of Zurich, Balgrist Campus, Zurich, Switzerland
| | - Stephanie Kasper
- Laboratory for Muscle Plasticity, Department of Orthopedics, University of Zurich, Balgrist Campus, Zurich, Switzerland
| | - Florian Wanivenhaus
- Department of Orthopedic Surgery, Balgrist University Hospital, Zurich, Switzerland
| | - Martin Flück
- Laboratory for Muscle Plasticity, Department of Orthopedics, University of Zurich, Balgrist Campus, Zurich, Switzerland
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22
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Boppart MD, Mahmassani ZS. Integrin signaling: linking mechanical stimulation to skeletal muscle hypertrophy. Am J Physiol Cell Physiol 2019; 317:C629-C641. [PMID: 31314586 DOI: 10.1152/ajpcell.00009.2019] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The α7β1-integrin is a transmembrane adhesion protein that connects laminin in the extracellular matrix (ECM) with actin in skeletal muscle fibers. The α7β1-integrin is highly expressed in skeletal muscle and is concentrated at costameres and myotendious junctions, providing the opportunity to transmit longitudinal and lateral forces across the membrane. Studies have demonstrated that α7-integrin subunit mRNA and protein are upregulated following eccentric contractions as a mechanism to reinforce load-bearing structures and resist injury with repeated bouts of exercise. It has been hypothesized for many years that the integrin can also promote protein turnover in a manner that can promote beneficial adaptations with resistance exercise training, including hypertrophy. This review provides basic information about integrin structure and activation and then explores its potential to serve as a critical mechanosensor and activator of muscle protein synthesis and growth. Overall, the hypothesis is proposed that the α7β1-integrin can contribute to mechanical-load induced skeletal muscle growth via an mammalian target of rapamycin complex 1-independent mechanism.
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Affiliation(s)
- Marni D Boppart
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois.,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Ziad S Mahmassani
- Department of Physical Therapy and Athletic Training, University of Utah, Salt Lake City, Utah
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Skeletal Muscle Fiber Adaptations Following Resistance Training Using Repetition Maximums or Relative Intensity. Sports (Basel) 2019; 7:sports7070169. [PMID: 31373325 PMCID: PMC6680702 DOI: 10.3390/sports7070169] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/04/2019] [Accepted: 07/07/2019] [Indexed: 11/16/2022] Open
Abstract
The purpose of the study was to compare the physiological responses of skeletal muscle to a resistance training (RT) program using repetition maximum (RM) or relative intensity (RISR). Fifteen well-trained males underwent RT 3 d·wk−1 for 10 weeks in either an RM group (n = 8) or RISR group (n = 7). The RM group achieved a relative maximum each day, while the RISR group trained based on percentages. The RM group exercised until muscular failure on each exercise, while the RISR group did not reach muscular failure throughout the intervention. Percutaneous needle biopsies of the vastus lateralis were obtained pre-post the training intervention, along with ultrasonography measures. Dependent variables were: Fiber type-specific cross-sectional area (CSA); anatomical CSA (ACSA); muscle thickness (MT); mammalian target of rapamycin (mTOR); adenosine monophosphate protein kinase (AMPK); and myosin heavy chains (MHC) specific for type I (MHC1), type IIA (MHC2A), and type IIX (MHC2X). Mixed-design analysis of variance and effect size using Hedge’s g were used to assess within- and between-group alterations. RISR statistically increased type I CSA (p = 0.018, g = 0.56), type II CSA (p = 0.012, g = 0.81), ACSA (p = 0.002, g = 0.53), and MT (p < 0.001, g = 1.47). RISR also yielded a significant mTOR reduction (p = 0.031, g = −1.40). Conversely, RM statistically increased only MT (p = 0.003, g = 0.80). Between-group effect sizes supported RISR for type I CSA (g = 0.48), type II CSA (g = 0.50), ACSA (g = 1.03), MT (g = 0.72), MHC2X (g = 0.31), MHC2A (g = 0.87), and MHC1 (g = 0.59); with all other effects being of trivial magnitude (g < 0.20). Our results demonstrated greater adaptations in fiber size, whole-muscle size, and several key contractile proteins when using RISR compared to RM loading paradigms.
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24
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Ferrié C, Kasper S, Wanivenhaus F, Flück M. Focal adhesion kinase coordinates costamere-related JNK signaling with muscle fiber transformation after Achilles tenotomy and tendon reconstruction. Exp Mol Pathol 2019; 108:42-56. [PMID: 30879953 DOI: 10.1016/j.yexmp.2019.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 01/29/2019] [Accepted: 03/12/2019] [Indexed: 01/24/2023]
Abstract
Achilles tendon rupture necessitates rapid tendon reattachment to reinstate plantar flexion before affected muscles deteriorate through muscle fiber atrophy and transformation. The implicated process may involve alterations in sarcolemmal sites of myofibril attachment (costameres), which control myofibrillogenesis via a mechano-regulated mechanism through integrin-associated focal adhesion kinase (FAK). We assessed the contribution of FAK to alterations in fiber type composition and expression of costamere-associated structural proteins, the phosphorylation status of Y397-FAK and downstream mTOR/JNK-P70S6K hypertrophy signaling in rat soleus muscle after Achilles tenotomy and tendon repair. Achilles tenotomy induced a profound deterioration of muscle composition 14 days, but not 4 days, following tendon release, comprising specifically increased area percentages of fast type fibers, fibers with internal nuclei, and connective tissue. Concomitantly, expression of costameric proteins FAK and meta-vinculin, and phosphorylation of T421/S424-P70S6K and T183/Y185-JNK was elevated, all of which was mitigated by tendon reattachment immediately after release. Overexpression of FAK in soleus muscle fibers and reattachment corrected the expression of meta- and gamma-vinculin isoforms to the lower levels in mock controls while further enhancing T183/Y185-JNK phosphorylation and levels of FAK C-terminus-related inhibitory proteins. Co-overexpression of the FAK inhibitor, FRNK, lowered FAK-overexpression driven Y397-FAK phosphorylation and T183/Y185-JNK phosphorylation. FAK levels correlated to molecular and cellular hallmarks of fiber degeneration. The findings demarcate the window between 4 and 14 days after tenotomy as costamere-dependent muscle transformation process, and expose that FAK overexpression prevents molecular aspects of the pathology which within the study limitations does not result in the mitigation of muscle fiber degeneration.250 words.
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Affiliation(s)
- Céline Ferrié
- Laboratory for Muscle Plasticity, Department of Orthopedics, University of Zurich, Balgrist Campus, Zurich, Switzerland
| | - Stephanie Kasper
- Laboratory for Muscle Plasticity, Department of Orthopedics, University of Zurich, Balgrist Campus, Zurich, Switzerland
| | - Florian Wanivenhaus
- Department of Orthopedic Surgery, Balgrist University Hospital, Zurich, Switzerland
| | - Martin Flück
- Laboratory for Muscle Plasticity, Department of Orthopedics, University of Zurich, Balgrist Campus, Zurich, Switzerland.
