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Smith GR, Zhao B, Lindholm ME, Raja A, Viggars M, Pincas H, Gay NR, Sun Y, Ge Y, Nair VD, Sanford JA, Amper MAS, Vasoya M, Smith KS, Montgomery S, Zaslavsky E, Bodine SC, Esser KA, Walsh MJ, Snyder MP. Multi-omic identification of key transcriptional regulatory programs during endurance exercise training. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.10.523450. [PMID: 36711841 PMCID: PMC9882056 DOI: 10.1101/2023.01.10.523450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Transcription factors (TFs) play a key role in regulating gene expression and responses to stimuli. We conducted an integrated analysis of chromatin accessibility, DNA methylation, and RNA expression across eight rat tissues following endurance exercise training (EET) to map epigenomic changes to transcriptional changes and determine key TFs involved. We uncovered tissue-specific changes and TF motif enrichment across all omic layers, differentially accessible regions (DARs), differentially methylated regions (DMRs), and differentially expressed genes (DEGs). We discovered distinct routes of EET-induced regulation through either epigenomic alterations providing better access for TFs to affect target genes, or via changes in TF expression or activity enabling target gene response. We identified TF motifs enriched among correlated epigenomic and transcriptomic alterations, DEGs correlated with exercise-related phenotypic changes, and EET-induced activity changes of TFs enriched for DEGs among their gene targets. This analysis elucidates the unique transcriptional regulatory mechanisms mediating diverse organ effects of EET.
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Affiliation(s)
- Gregory R Smith
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- These authors contributed equally
| | - Bingqing Zhao
- Department of Genetics, Stanford University, Stanford, CA 94305
- These authors contributed equally
| | - Malene E Lindholm
- Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305
| | - Archana Raja
- Division of Cardiovascular Medicine, Stanford University, Stanford, CA 94305
| | - Mark Viggars
- Department of Physiology and Aging, University of Florida, Gainesville, Florida 32610
| | - Hanna Pincas
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Nicole R Gay
- Department of Genetics, Stanford University, Stanford, CA 94305
| | - Yifei Sun
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Yongchao Ge
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Venugopalan D Nair
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - James A Sanford
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Mary Anne S Amper
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Mital Vasoya
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Kevin S Smith
- Department of Genetics, Stanford University, Stanford, CA 94305
- Department of Pathology, Stanford University, Stanford, CA 94305
| | - Stephen Montgomery
- Department of Genetics, Stanford University, Stanford, CA 94305
- Department of Pathology, Stanford University, Stanford, CA 94305
| | - Elena Zaslavsky
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Sue C Bodine
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Karyn A Esser
- Department of Physiology and Aging, University of Florida, Gainesville, Florida 32610
| | - Martin J Walsh
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
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Yang G, Dong Q, Yang H, Wang F, Chen L, Tang J, Huang G, Zhao Y. Changes Observed in Potential Key Candidate Genes of Peripheral Immunity Induced by Tai Chi among Patients with Parkinson's Disease. Genes (Basel) 2022; 13:genes13101863. [PMID: 36292747 PMCID: PMC9601924 DOI: 10.3390/genes13101863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 11/04/2022] Open
Abstract
Parkinson’s disease (PD) is a common progressive neurodegenerative disease characterized by motor dysfunction. Although the inhibition of inflammation by Tai Chi has been demonstrated to involve a peripheral cytokine response and may play an important role in improving the motor function of PD patients, the related specific molecular mechanisms of the peripheral immune response to Tai Chi are not fully understood. The microarray dataset ‘GSE124676’ for the peripheral immune response to Tai Chi of PD patients was downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were screened and analyzed using weighted gene co-expression network analysis (WGCNA). A total of 136 DEGs were found in the PD patients after Tai Chi, suggesting an effect of Tai Chi on the peripheral immunity of PD patients. The DEGs are mainly involved in neutrophil activation, T-cell activation, and NOD-like receptor and IL-17 signaling pathways. Furthermore, six key candidate genes (FOS, FOSB, JUNB, ZFP36, CAMP and LCN2) that are involved in peripheral inflammation and the inhibition of inflammation induced by Tai Chi were observed. The results in the present study could be conducive to comprehensively understanding the molecular mechanism involved in the effect of Tai Chi on peripheral inflammation in PD patients and providing novel targets for future advanced research.
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Affiliation(s)
- Guang Yang
- Physical Education Department, Shanghai Jiao Tong University, Shanghai 200042, China
| | - Qun Dong
- Department of Bioinformatics and Biostatistics, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Huixin Yang
- Institute of Nation Traditional Sports, Harbin Sport University, Harbin 150006, China
| | - Fan Wang
- Institute of Nation Traditional Sports, Harbin Sport University, Harbin 150006, China
| | - Linwei Chen
- Institute of Nation Traditional Sports, Harbin Sport University, Harbin 150006, China
| | - Junze Tang
- Institute of Nation Traditional Sports, Harbin Sport University, Harbin 150006, China
| | - Guoyuan Huang
- Pott College of Science, Engineering and Education, University of Southern Indiana, Indiana, IN 47712, USA
- Correspondence: (G.H.); (Y.Z.)
| | - Ying Zhao
- Physical Education Department, Shanghai Jiao Tong University, Shanghai 200042, China
- Correspondence: (G.H.); (Y.Z.)
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Hinkle ER, Blue RE, Tsai YH, Combs M, Davi J, Coffey AR, Boriek AM, Taylor JM, Parker JS, Giudice J. Stretching muscle cells induces transcriptional and splicing transitions and changes in SR proteins. Commun Biol 2022; 5:987. [PMID: 36123433 PMCID: PMC9485123 DOI: 10.1038/s42003-022-03915-7] [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: 04/14/2022] [Accepted: 08/30/2022] [Indexed: 11/08/2022] Open
Abstract
Alternative splicing is an RNA processing mechanism involved in skeletal muscle development and pathology. Muscular diseases exhibit splicing alterations and changes in mechanobiology leading us to investigate the interconnection between mechanical forces and RNA processing. We performed deep RNA-sequencing after stretching muscle cells. First, we uncovered transcriptional changes in genes encoding proteins involved in muscle function and transcription. Second, we observed that numerous mechanosensitive genes were part of the MAPK pathway which was activated in response to stretching. Third, we revealed that stretching skeletal muscle cells increased the proportion of alternatively spliced cassette exons and their inclusion. Fourth, we demonstrated that the serine and arginine-rich proteins exhibited stronger transcriptional changes than other RNA-binding proteins and that SRSF4 phosphorylation is mechanosensitive. Identifying SRSF4 as a mechanosensitive RNA-binding protein that might contribute to crosstalk between mechanotransduction, transcription, and splicing could potentially reveal novel insights into muscular diseases, particularly those with unknown etiologies.
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Affiliation(s)
- Emma R Hinkle
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - R Eric Blue
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Yi-Hsuan Tsai
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Matthew Combs
- Department of Pathology and Laboratory Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Jacquelyn Davi
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Alisha R Coffey
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Aladin M Boriek
- Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Joan M Taylor
- Department of Pathology and Laboratory Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
- McAllister Heart Institute, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Joel S Parker
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
- Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA
| | - Jimena Giudice
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA.
- Curriculum in Genetics and Molecular Biology (GMB), The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA.
- McAllister Heart Institute, The University of North Carolina at Chapel Hill, Chapel Hill, 27599, NC, USA.
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FGF-2-dependent signaling activated in aged human skeletal muscle promotes intramuscular adipogenesis. Proc Natl Acad Sci U S A 2021; 118:2021013118. [PMID: 34493647 PMCID: PMC8449320 DOI: 10.1073/pnas.2021013118] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 06/23/2021] [Indexed: 01/07/2023] Open
Abstract
Aged skeletal muscle is markedly affected by fatty muscle infiltration, and strategies to reduce the occurrence of intramuscular adipocytes are urgently needed. Here, we show that fibroblast growth factor-2 (FGF-2) not only stimulates muscle growth but also promotes intramuscular adipogenesis. Using multiple screening assays upstream and downstream of microRNA (miR)-29a signaling, we located the secreted protein and adipogenic inhibitor SPARC to an FGF-2 signaling pathway that is conserved between skeletal muscle cells from mice and humans and that is activated in skeletal muscle of aged mice and humans. FGF-2 induces the miR-29a/SPARC axis through transcriptional activation of FRA-1, which binds and activates an evolutionary conserved AP-1 site element proximal in the miR-29a promoter. Genetic deletions in muscle cells and adeno-associated virus-mediated overexpression of FGF-2 or SPARC in mouse skeletal muscle revealed that this axis regulates differentiation of fibro/adipogenic progenitors in vitro and intramuscular adipose tissue (IMAT) formation in vivo. Skeletal muscle from human donors aged >75 y versus <55 y showed activation of FGF-2-dependent signaling and increased IMAT. Thus, our data highlights a disparate role of FGF-2 in adult skeletal muscle and reveals a pathway to combat fat accumulation in aged human skeletal muscle.