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Olsen LA, Nicoll JX, Fry AC. The skeletal muscle fiber: a mechanically sensitive cell. Eur J Appl Physiol 2019; 119:333-349. [PMID: 30612167 DOI: 10.1007/s00421-018-04061-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 12/21/2018] [Indexed: 12/12/2022]
Abstract
The plasticity of skeletal muscle, whether an increase in size, change in metabolism, or alteration in structural properties, is in a continuous state of flux largely dependent upon physical activity. Much of the past research has expounded upon these ever-changing aspects of the muscle fiber following exercise. Specifically, endocrine and paracrine signaling have been heavily investigated lending to much of the past literature comprised of such endocrinological dynamics following muscle activity. Mechanotransduction, the ability of a cell to convert a mechanical stimulus into an intracellular biochemical response, has garnered much less attention. Recent work, however, has demonstrated the physical continuity of the muscle fiber, specifically demonstrating a continuous physical link between the extracellular matrix (ECM), cytoskeleton, and nuclear matrix as a means to rapidly regulate gene expression following a mechanical stimulus. Similarly, research has shown mechanical stimuli to directly influence cytoplasmic signaling whether through oxidative adaptations, increased muscle size, or enhanced muscle integrity. Regrettably, minimal research has investigated the role that exercise may play within the mechanotransducing signaling cascades. This proposed line of study may prove paramount as muscle-related diseases greatly impact one's ability to lead an independent lifestyle along with contributing a substantial burden upon the economy. Thus, this review explores both biophysical and biochemical mechanotransduction, and how these signaling pathways may be influenced following exercise.
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Affiliation(s)
- Luke A Olsen
- Biomedical Sciences, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Justin X Nicoll
- Department of Kinesiology, California State University, Northridge, CA, 91330-8287, USA
| | - Andrew C Fry
- Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, KS, 66045, USA.
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26
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Gorgey AS, Witt O, O’Brien L, Cardozo C, Chen Q, Lesnefsky EJ, Graham ZA. Mitochondrial health and muscle plasticity after spinal cord injury. Eur J Appl Physiol 2018; 119:315-331. [DOI: 10.1007/s00421-018-4039-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 11/22/2018] [Indexed: 01/15/2023]
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Mirzoev TM, Shenkman BS. Regulation of Protein Synthesis in Inactivated Skeletal Muscle: Signal Inputs, Protein Kinase Cascades, and Ribosome Biogenesis. BIOCHEMISTRY (MOSCOW) 2018; 83:1299-1317. [PMID: 30482143 DOI: 10.1134/s0006297918110020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Disuse atrophy of skeletal muscles is characterized by a significant decrease in the mass and size of muscle fibers. Disuse atrophy develops as a result of prolonged reduction in the muscle functional activity caused by bed rest, limb immobilization, and real or simulated microgravity. Disuse atrophy is associated with the downregulation of protein biosynthesis and simultaneous activation of protein degradation. This review is focused on the key molecular mechanisms regulating the rate of protein synthesis in mammalian skeletal muscles during functional unloading.
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Affiliation(s)
- T M Mirzoev
- Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, 123007, Russia.
| | - B S Shenkman
- Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, 123007, Russia
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28
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Exercise and the control of muscle mass in human. Pflugers Arch 2018; 471:397-411. [DOI: 10.1007/s00424-018-2217-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 10/02/2018] [Accepted: 10/04/2018] [Indexed: 12/19/2022]
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29
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Flück M, Viecelli C, Bapst AM, Kasper S, Valdivieso P, Franchi MV, Ruoss S, Lüthi JM, Bühler M, Claassen H, Hoppeler H, Gerber C. Knee Extensors Muscle Plasticity Over a 5-Years Rehabilitation Process After Open Knee Surgery. Front Physiol 2018; 9:1343. [PMID: 30337877 PMCID: PMC6178139 DOI: 10.3389/fphys.2018.01343] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 09/06/2018] [Indexed: 01/26/2023] Open
Abstract
We investigated molecular and cellular parameters which set metabolic and mechanical functioning of knee extensor muscles in the operated and contralateral control leg of 9 patients with a chronically insufficient anterior cruciate ligament (ACL; 26.6 ± 8.3 years, 8 males, 1 female) after open reconstructive surgery (week 0), after ambulant physiotherapy under cast immobilization (week 9), succeeding rehabilitation training (up to week 26), and subsequent voluntary physical activity (week 260). Clinical indices of knee function in the operated leg were improved at 52 weeks and remained at a comparable level at week 260. CSA of the quadriceps (-18%), MCSA of muscle fibers (-24%), and capillary-to-fiber ratio (-24%) in m. vastus lateralis from the ACL insufficient leg were lower at week 0 than reference values in the contralateral leg at week 260. Slow type fiber percentage (-35%) and mitochondrial volume density (-39%) were reduced in m. vastus lateralis from the operated leg at weeks 9 and 26. Composition alterations in the operated leg exceeded those in the contralateral leg and, with the exception of the volume density of subsarcolemmal mitochondria, returned to the reference levels at week 260. Leg-specific deterioration of metabolic characteristics in the vasti from the operated leg was reflected by the down-regulation of mitochondrial respiration complex I-III markers (-41-57%) at week 9. After rehabilitation training at week 26, the specific Y397 phosphorylation of focal adhesion kinase (FAK), which is a proxy for mechano-regulation, was elevated by 71% in the operated leg but not in the contralateral leg, which had performed strengthening type exercise during ambulant physiotherapy. Total FAK protein and Y397 phosphorylation levels were lowered in both legs at week 26 resulting in positive correlations with mitochondrial volume densities and mitochondrial protein levels. The findings emphasize that a loss of mechanical and metabolic characteristics in knee extensor muscle remains detectable years after untreated ACL rupture, which may be aggravated in the post-operative phase by the deterioration of slow-oxidative characteristics after reconstruction due to insufficient load-bearing muscle activity. The reestablishment of muscle composition subsequent to years of voluntary physical activity reinforces that slow-to-fast fiber transformation is reversible in humans.
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Affiliation(s)
- Martin Flück
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Claudio Viecelli
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Andreas M Bapst
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Stephanie Kasper
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Paola Valdivieso
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Martino V Franchi
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Severin Ruoss
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jean-Marc Lüthi
- Department of Orthopedic Surgery, Inselspital Bern, Bern, Switzerland
| | - Martin Bühler
- Department of Orthopedic Surgery, Inselspital Bern, Bern, Switzerland
| | | | - Hans Hoppeler
- Department of Anatomy, University of Bern, Bern, Switzerland
| | - Christian Gerber
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Orthopedic Surgery, Inselspital Bern, Bern, Switzerland
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30
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Rittweger J, Albracht K, Flück M, Ruoss S, Brocca L, Longa E, Moriggi M, Seynnes O, Di Giulio I, Tenori L, Vignoli A, Capri M, Gelfi C, Luchinat C, Francheschi C, Bottinelli R, Cerretelli P, Narici M. Sarcolab pilot study into skeletal muscle's adaptation to long-term spaceflight. NPJ Microgravity 2018; 4:18. [PMID: 30246141 PMCID: PMC6141586 DOI: 10.1038/s41526-018-0052-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 07/04/2018] [Accepted: 07/10/2018] [Indexed: 12/31/2022] Open
Abstract
Spaceflight causes muscle wasting. The Sarcolab pilot study investigated two astronauts with regards to plantar flexor muscle size, architecture, and function, and to the underlying molecular adaptations in order to further the understanding of muscular responses to spaceflight and exercise countermeasures. Two crew members (A and B) spent 6 months in space. Crew member A trained less vigorously than B. Postflight, A showed substantial decrements in plantar flexor volume, muscle architecture, in strength and in fiber contractility, which was strongly mitigated in B. The difference between these crew members closely reflected FAK-Y397 abundance, a molecular marker of muscle's loading history. Moreover, crew member A showed downregulation of contractile proteins and enzymes of anaerobic metabolism, as well as of systemic markers of energy and protein metabolism. However, both crew members exhibited decrements in muscular aerobic metabolism and phosphate high energy transfer. We conclude that countermeasures can be effective, particularly when resistive forces are of sufficient magnitude. However, to fully prevent space-related muscular deterioration, intersubject variability must be understood, and intensive exercise countermeasures programs seem mandatory. Finally, proteomic and metabolomic analyses suggest that exercise benefits in space may go beyond mere maintenance of muscle mass, but rather extend to the level of organismic metabolism.