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Cahill T, Cope H, Bass JJ, Overbey EG, Gilbert R, da Silveira WA, Paul AM, Mishra T, Herranz R, Reinsch SS, Costes SV, Hardiman G, Szewczyk NJ, Tahimic CGT. Mammalian and Invertebrate Models as Complementary Tools for Gaining Mechanistic Insight on Muscle Responses to Spaceflight. Int J Mol Sci 2021; 22:ijms22179470. [PMID: 34502375 PMCID: PMC8430797 DOI: 10.3390/ijms22179470] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/22/2021] [Accepted: 08/23/2021] [Indexed: 02/07/2023] Open
Abstract
Bioinformatics approaches have proven useful in understanding biological responses to spaceflight. Spaceflight experiments remain resource intensive and rare. One outstanding issue is how to maximize scientific output from a limited number of omics datasets from traditional animal models including nematodes, fruitfly, and rodents. The utility of omics data from invertebrate models in anticipating mammalian responses to spaceflight has not been fully explored. Hence, we performed comparative analyses of transcriptomes of soleus and extensor digitorum longus (EDL) in mice that underwent 37 days of spaceflight. Results indicate shared stress responses and altered circadian rhythm. EDL showed more robust growth signals and Pde2a downregulation, possibly underlying its resistance to atrophy versus soleus. Spaceflight and hindlimb unloading mice shared differential regulation of proliferation, circadian, and neuronal signaling. Shared gene regulation in muscles of humans on bedrest and space flown rodents suggest targets for mitigating muscle atrophy in space and on Earth. Spaceflight responses of C. elegans were more similar to EDL. Discrete life stages of D. melanogaster have distinct utility in anticipating EDL and soleus responses. In summary, spaceflight leads to shared and discrete molecular responses between muscle types and invertebrate models may augment mechanistic knowledge gained from rodent spaceflight and ground-based studies.
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Affiliation(s)
- Thomas Cahill
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (G.H.)
| | - Henry Cope
- Nottingham Biomedical Research Centre (BRC), School of Computer Science, University of Nottingham, Nottingham NG7 2QL, UK;
| | - Joseph J. Bass
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute for Health Research (NIHR), Nottingham Biomedical Research Centre (BRC), University of Nottingham, Nottingham NG7 2QL, UK; (J.J.B.); (N.J.S.)
| | - Eliah G. Overbey
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA;
| | - Rachel Gilbert
- NASA Ames Research Center, Space Biosciences Division, Moffett Field, CA 94035, USA; (R.G.); (A.M.P.); (S.S.R.); (S.V.C.)
- Universities Space Research Association, Columbia, MD 21046, USA
| | - Willian Abraham da Silveira
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (G.H.)
- Department of Biological Sciences, School of Life Sciences and Education, Staffordshire University, Stoke-on-Trent ST4 2DF, UK
| | - Amber M. Paul
- NASA Ames Research Center, Space Biosciences Division, Moffett Field, CA 94035, USA; (R.G.); (A.M.P.); (S.S.R.); (S.V.C.)
- Department of Human Factors and Behavioral Neurobiology, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114, USA
- Blue Marble Space Institute of Science, Seattle, WA 98104, USA
| | - Tejaswini Mishra
- Department of Genetics, Stanford University School of Medicine, Palo Alto, CA 94305, USA;
| | - Raúl Herranz
- Centro de Investigaciones Biológicas Margarita Salas–CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain;
| | - Sigrid S. Reinsch
- NASA Ames Research Center, Space Biosciences Division, Moffett Field, CA 94035, USA; (R.G.); (A.M.P.); (S.S.R.); (S.V.C.)
| | - Sylvain V. Costes
- NASA Ames Research Center, Space Biosciences Division, Moffett Field, CA 94035, USA; (R.G.); (A.M.P.); (S.S.R.); (S.V.C.)
| | - Gary Hardiman
- School of Biological Sciences & Institute for Global Food Security, Queens University Belfast, Belfast BT9 5DL, UK; (T.C.); (W.A.d.S.); (G.H.)
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Nathaniel J. Szewczyk
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute for Health Research (NIHR), Nottingham Biomedical Research Centre (BRC), University of Nottingham, Nottingham NG7 2QL, UK; (J.J.B.); (N.J.S.)
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Candice G. T. Tahimic
- NASA Ames Research Center, Space Biosciences Division, Moffett Field, CA 94035, USA; (R.G.); (A.M.P.); (S.S.R.); (S.V.C.)
- Department of Biology, University of North Florida, Jacksonville, FL 32224, USA
- Correspondence:
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Jacques M, Landen S, Alvarez Romero J, Yan X, Garnham A, Hiam D, Siegwald M, Mercier E, Hecksteden A, Eynon N, Voisin S. Individual physiological and mitochondrial responses during 12 weeks of intensified exercise. Physiol Rep 2021; 9:e14962. [PMID: 34327858 PMCID: PMC8322753 DOI: 10.14814/phy2.14962] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 12/02/2022] Open
Abstract
AIM Observed effects of exercise are highly variable between individuals, and subject-by-training interaction (i.e., individual response variability) is often not estimated. Here, we measured mitochondrial (citrate synthetase, cytochrome-c oxidase, succinate dehydrogenase, and mitochondrial copy-number), performance markers (Wpeak , lactate threshold [LT], and VO2peak ), and fiber type proportions/expression (type I, type IIa, and type IIx) in multiple time points during 12-week of high-intensity interval training (HIIT) to investigate effects of exercise at the individual level. METHODS Sixteen young (age: 33.1 ± 9.0 years), healthy men (VO2peak 35-60 ml/min/kg and BMI: 26.4 ± 4.2) from the Gene SMART study completed 12-week of progressive HIIT. Performance markers and muscle biopsies were collected every 4 weeks. We used mixed-models and bivariate growth models to quantify individual response and to estimate correlations between variables. RESULTS All performance markers exhibited significant (Wpeak 0.56 ± 0.33 p = 0.003, LT 0.37 ± 0.35 p = 0.007, VO2peak 3.81 ± 6.13 p = 0.02) increases overtime, with subject-by-training interaction being present (95% CI: Wpeak 0.09-0.24, LT 0.06-0.18, VO2peak 0.27-2.32). All other measurements did not exhibit significant changes. Fiber type IIa proportions at baseline was significantly associated with all physiological variables (p < 0.05), and citrate synthetase and cytochrome-c oxidase levels at baseline and overtime (i.e., intercept and slope) presented significant covariance (p < 0.05). Finally, low correlations between performance and mitochondrial markers were observed. CONCLUSION We identified a significant subject-by-training interaction for the performance markers. While for all other measures within-subject variability was too large and interindividual differences in training efficacy could not be verified. Changes in measurements in response to exercise were not correlated, and such disconnection should be further investigated by future studies.
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Affiliation(s)
- Macsue Jacques
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | - Shanie Landen
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | | | - Xu Yan
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
- Australian Institute for Musculoskeletal Science (AIMSS)MelbourneAustralia
| | - Andrew Garnham
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | - Danielle Hiam
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
| | | | | | - Anne Hecksteden
- Institute of Sports and Preventive MedicineSaarland UniversitySaarbrückenGermany
| | - Nir Eynon
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
- Murdoch Children’s Research InstituteMelbourneAustralia
| | - Sarah Voisin
- Institute for Health and Sport (iHeS)Victoria UniversityMelbourneAustralia
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Hagan ML, Balayan V, McGee-Lawrence ME. Plasma membrane disruption (PMD) formation and repair in mechanosensitive tissues. Bone 2021; 149:115970. [PMID: 33892174 PMCID: PMC8217198 DOI: 10.1016/j.bone.2021.115970] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/26/2021] [Accepted: 04/17/2021] [Indexed: 01/04/2023]
Abstract
Mammalian cells employ an array of biological mechanisms to detect and respond to mechanical loading in their environment. One such mechanism is the formation of plasma membrane disruptions (PMD), which foster a molecular flux across cell membranes that promotes tissue adaptation. Repair of PMD through an orchestrated activity of molecular machinery is critical for cell survival, and the rate of PMD repair can affect downstream cellular signaling. PMD have been observed to influence the mechanical behavior of skin, alveolar, and gut epithelial cells, aortic endothelial cells, corneal keratocytes and epithelial cells, cardiac and skeletal muscle myocytes, neurons, and most recently, bone cells including osteoblasts, periodontal ligament cells, and osteocytes. PMD are therefore positioned to affect the physiological behavior of a wide range of vertebrate organ systems including skeletal and cardiac muscle, skin, eyes, the gastrointestinal tract, the vasculature, the respiratory system, and the skeleton. The purpose of this review is to describe the processes of PMD formation and repair across these mechanosensitive tissues, with a particular emphasis on comparing and contrasting repair mechanisms and downstream signaling to better understand the role of PMD in skeletal mechanobiology. The implications of PMD-related mechanisms for disease and potential therapeutic applications are also explored.