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Affiliation(s)
- Jörn Rittweger
- 1Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.,2Department of Pediatrics and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Kirsten Albracht
- 3Faculty of Medical Engineering and Technomathematics, FH Aachen University of Applied Science Aachen, Aachen, Germany.,4Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany
| | - Martin Flück
- 5Department of Orthopaedics, University of Zürich, Zürich, Switzerland
| | - Severin Ruoss
- 5Department of Orthopaedics, University of Zürich, Zürich, Switzerland
| | - Lorenza Brocca
- 6Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Emanuela Longa
- 6Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | | | - Olivier Seynnes
- 8Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Irene Di Giulio
- 9Centre for Human and Applied Physiological Sciences, King's College London, London, UK
| | - Leonardo Tenori
- 10Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Alessia Vignoli
- CERM Centro di Ricerca di Risonanze Magnetiche, Florence, Italy
| | - Miriam Capri
- 12Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Cecilia Gelfi
- 13Department of Biomedical Sciences for Health, University of Milan, Milano, Italy
| | | | - Claudio Francheschi
- 12Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Roberto Bottinelli
- 6Department of Molecular Medicine, University of Pavia, Pavia, Italy.,14Fondazione Salvatore Maugeri (IRCSS), Scientific Institute of Pavia, Pavia, Italy
| | | | - Marco Narici
- 15Department of Biomedical Sciences, University of Padova, Padova, Italy
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31
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Franchi MV, Ruoss S, Valdivieso P, Mitchell KW, Smith K, Atherton PJ, Narici MV, Flück M. Regional regulation of focal adhesion kinase after concentric and eccentric loading is related to remodelling of human skeletal muscle. Acta Physiol (Oxf) 2018; 223:e13056. [PMID: 29438584 DOI: 10.1111/apha.13056] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 01/31/2018] [Accepted: 02/07/2018] [Indexed: 12/31/2022]
Abstract
AIMS We assessed focal adhesion kinase (FAK) response to concentric (CON) vs eccentric (ECC) resistance training (RT) at two vastus lateralis (VL) sites, and the relationships between FAK, muscle protein synthesis (MPS) and morphological remodelling. METHODS Six young males trained both legs unilaterally 3 times/week for 8 weeks; one leg performed CON RT, the contralateral performed ECC RT. Muscle biopsies were collected after training from VL mid-belly (MID) and distal (distal) sites at 0, 4, 8 weeks. Focal adhesion kinase content and activation were evaluated by immunoblotting. MPS was assessed by deuterium oxide tracer; morphological adaptations were evaluated by ultrasound and DXA. RESULTS pY397-FAK 8 weeks levels were ~4-fold greater after ECC at the distal site compared to CON (P < .05); pY397FAK to total FAK ratio was greater in ECC vs CON at 4 (~2.2-fold, P < .05) and 8 weeks (~9-fold, P < .001) at the distal site. Meta-vinculin was found transiently increased at 4 weeks at the distal site only after ECC RT. ECC presented greater fascicle length (Lf) increases (10.5% vs 4%), whereas CON showed greater in pennation angle (PA) changes (12.3% vs 2.1%). MPS did not differ between exercise types or muscle sites at all time points. distal pY397-FAK and pY397-FAK/FAK values correlated to changes in Lf at 8 weeks (r = .76, P < .01 and r = .66, P < .05 respectively). CONCLUSION Focal adhesion kinase phosphorylation was greater at 8 weeks after ECC RT and was muscle region-specific. FAK activity correlated to contraction-dependent architectural remodelling, suggesting a potential role of FAK in orienting muscle structural changes in response to distinct mechanical stimuli.
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Affiliation(s)
- M V Franchi
- Laboratory for Muscle Plasticity, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- MRC-ARUK Centre for Musculoskeletal Ageing, Royal Derby Hospital, University of Nottingham, Derby, UK
| | - S Ruoss
- Laboratory for Muscle Plasticity, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - P Valdivieso
- Laboratory for Muscle Plasticity, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - K W Mitchell
- MRC-ARUK Centre for Musculoskeletal Ageing, Royal Derby Hospital, University of Nottingham, Derby, UK
| | - K Smith
- MRC-ARUK Centre for Musculoskeletal Ageing, Royal Derby Hospital, University of Nottingham, Derby, UK
| | - P J Atherton
- MRC-ARUK Centre for Musculoskeletal Ageing, Royal Derby Hospital, University of Nottingham, Derby, UK
| | - M V Narici
- MRC-ARUK Centre for Musculoskeletal Ageing, Royal Derby Hospital, University of Nottingham, Derby, UK
- Department of Biomedical Sciences, Institute of Physiology, University of Padua, Padua, Italy
| | - M Flück
- Laboratory for Muscle Plasticity, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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32
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Bamman MM, Roberts BM, Adams GR. Molecular Regulation of Exercise-Induced Muscle Fiber Hypertrophy. Cold Spring Harb Perspect Med 2018; 8:cshperspect.a029751. [PMID: 28490543 DOI: 10.1101/cshperspect.a029751] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Skeletal muscle hypertrophy is a widely sought exercise adaptation to counteract the muscle atrophy of aging and disease, or to improve athletic performance. While this desired muscle enlargement is a well-known adaptation to resistance exercise training (RT), the mechanistic underpinnings are not fully understood. The purpose of this review is thus to provide the reader with a summary of recent advances in molecular mechanisms-based on the most current literature-that are thought to promote RT-induced muscle hypertrophy. We have therefore focused this discussion on the following areas of fertile investigation: ribosomal function and biogenesis, muscle stem (satellite) cell activity, transcriptional regulation, mechanotransduction, and myokine signaling.