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Affiliation(s)
- Mackenzie L Hagan
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., CB1101, Augusta, GA, USA
| | - Vanshika Balayan
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., CB1101, Augusta, GA, USA
| | - Meghan E McGee-Lawrence
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., CB1101, Augusta, GA, USA; Department of Orthopaedic Surgery, Augusta University, Augusta, GA, USA.
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Al-Attar R, Storey KB. Suspended in time: Molecular responses to hibernation also promote longevity. Exp Gerontol 2020; 134:110889. [PMID: 32114078 DOI: 10.1016/j.exger.2020.110889] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 12/16/2022]
Abstract
Aging in most animals is an inevitable process that causes or is a result of physiological, biochemical, and molecular changes in the body, and has a strong influence on an organism's lifespan. Although advancement in medicine has allowed humans to live longer, the prevalence of age-associated medical complications is continuously burdening older adults worldwide. Current animal models used in research to study aging have provided novel information that has helped investigators understand the aging process; however, these models are limiting. Aging is a complex process that is regulated at multiple biological levels, and while a single manipulation in these models can provide information on a process, it is not enough to understand the global regulation of aging. Some mammalian hibernators live up to 9.8-times higher than their expected average lifespan, and new research attributes this increase to their ability to hibernate. A common theme amongst these mammalian hibernators is their ability to greatly reduce their metabolic rate to a fraction of their normal rate and initiate cytoprotective responses that enable their survival. Metabolic rate depression is strictly regulated at different biological levels in order to enable the animal to not only survive, but to also do so by relying mainly on their limited internal fuels. As such, understanding both the global and specific regulatory mechanisms used to promote survival during hibernation could, in theory, allow investigators to have a better understanding of the aging process. This can also allow pharmaceutical industries to find therapeutics that could delay or reverse age-associated medical complications and promote healthy aging and longevity in humans.
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Affiliation(s)
- Rasha Al-Attar
- Institute of Biochemistry and Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
| | - Kenneth B Storey
- Institute of Biochemistry and Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
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Comparative Transcriptome and Methylome Analysis in Human Skeletal Muscle Anabolism, Hypertrophy and Epigenetic Memory. Sci Rep 2019; 9:4251. [PMID: 30862794 PMCID: PMC6414679 DOI: 10.1038/s41598-019-40787-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 02/22/2019] [Indexed: 02/07/2023] Open
Abstract
Transcriptome wide changes in human skeletal muscle after acute (anabolic) and chronic resistance exercise (RE) induced hypertrophy have been extensively determined in the literature. We have also recently undertaken DNA methylome analysis (850,000 + CpG sites) in human skeletal muscle after acute and chronic RE, detraining and retraining, where we identified an association between DNA methylation and epigenetic memory of exercise induced skeletal muscle hypertrophy. However, it is currently unknown as to whether all the genes identified in the transcriptome studies to date are also epigenetically regulated at the DNA level after acute, chronic or repeated RE exposure. We therefore aimed to undertake large scale bioinformatical analysis by pooling the publicly available transcriptome data after acute (110 samples) and chronic RE (181 samples) and comparing these large data sets with our genome-wide DNA methylation analysis in human skeletal muscle after acute and chronic RE, detraining and retraining. Indeed, after acute RE we identified 866 up- and 936 down-regulated genes at the expression level, with 270 (out of the 866 up-regulated) identified as being hypomethylated, and 216 (out of 936 downregulated) as hypermethylated. After chronic RE we identified 2,018 up- and 430 down-regulated genes with 592 (out of 2,018 