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Affiliation(s)
- Marcas M Bamman
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294.,UAB Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35205.,Geriatric Research, Education, and Clinical Center, Veterans' Affairs Medical Center, Birmingham, Alabama 35233
| | - Brandon M Roberts
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294.,UAB Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35205
| | - Gregory R Adams
- Department of Physiology and Biophysics, University of California Irvine, Irvine, California 92617
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33
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Carraro U. Exciting perspectives for Translational Myology in the Abstracts of the 2018Spring PaduaMuscleDays: Giovanni Salviati Memorial - Chapter IV - Abstracts of March 17, 2018. Eur J Transl Myol 2018; 28:7366. [PMID: 30057728 PMCID: PMC6047882 DOI: 10.4081/ejtm.2018.7366] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 02/20/2018] [Indexed: 02/08/2023] Open
Abstract
Myologists working in Padua (Italy) were able to continue a half-century tradition of studies of skeletal muscles, that started with a research on fever, specifically if and how skeletal muscle contribute to it by burning bacterial toxin. Beside main publications in high-impact-factor journals by Padua myologists, I hope to convince readers (and myself) of the relevance of the editing Basic and Applied Myology (BAM), retitled from 2010 European Journal of Translational Myology (EJTM), of the institution of the Interdepartmental Research Center of Myology of the University of Padova (CIR-Myo), and of a long series of International Conferences organized in Euganei Hills and Padova, that is, the PaduaMuscleDays. The 2018Spring PaduaMuscleDays (2018SpPMD), were held in Euganei Hills and Padua (Italy), in March 14-17, and were dedicated to Giovanni Salviati. The main event of the “Giovanni Salviati Memorial”, was held in the Aula Guariento, Accademia Galileiana di Scienze, Lettere ed Arti of Padua to honor a beloved friend and excellent scientist 20 years after his premature passing. Using the words of Prof. Nicola Rizzuto, we all share his believe that Giovanni “will be remembered not only for his talent and originality as a biochemist, but also for his unassuming and humanistic personality, a rare quality in highly successful people like Giovanni. The best way to remember such a person is to gather pupils and colleagues, who shared with him the same scientific interests and ask them to discuss recent advances in their own fields, just as Giovanni have liked to do”. Since Giovanni’s friends sent many abstracts still influenced by their previous collaboration with him, all the Sessions of the 2018SpPMD reflect both to the research aims of Giovanni Salviati and the traditional topics of the PaduaMuscleDays, that is, basics and applications of physical, molecular and cellular strategies to maintain or recover functions of skeletal muscles. The translational researches summarized in the 2018SpPMD Abstracts are at the appropriate high level to attract endorsement of Ethical Committees, the interest of International Granting Agencies and approval for publication in top quality international journals. The abstracts of the presentations of the March 16, 2018 Padua Muscle Day and those of the remaining Posters are listed in this chapter IV. The Author Index of the 2018Spring PaduaMuscleDays follows at page 78.
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Affiliation(s)
- Ugo Carraro
- Laboratory of Translational Myology, Department of Biomedical Sciences, University of Padova.,A&C M-C Foundation for Translational Myology, Padova.,IRCCS Fondazione Ospedale San Camillo, Venezia-Lido, Italy
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Ruoss S, Möhl CB, Benn MC, von Rechenberg B, Wieser K, Meyer DC, Gerber C, Flück M. Costamere protein expression and tissue composition of rotator cuff muscle after tendon release in sheep. J Orthop Res 2018; 36:272-281. [PMID: 28574610 PMCID: PMC5873452 DOI: 10.1002/jor.23624] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 05/24/2017] [Indexed: 02/04/2023]
Abstract
Previous studies suggested that degradation of contractile tissue requires cleavage of the costamere, a structural protein complex that holds sarcomeres in place. This study examined if costamere turnover is affected by a rotator cuff tear in a previously established ovine model. We found the activity of focal adhesion kinase (FAK), a main regulator of costamere turnover, was unchanged at 2 weeks but decreased by 27% 16 weeks after surgical release of the infraspinatus tendon. This was accompanied by cleavage of the costamere protein talin into a 190 kDa fragment while full length talin remained unchanged. At 2 weeks after tendon release, muscle volume decreased by 17 cm3 from an initial 185 cm3 , the fatty tissue volume was halved, and the contractile tissue volume remained unchanged. After 16 weeks, the muscle volume decreased by 36 cm3 , contractile tissue was quantitatively lost, and the fat content increased by 184%. Nandrolone administration mitigated the loss of contractile tissue by 26% and prevented fat accumulation, alterations in FAK activity, and talin cleavage. Taken together, these findings imply that muscle remodeling after tendon release occurs in two stages. The early decrease of muscle volume is associated with reduction of fat; while, the second stage is characterized by substantial loss of contractile tissue accompanied by massive fat accumulation. Regulation of costamere turnover is associated with the loss of contractile tissue and seems to be impacted by nandrolone treatment. Clinically, the costamere may represent a potential intervention target to mitigate muscle loss after a rotator cuff tear. © 2017 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 36:272-281, 2018.
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Affiliation(s)
- Severin Ruoss
- Laboratory for Muscle Plasticity, Balgrist CampusUniversity of ZurichZurichSwitzerland
| | - Christoph B. Möhl
- Laboratory for Muscle Plasticity, Balgrist CampusUniversity of ZurichZurichSwitzerland
| | - Mario C. Benn
- Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | | | - Karl Wieser
- Department of Orthopaedics, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Dominik C. Meyer
- Department of Orthopaedics, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Christian Gerber
- Department of Orthopaedics, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Martin Flück
- Laboratory for Muscle Plasticity, Balgrist CampusUniversity of ZurichZurichSwitzerland
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35
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Fortes MAS, Scervino MVM, Marzuca-Nassr GN, Vitzel KF, da Justa Pinheiro CH, Curi R. Hypertrophy Stimulation at the Onset of Type I Diabetes Maintains the Soleus but Not the EDL Muscle Mass in Wistar Rats. Front Physiol 2017; 8:830. [PMID: 29123487 PMCID: PMC5662641 DOI: 10.3389/fphys.2017.00830] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/06/2017] [Indexed: 12/17/2022] Open
Abstract
Diabetes mellitus induces a reduction in skeletal muscle mass and strength. Strength training is prescribed as part of treatment since it improves glycemic control and promotes increase of skeletal muscle mass. The mechanisms involved in overload-induced muscle hypertrophy elicited at the establishment of the type I diabetic state was investigated in Wistar rats. The purpose was to examine whether the overload-induced hypertrophy can counteract the hypotrophy associated to the diabetic state. The experiments were performed in oxidative (soleus) or glycolytic (EDL) muscles. PI3K/Akt/mTOR protein synthesis pathway was evaluated 7 days after overload-induced hypertrophy of soleus and of EDL muscles. The mRNA expression of genes associated with different signaling pathways that control muscle hypertrophy was also evaluated: mechanotransduction (FAK), Wnt/β-catenin, myostatin, and follistatin. The soleus and EDL muscles when submitted to overload had similar hypertrophic responses in control and diabetic animals. The increase of absolute and specific twitch and tetanic forces had the same magnitude as muscle hypertrophic response. Hypertrophy of the EDL muscle from diabetic animals mostly involved mechanical loading-stimulated PI3K/Akt/mTOR pathway besides the reduced activation of AMP-activated protein kinase (AMPK) and decrease of myostatin expression. Hypertrophy was more pronounced in the soleus muscle of diabetic animals due to a more potent activation of rpS6 and increased mRNA expression of insulin-like growth factor-1 (IGF-1), mechano-growth factor (MGF) and follistatin, and decrease of myostatin, MuRF-1 and atrogin-1 contents. The signaling changes enabled the soleus muscle mass and force of the diabetic rats to reach the values of the control group.
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Affiliation(s)
- Marco A S Fortes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Maria V M Scervino
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gabriel N Marzuca-Nassr
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Department of Internal Medicine, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile
| | - Kaio F Vitzel
- School of Health Sciences, College of Health, Massey University, Albany, New Zealand
| | - Carlos H da Justa Pinheiro
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Interdisciplinary Post-Graduate Program in Health Sciences, Cruzeiro do Sul University, São Paulo, Brazil
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36
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Kido K, Ato S, Yokokawa T, Makanae Y, Sato K, Fujita S. Acute resistance exercise-induced IGF1 expression and subsequent GLUT4 translocation. Physiol Rep 2017; 4:4/16/e12907. [PMID: 27550988 PMCID: PMC5002915 DOI: 10.14814/phy2.12907] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 07/21/2016] [Indexed: 11/29/2022] Open
Abstract
Acute aerobic exercise (AE) is a major physiological stimulus for skeletal muscle glucose uptake through activation of 5′ AMP‐activated protein kinase (AMPK). However, the regulation of glucose uptake by acute resistance exercise (RE) remains unclear. To investigate the intracellular regulation of glucose uptake after acute RE versus acute AE, male Sprague–Dawley rats were divided into three groups: RE, AE, or nonexercise control. After fasting for 12 h overnight, the right gastrocnemius muscle in the RE group was exercised at maximum isometric contraction via percutaneous electrical stimulation (3 × 10 sec, 5 sets). The AE group ran on a treadmill (25 m/min, 60 min). Muscle samples were taken 0, 1, and 3 h after completion of the exercises. AMPK, Ca2+/calmodulin‐dependent protein kinase II, and TBC1D1 phosphorylation were increased immediately after both forms of exercise and returned to baseline levels by 3 h. Muscle IGF1 expression was increased by RE but not AE, and maintained until 3 h after RE. Additionally, Akt and AS160 phosphorylation were sustained for 3 h after RE, whereas they returned to baseline levels by 3 h after AE. Similarly, GLUT4 translocation remained elevated 3 h after RE, although it returned to the baseline level by 3 h after AE. Overall, this study showed that AMPK/TBC1D1 and IGF1/Akt/AS160 signaling were enhanced by acute RE, and that GLUT4 translocation after acute RE was more prolonged than after acute AE. These results suggest that acute RE‐induced increases in intramuscular IGF1 expression might be a distinct regulator of GLUT4 translocation.
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Affiliation(s)
- Kohei Kido
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan
| | - Satoru Ato
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan
| | - Takumi Yokokawa
- Laboratory of Sports and Exercise Medicine, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan
| | - Yuhei Makanae
- Department of Physical Education, National Defense Academy, Yokosuka, Japan
| | - Koji Sato
- Graduate School of Human Development and Environment, Kobe University, Kobe, Japan
| | - Satoshi Fujita
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan
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37
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Schilder RJ. (How) do animals know how much they weigh? ACTA ACUST UNITED AC 2017; 219:1275-82. [PMID: 27208031 DOI: 10.1242/jeb.120410] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 03/14/2016] [Indexed: 12/21/2022]
Abstract
Animal species varying in size and musculoskeletal design all support and move their body weight. This implies the existence of evolutionarily conserved feedback between sensors that produce quantitative signals encoding body weight and proximate determinants of musculoskeletal designs. Although studies at the level of whole organisms and tissue morphology and function clearly indicate that musculoskeletal designs are constrained by body weight variation, the corollary to this - i.e. that the molecular-level composition of musculoskeletal designs is sensitive to body weight variation - has been the subject of only minimal investigation. The main objective of this Commentary is to briefly summarize the former area of study but, in particular, to highlight the latter hypothesis and the relevance of understanding the mechanisms that control musculoskeletal function at the molecular level. Thus, I present a non-exhaustive overview of the evidence - drawn from different fields of study and different levels of biological organization - for the existence of body weight sensing mechanism(s).
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Affiliation(s)
- Rudolf J Schilder
- Department of Entomology and Biology, Pennsylvania State University, 501 Ag Sci Ind Bldg, University Park, PA 16802, USA
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38
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Ropka-Molik K, Stefaniuk-Szmukier M, Z˙ukowski K, Piórkowska K, Bugno-Poniewierska M. Exercise-induced modification of the skeletal muscle transcriptome in Arabian horses. Physiol Genomics 2017; 49:318-326. [DOI: 10.1152/physiolgenomics.00130.2016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 04/21/2017] [Accepted: 04/21/2017] [Indexed: 01/20/2023] Open
Abstract
It has been found that Arabian and Thoroughbred horses differ in muscle fiber structure and thus in physiological changes occurring in muscles during exercise. The aim of the present study was to identify the global gene expression modifications that occur in skeletal muscle following a training regime to prepare for flat racing. Whole transcriptomes of muscle (gluteus medius) were compared between three time points of tissue collection: T0 (untrained horses), T1 (horses after intense gallop phase), and T2 (horses at the end of racing season), 23 samples in total. The numerous groups of exercise-regulated differentially expressed genes (DEGs) were related to muscle cell structure and signaling and included insulin-like growth factor 1 receptor ( IGF1R), insulin receptor ( INSR), transforming growth factor beta receptors 1 and 2 ( TGFBR1, TGFBR2), vascular endothelial growth factor B ( VEGFB); epidermal growth factor ( EGF), hepatocyte growth factor ( HGF), and vascular endothelial growth factor D ( FIGF). In Arabian horses, exercise modified the expression of genes belonging to the PPAR signaling pathway (e.g., PPARA, PPARD, and PLIN2), calcium signaling pathway, and pathways associated with metabolic processes (e.g., oxidative phosphorylation, fatty acid metabolism, glycolysis/gluconeogenesis, and citrate cycle). According to detected gene expression modifications, our results suggested that in Arabian horses, exercise switches energy generation toward fatty acid utilization and enhances glycogen transport and calcium signaling. The use of the RNA-Seq approach in analyzing the skeletal muscle transcriptome allowed for the proposal of a panel of new candidate genes potentially related to body homeostasis maintenance and racing performance in Arabian horses.