upregulated) identified as being hypomethylated and 98 (out of 430 genes downregulated) as hypermethylated. After KEGG pathway analysis, genes associated with ‘cancer’ pathways were significantly enriched in both bioinformatic analysis of the pooled transcriptome and methylome datasets after both acute and chronic RE. This resulted in 23 (out of 69) and 28 (out of 49) upregulated and hypomethylated and 12 (out of 37) and 2 (out of 4) downregulated and hypermethylated ‘cancer’ genes following acute and chronic RE respectively. Within skeletal muscle tissue, these ‘cancer’ genes predominant functions were associated with matrix/actin structure and remodelling, mechano-transduction (e.g. PTK2/Focal Adhesion Kinase and Phospholipase D- following chronic RE), TGF-beta signalling and protein synthesis (e.g. GSK3B after acute RE). Interestingly, 51 genes were also identified to be up/downregulated in both the acute and chronic RE pooled transcriptome analysis as well as significantly hypo/hypermethylated after acute RE, chronic RE, detraining and retraining. Five genes; FLNB, MYH9, SRGAP1, SRGN, ZMIZ1 demonstrated increased gene expression in the acute and chronic RE transcriptome and also demonstrated hypomethylation in these conditions. Importantly, these 5 genes demonstrated retained hypomethylation even during detraining (following training induced hypertrophy) when exercise was ceased and lean mass returned to baseline (pre-training) levels, identifying them as genes associated with epigenetic memory in skeletal muscle. Importantly, for the first time across the transcriptome and epigenome combined, this study identifies novel differentially methylated genes associated with human skeletal muscle anabolism, hypertrophy and epigenetic memory.
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Islam H, Edgett BA, Bonafiglia JT, Shulman T, Ma A, Quadrilatero J, Simpson CA, Gurd BJ. Repeatability of exercise-induced changes in mRNA expression and technical considerations for qPCR analysis in human skeletal muscle. Exp Physiol 2019; 104:407-420. [PMID: 30657617 DOI: 10.1113/ep087401] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/08/2019] [Indexed: 01/20/2023]
Abstract
NEW FINDINGS What is the central question of this study? Are individual changes in exercise-induced mRNA expression repeatable (i.e. representative of the true response to exercise rather than random error)? What is the main finding and its importance? Exercise-induced changes in mRNA expression are not repeatable even under identical experimental conditions, thereby challenging the use of mRNA expression as a biomarker of adaptive potential and/or individual responsiveness to exercise. ABSTRACT It remains unknown if (1) the observed change in mRNA expression reflects an individual's true response to exercise or random (technical and/or biological) error, and (2) the individual responsiveness to exercise is protocol-specific. We examined the repeatability of skeletal muscle PGC-1α, PDK4, NRF-1, VEGF-A, HSP72 and p53 mRNA expression following two identical endurance exercise (END) bouts (END-1, END-2; 30 min of cycling at 65% of peak work rate (WRpeak ), n = 11) and inter-individual variability in PGC-1α and PDK4 mRNA expression following END and sprint interval training (SIT; 8 × 20 s cycling intervals at ∼170% WRpeak , n = 10) in active young males. The repeatability of key gene analysis steps (RNA extraction, reverse transcription, qPCR) and within-sample fibre-type distribution (n = 8) was also determined to examine potential sources of technical error in our analyses. Despite highly repeatable exercise bout characteristics (work rate, heart rate, blood lactate; ICC > 0.71; CV < 10%; r > 0.85, P < 0.01), gene analysis steps (ICC > 0.73; CV < 24%; r > 0.75, P < 0.01), and similar group-level changes in mRNA expression, individual changes in PGC-1α, PDK4, VEGF-A and p53 mRNA expression were not repeatable (ICC < 0.22; CV > 20%; r < 0.21). Fibre-type distribution in two portions of the same muscle biopsy was highly variable and not significantly related (ICC = 0.39; CV = 26%; r = 0.37, P = 0.37). Since individual changes in mRNA expression following identical exercise bouts were not repeatable, inferences regarding individual responsiveness to END or SIT were not made. Substantial random error exists in changes in mRNA expression following acute exercise, thereby challenging the use of mRNA expression for analysing individual responsiveness to exercise.