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Affiliation(s)
- Katarzyna Ropka-Molik
- Department of Genomics and Animal Molecular Biology, National Research Institute of Animal Production, Cracow, Poland
| | - Monika Stefaniuk-Szmukier
- Department of Horse Breeding, Institute of Animal Science, University of Agriculture in Cracow, Poland; and
| | - Kacper Z˙ukowski
- Department of Animal Genetics and Breeding, National Research Institute of Animal Production, Cracow, Poland
| | - Katarzyna Piórkowska
- Department of Genomics and Animal Molecular Biology, National Research Institute of Animal Production, Cracow, Poland
| | - Monika Bugno-Poniewierska
- Department of Genomics and Animal Molecular Biology, National Research Institute of Animal Production, Cracow, Poland
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Kido K, Yokokawa T, Ato S, Sato K, Fujita S. Effect of resistance exercise under conditions of reduced blood insulin on AMPKα Ser485/491 inhibitory phosphorylation and AMPK pathway activation. Am J Physiol Regul Integr Comp Physiol 2017; 313:R110-R119. [PMID: 28515080 DOI: 10.1152/ajpregu.00063.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/02/2017] [Accepted: 05/15/2017] [Indexed: 11/22/2022]
Abstract
Insulin stimulates skeletal muscle glucose uptake via activation of the protein kinase B/Akt (Akt) pathway. Recent studies suggest that insulin downregulates AMP-activated protein kinase (AMPK) activity via Ser485/491 phosphorylation of the AMPK α-subunit. Thus lower blood insulin concentrations may induce AMPK signal activation. Acute exercise is one method to stimulate AMPK activation; however, no study has examined the relationship between blood insulin levels and acute resistance exercise-induced AMPK pathway activation. Based on previous findings, we hypothesized that the acute resistance exercise-induced AMPK pathway activation would be augmented by disruptions in insulin secretion through a decrease in AMPKα Ser485/491 inhibitory phosphorylation. To test the hypothesis, 10-wk-old male Sprague-Dawley rats were administered the toxin streptozotocin (STZ; 55 mg/kg) to destroy the insulin secreting β-cells. Three days postinjection, the right gastrocnemius muscle from STZ and control rats was subjected to resistance exercise by percutaneous electrical stimulation. Animals were killed 0, 1, or 3 h later; activation of the Akt/AMPK and downstream pathways in the muscle tissue was analyzed by Western blotting and real-time PCR. Notably, STZ rats showed a significant decrease in basal Akt and AMPKα Ser485/491 phosphorylation, but substantial exercise-induced increases in both AMPKα Thr172 and acetyl-CoA carboxylase (ACC) Ser79 phosphorylation were observed. Although no significant impact on resistance exercise-induced Akt pathway activation or glucose uptake was found, resistance exercise-induced peroxisome proliferator-activated receptor (PPAR)-γ coactivator-1 α (PGC-1α) gene expression was augmented by STZ treatment. Collectively, these data suggest that circulating insulin levels may regulate acute resistance exercise-induced AMPK pathway activation and AMPK-dependent gene expression relating to basal AMPKα Ser485/491 phosphorylation.
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Affiliation(s)
- Kohei Kido
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Takumi Yokokawa
- Laboratory of Sports and Exercise Medicine, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan; and
| | - Satoru Ato
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Koji Sato
- Graduate School of Human Development and Environment, Kobe University, Kobe, Hyogo, Japan
| | - Satoshi Fujita
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Shiga, Japan;
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40
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Love JM, Bober BG, Orozco E, White AT, Bremner SN, Lovering RM, Schenk S, Shah SB. mTOR regulates peripheral nerve response to tensile strain. J Neurophysiol 2017; 117:2075-2084. [PMID: 28250148 PMCID: PMC5434482 DOI: 10.1152/jn.00257.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 02/09/2017] [Accepted: 02/25/2017] [Indexed: 01/26/2023] Open
Abstract
While excessive tensile strain can be detrimental to nerve function, strain can be a positive regulator of neuronal outgrowth. We used an in vivo rat model of sciatic nerve strain to investigate signaling mechanisms underlying peripheral nerve response to deformation. Nerves were deformed by 11% and did not demonstrate deficits in compound action potential latency or amplitude during or after 6 h of strain. As revealed by Western blotting, application of strain resulted in significant upregulation of mammalian target of rapamycin (mTOR) and S6 signaling in nerves, increased myelin basic protein (MBP) and β-actin levels, and increased phosphorylation of neurofilament subunit H (NF-H) compared with unstrained (sham) contralateral nerves (P < 0.05 for all comparisons, paired two-tailed t-test). Strain did not alter neuron-specific β3-tubulin or overall nerve tubulin levels compared with unstrained controls. Systemic rapamycin treatment, thought to selectively target mTOR complex 1 (mTORC1), suppressed mTOR/S6 signaling, reduced levels of MBP and overall tubulin, and decreased NF-H phosphorylation in nerves strained for 6 h, revealing a role for mTOR in increasing MBP expression and NF-H phosphorylation, and maintaining tubulin levels. Consistent with stretch-induced increases in MBP, immunolabeling revealed increased S6 signaling in Schwann cells of stretched nerves compared with unstretched nerves. In addition, application of strain to cultured adult dorsal root ganglion neurons showed an increase in axonal protein synthesis based on a puromycin incorporation assay, suggesting that neuronal translational pathways also respond to strain. This work has important implications for understanding mechanisms underlying nerve response to strain during development and regeneration.NEW & NOTEWORTHY Peripheral nerves experience tensile strain (stretch) during development and movement. Excessive strain impairs neuronal function, but moderate strains are accommodated by nerves and can promote neuronal growth; mechanisms underlying these phenomena are not well understood. We demonstrated that levels of several structural proteins increase following physiological levels of nerve strain and that expression of a subset of these proteins is regulated by mTOR. Our work has important implications for understanding nerve development and strain-based regenerative strategies.
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Affiliation(s)
- James M Love
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - Brian G Bober
- Department of Bioengineering, University of California-San Diego, La Jolla, California
| | - Elisabeth Orozco
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Amanda T White
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California
| | - Shannon N Bremner
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Simon Schenk
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California
| | - Sameer B Shah
- Department of Bioengineering, University of California-San Diego, La Jolla, California; .,Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
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41
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Mirzoev TM, Tyganov SA, Petrova IO, Shenkman BS. The realization of a mechanical signal during gravitational unloading: The response of mTORC1 targets to eccentric contractions. Biophysics (Nagoya-shi) 2016. [DOI: 10.1134/s0006350916050213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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42
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Rindom E, Vissing K. Mechanosensitive Molecular Networks Involved in Transducing Resistance Exercise-Signals into Muscle Protein Accretion. Front Physiol 2016; 7:547. [PMID: 27909410 PMCID: PMC5112233 DOI: 10.3389/fphys.2016.00547] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 10/31/2016] [Indexed: 02/05/2023] Open
Abstract
Loss of skeletal muscle myofibrillar protein with disease and/or inactivity can severely deteriorate muscle strength and function. Strategies to counteract wasting of muscle myofibrillar protein are therefore desirable and invite for considerations on the potential superiority of specific modes of resistance exercise and/or the adequacy of low load resistance exercise regimens as well as underlying mechanisms. In this regard, delineation of the potentially mechanosensitive molecular mechanisms underlying muscle protein synthesis (MPS), may contribute to an understanding on how differentiated resistance exercise can transduce a mechanical signal into stimulation of muscle accretion. Recent findings suggest specific upstream exercise-induced mechano-sensitive myocellular signaling pathways to converge on mammalian target of rapamycin complex 1 (mTORC1), to influence MPS. This may e.g. implicate mechanical activation of signaling through a diacylglycerol kinase (DGKζ)-phosphatidic acid (PA) axis or implicate integrin deformation to signal through a Focal adhesion kinase (FAK)-Tuberous Sclerosis Complex 2 (TSC2)-Ras homolog enriched in brain (Rheb) axis. Moreover, since initiation of translation is reliant on mRNA, it is also relevant to consider potentially mechanosensitive signaling pathways involved in muscle myofibrillar gene transcription and whether some of these pathways converge with those affecting mTORC1 activation for MPS. In this regard, recent findings suggest how mechanical stress may implicate integrin deformation and/or actin dynamics to signal through a Ras homolog gene family member A protein (RhoA)-striated muscle activator of Rho signaling (STARS) axis or implicate deformation of Notch to affect Bone Morphogenetic Protein (BMP) signaling through a small mother of decapentaplegic (Smad) axis.
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Affiliation(s)
- Emil Rindom
- Section of Sport Science, Department of Public Health, Aarhus UniversityAarhus, Denmark; Department of Biomedicine, Aarhus UniversityAarhus, Denmark
| | - Kristian Vissing
- Section of Sport Science, Department of Public Health, Aarhus University Aarhus, Denmark
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43
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Narici M, Franchi M, Maganaris C. Muscle structural assembly and functional consequences. ACTA ACUST UNITED AC 2016; 219:276-84. [PMID: 26792340 DOI: 10.1242/jeb.128017] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The relationship between muscle structure and function has been a matter of investigation since the Renaissance period. Extensive use of anatomical dissections and the introduction of the scientific method enabled early scholars to lay the foundations of muscle physiology and biomechanics. Progression of knowledge in these disciplines led to the current understanding that muscle architecture, together with muscle fibre contractile properties, has a major influence on muscle mechanical properties. Recently, advances in laser diffraction, optical microendoscopy and ultrasonography have enabled in vivo investigations into the behaviour of human muscle fascicles and sarcomeres with varying joint angle and muscle contraction intensity. With these technologies it has become possible to identify the length region over which fascicles and sarcomeres develop maximum isometric force in vivo as well as the operating ranges of fascicles and sarcomeres during real-life activities such as walking. Also, greater insights into the remodelling of muscle architecture in response to overloading and unloading, and in ageing, have been obtained by the use of ultrasonography; these have led to the identification of clinical biomarkers of disuse atrophy and sarcopenia. Recent evidence also shows that the pattern of muscle hypertrophy in response to chronic loading is contraction-mode dependent (eccentric versus concentric), as similar gains in muscle mass, but through differing addition of sarcomeres in series and in parallel (as indirectly inferred from changes in fascicle length and pennation angle), have been found. These innovative observations prompted a new set of investigations into the molecular mechanisms regulating this contraction-specific muscle growth.
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Affiliation(s)
- Marco Narici
- University of Nottingham, Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, Faculty of Medicine and Health Sciences, MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Derby Royal Hospital, Derby DE22 3DT, UK
| | - Martino Franchi
- University of Nottingham, Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, Faculty of Medicine and Health Sciences, MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Derby Royal Hospital, Derby DE22 3DT, UK
| | - Constantinos Maganaris
- Research Institute for Sport and Exercise Sciences, Faculty of Science, Liverpool John Moores University, Liverpool L3 3AF, UK
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44
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Abstract
Hibernation is characterized by prolonged periods of inactivity with concomitantly low nutrient intake, conditions that would typically result in muscle atrophy combined with a loss of oxidative fibers. Yet, hibernators consistently emerge from winter with very little atrophy, frequently accompanied by a slight shift in fiber ratios to more oxidative fiber types. Preservation of muscle morphology is combined with down-regulation of glycolytic pathways and increased reliance on lipid metabolism instead. Furthermore, while rates of protein synthesis are reduced during hibernation, balance is maintained by correspondingly low rates of protein degradation. Proposed mechanisms include a number of signaling pathways and transcription factors that lead to increased oxidative fiber expression, enhanced protein synthesis and reduced protein degradation, ultimately resulting in minimal loss of skeletal muscle protein and oxidative capacity. The functional significance of these outcomes is maintenance of skeletal muscle strength and fatigue resistance, which enables hibernating animals to resume active behaviors such as predator avoidance, foraging and mating immediately following terminal arousal in the spring.
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Affiliation(s)
- Clark J Cotton
- Department of Biology, College of St Benedict/St John's University, Collegeville, MN 56321, USA
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45
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Abstract
The skeletal muscle phenotype is subject to considerable malleability depending on use as well as internal and external cues. In humans, low-load endurance-type exercise leads to qualitative changes of muscle tissue characterized by an increase in structures supporting oxygen delivery and consumption, such as capillaries and mitochondria. High-load strength-type exercise leads to growth of muscle fibers dominated by an increase in contractile proteins. In endurance exercise, stress-induced signaling leads to transcriptional upregulation of genes, with Ca(2+) signaling and the energy status of the muscle cells sensed through AMPK being major input determinants. Several interrelated signaling pathways converge on the transcriptional co-activator PGC-1α, perceived to be the coordinator of much of the transcriptional and post-transcriptional processes. Strength training is dominated by a translational upregulation controlled by mTORC1. mTORC1 is mainly regulated by an insulin- and/or growth-factor-dependent signaling cascade as well as mechanical and nutritional cues. Muscle growth is further supported by DNA recruitment through activation and incorporation of satellite cells. In addition, there are several negative regulators of muscle mass. We currently have a good descriptive understanding of the molecular mechanisms controlling the muscle phenotype. The topology of signaling networks seems highly conserved among species, with the signaling outcome being dependent on the particular way individual species make use of the options offered by the multi-nodal networks. As a consequence, muscle structural and functional modifications can be achieved by an almost unlimited combination of inputs and downstream signaling events.
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Affiliation(s)
- Hans Hoppeler
- Emeritus Department of Anatomy, University of Bern, Baltzerstrasse 2, Bern 9 CH-3000, Switzerland
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46
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Eftestøl E, Egner IM, Lunde IG, Ellefsen S, Andersen T, Sjåland C, Gundersen K, Bruusgaard JC. Increased hypertrophic response with increased mechanical load in skeletal muscles receiving identical activity patterns. Am J Physiol Cell Physiol 2016; 311:C616-C629. [PMID: 27488660 DOI: 10.1152/ajpcell.00016.2016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 07/26/2016] [Indexed: 11/22/2022]
Abstract
It is often assumed that mechanical factors are important for effects of exercise on muscle, but during voluntary training and most experimental conditions the effects could solely be attributed to differences in electrical activity, and direct evidence for a mechanosensory pathway has been scarce. We here show that, in rat muscles stimulated in vivo under deep anesthesia with identical electrical activity patterns, isometric contractions induced twofold more hypertrophy than contractions with 50-60% of the isometric force. The number of myonuclei and the RNA levels of myogenin and myogenic regulatory factor 4 were increased with high load, suggesting that activation of satellite cells is mechano dependent. On the other hand, training induced a major shift in fiber type distribution from type 2b to 2x that was load independent, indicating that the electrical signaling rather than mechanosignaling controls fiber type. RAC-α serine/threonine-protein kinase (Akt) and ribosomal protein S6 kinase β-1 (S6K1) were not significantly differentially activated by load, suggesting that the differences in mechanical factors were not important for activating the Akt/mammalian target of rapamycin/S6K1 pathway. The transmembrane molecule syndecan-4 implied in overload hypertrophy in cardiac muscle was not load dependent, suggesting that mechanosignaling in skeletal muscle is different.
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Affiliation(s)
- Einar Eftestøl
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Ingrid M Egner
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Ida G Lunde
- Department of Genetics, Harvard Medical School, Boston, Massachusetts; Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Stian Ellefsen
- Section for Sport Sciences, Lillehammer University College, Lillehammer, Norway; and
| | - Tom Andersen
- Department of Biosciences, University of Oslo, Oslo, Norway
| | | | | | - Jo C Bruusgaard
- Department of Biosciences, University of Oslo, Oslo, Norway; Department of Health Sciences, Kristiania University College, Oslo, Norway
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Intense Resistance Exercise Promotes the Acute and Transient Nuclear Translocation of Small Ubiquitin-Related Modifier (SUMO)-1 in Human Myofibres. Int J Mol Sci 2016; 17:ijms17050646. [PMID: 27136539 PMCID: PMC4881472 DOI: 10.3390/ijms17050646] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 04/15/2016] [Accepted: 04/21/2016] [Indexed: 01/14/2023] Open
Abstract
Protein sumoylation is a posttranslational modification triggered by cellular stress. Because general information concerning the role of small ubiquitin-related modifier (SUMO) proteins in adult skeletal muscle is sparse, we investigated whether SUMO-1 proteins will be subjected to time-dependent changes in their subcellular localization in sarcoplasmic and nuclear compartments of human type I and II skeletal muscle fibers in response to acute stimulation by resistance exercise (RE). Skeletal muscle biopsies were taken at baseline (PRE), 15, 30, 60, 240 min and 24 h post RE from 6 male subjects subjected to a single bout of one-legged knee extensions. SUMO-1 localization was determined via immunohistochemistry and confocal laser microscopy. At baseline SUMO-1 was localized in perinuclear regions of myonuclei. Within 15 and up to 60 min post exercise, nuclear SUMO-1 localization was significantly increased (p < 0.01), declining towards baseline levels within 240 min post exercise. Sarcoplasmic SUMO-1 localization was increased at 15 min post exercise in type I and up to 30 min post RE in type II myofibres. The changing localization of SUMO-1 proteins acutely after intense muscle contractions points to a role for SUMO proteins in the acute regulation of the skeletal muscle proteome after exercise.
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Röhling M, Herder C, Stemper T, Müssig K. Influence of Acute and Chronic Exercise on Glucose Uptake. J Diabetes Res 2016; 2016:2868652. [PMID: 27069930 PMCID: PMC4812462 DOI: 10.1155/2016/2868652] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 01/31/2016] [Accepted: 02/03/2016] [Indexed: 02/06/2023] Open
Abstract
Insulin resistance plays a key role in the development of type 2 diabetes. It arises from a combination of genetic predisposition and environmental and lifestyle factors including lack of physical exercise and poor nutrition habits. The increased risk of type 2 diabetes is molecularly based on defects in insulin signaling, insulin secretion, and inflammation. The present review aims to give an overview on the molecular mechanisms underlying the uptake of glucose and related signaling pathways after acute and chronic exercise. Physical exercise, as crucial part in the prevention and treatment of diabetes, has marked acute and chronic effects on glucose disposal and related inflammatory signaling pathways. Exercise can stimulate molecular signaling pathways leading to glucose transport into the cell. Furthermore, physical exercise has the potential to modulate inflammatory processes by affecting specific inflammatory signaling pathways which can interfere with signaling pathways of the glucose uptake. The intensity of physical training appears to be the primary determinant of the degree of metabolic improvement modulating the molecular signaling pathways in a dose-response pattern, whereas training modality seems to have a secondary role.
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Affiliation(s)
- Martin Röhling
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Munich, 85764 Neuherberg, Germany
| | - Christian Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Munich, 85764 Neuherberg, Germany
| | - Theodor Stemper
- Department Fitness and Health, University Wuppertal, 42119 Wuppertal, Germany
| | - Karsten Müssig
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Munich, 85764 Neuherberg, Germany
- Department of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
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Garatachea N, Pareja-Galeano H, Sanchis-Gomar F, Santos-Lozano A, Fiuza-Luces C, Morán M, Emanuele E, Joyner MJ, Lucia A. Exercise attenuates the major hallmarks of aging. Rejuvenation Res 2016; 18:57-89. [PMID: 25431878 DOI: 10.1089/rej.2014.1623] [Citation(s) in RCA: 242] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Regular exercise has multi-system anti-aging effects. Here we summarize how exercise impacts the major hallmarks of aging. We propose that, besides searching for novel pharmaceutical targets of the aging process, more research efforts should be devoted to gaining insights into the molecular mediators of the benefits of exercise and to implement effective exercise interventions for elderly people.
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Affiliation(s)
- Nuria Garatachea
- 1 Faculty of Health and Sport Science, University of Zaragoza , Huesca, Spain
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Brook MS, Wilkinson DJ, Phillips BE, Perez-Schindler J, Philp A, Smith K, Atherton PJ. Skeletal muscle homeostasis and plasticity in youth and ageing: impact of nutrition and exercise. Acta Physiol (Oxf) 2016; 216:15-41. [PMID: 26010896 PMCID: PMC4843955 DOI: 10.1111/apha.12532] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 11/10/2014] [Accepted: 05/18/2015] [Indexed: 12/18/2022]
Abstract
Skeletal muscles comprise a substantial portion of whole body mass and are integral for locomotion and metabolic health. Increasing age is associated with declines in both muscle mass and function (e.g. strength‐related performance, power) with declines in muscle function quantitatively outweighing those in muscle volume. The mechanisms behind these declines are multi‐faceted involving both intrinsic age‐related metabolic dysregulation and environmental influences such as nutritional and physical activity. Ageing is associated with a degree of ‘anabolic resistance’ to these key environmental inputs, which likely accelerates the intrinsic processes driving ageing. On this basis, strategies to sensitize and/or promote anabolic responses to nutrition and physical activity are likely to be imperative in alleviating the progression and trajectory of sarcopenia. Both resistance‐ and aerobic‐type exercises are likely to confer functional and health benefits in older age, and a clutch of research suggests that enhancement of anabolic responsiveness to exercise and/or nutrition may be achieved by optimizing modifications of muscle‐loading paradigms (workload, volume, blood flow restriction) or nutritional support (e.g. essential amino acid/leucine) patterns. Nonetheless, more work is needed in which a more holistic view in ageing studies is taken into account. This should include improved characterization of older study recruits, that is physical activity/nutritional behaviours, to limit confounding variables influencing whether findings are attributable to age, or other environmental influences. Nonetheless, on balance, ageing is associated with declines in muscle mass and function and a partially related decline in aerobic capacity. There is also good evidence that metabolic flexibility is impaired in older age.
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Affiliation(s)
- M. S. Brook
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical Metabolic and Molecular Physiology; University of Nottingham; Royal Derby Hospital Centre; Derby UK
| | - D. J. Wilkinson
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical Metabolic and Molecular Physiology; University of Nottingham; Royal Derby Hospital Centre; Derby UK
| | - B. E. Phillips
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical Metabolic and Molecular Physiology; University of Nottingham; Royal Derby Hospital Centre; Derby UK
| | - J. Perez-Schindler
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, School of Sport, Exercise and Rehabilitation Sciences; University of Birmingham; Birmingham UK
| | - A. Philp
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, School of Sport, Exercise and Rehabilitation Sciences; University of Birmingham; Birmingham UK
| | - K. Smith
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical Metabolic and Molecular Physiology; University of Nottingham; Royal Derby Hospital Centre; Derby UK
| | - P. J. Atherton
- MRC-ARUK Centre of Excellence for Musculoskeletal Ageing Research, Clinical Metabolic and Molecular Physiology; University of Nottingham; Royal Derby Hospital Centre; Derby UK
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