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Affiliation(s)
- Hashim Islam
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Brittany A Edgett
- IMPART Team Canada Investigator Network, Saint John, New Brunswick, Canada.,Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada.,Department of Pharmacology, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada
| | - Jacob T Bonafiglia
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Talya Shulman
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Andrew Ma
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Joe Quadrilatero
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Craig A Simpson
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Brendon J Gurd
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
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Berdeaux R, Hutchins C. Anabolic and Pro-metabolic Functions of CREB-CRTC in Skeletal Muscle: Advantages and Obstacles for Type 2 Diabetes and Cancer Cachexia. Front Endocrinol (Lausanne) 2019; 10:535. [PMID: 31428057 PMCID: PMC6688074 DOI: 10.3389/fendo.2019.00535] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/18/2019] [Indexed: 12/31/2022] Open
Abstract
cAMP is one of the earliest described mediators of hormone action in response to physiologic stress that allows acute stress responses and adaptation in every tissue. The classic role of cAMP signaling in metabolic tissues is to regulate nutrient partitioning. In response to acute stress, such as epinephrine released during strenuous exercise or fasting, intramuscular cAMP liberates glucose from glycogen and fatty acids from triglycerides. In the long-term, activation of Gs-coupled GPCRs stimulates muscle growth (hypertrophy) and metabolic adaptation through multiple pathways that culminate in a net increase of protein synthesis, mitochondrial biogenesis, and improved metabolic efficiency. This review focuses on regulation, function, and transcriptional targets of CREB (cAMP response element binding protein) and CRTCs (CREB regulated transcriptional coactivators) in skeletal muscle and the potential for targeting this pathway to sustain muscle mass and metabolic function in type 2 diabetes and cancer. Although the muscle-autonomous roles of these proteins might render them excellent targets for both conditions, pharmacologic targeting must be approached with caution. Gain of CREB-CRTC function is associated with excess liver glucose output in type 2 diabetes, and growing evidence implicates CREB-CRTC activation in proliferation and invasion of different types of cancer cells. We conclude that deeper investigation to identify skeletal muscle specific regulatory mechanisms that govern CREB-CRTC transcriptional activity is needed to safely take advantage of their potent effects to invigorate skeletal muscle to potentially improve health in people with type 2 diabetes and cancer.
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Affiliation(s)
- Rebecca Berdeaux
- Department of Integrative Biology and Pharmacology, Center for Metabolic and Degenerative Diseases, The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center Houston, Houston, TX, United States
- Graduate Program in Biochemistry and Cell Biology, The MD Anderson-UTHealth Graduate School of Biomedical Sciences, Houston, TX, United States
- *Correspondence: Rebecca Berdeaux
| | - Chase Hutchins
- Department of Integrative Biology and Pharmacology, Center for Metabolic and Degenerative Diseases, The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center Houston, Houston, TX, United States
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12
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Kokosar M, Benrick A, Perfilyev A, Nilsson E, Källman T, Ohlsson C, Ling C, Stener-Victorin E. A Single Bout of Electroacupuncture Remodels Epigenetic and Transcriptional Changes in Adipose Tissue in Polycystic Ovary Syndrome. Sci Rep 2018; 8:1878. [PMID: 29382850 PMCID: PMC5790004 DOI: 10.1038/s41598-017-17919-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/04/2017] [Indexed: 12/13/2022] Open
Abstract
A single bout of electroacupuncture results in muscle contractions and increased whole body glucose uptake in women with polycystic ovary syndrome (PCOS). Women with PCOS have transcriptional and epigenetic alterations in the adipose tissue and we hypothesized that electroacupuncture induces epigenetic and transcriptional changes to restore metabolic alterations. Twenty-one women with PCOS received a single bout of electroacupuncture, which increased the whole body glucose uptake. In subcutaneous adipose tissue biopsies, we identified treatment-induced expression changes of 2369 genes (Q < 0.05) and DNA methylation changes of 7055 individual genes (Q = 0.11). The largest increase in expression was observed for FOSB (2405%), and the largest decrease for LOC100128899 (54%). The most enriched pathways included Acute phase response signaling and LXR/RXR activation. The DNA methylation changes ranged from 1-16%, and 407 methylation sites correlated with gene expression. Among genes known to be differentially expressed in PCOS, electroacupuncture reversed the expression of 80 genes, including PPARγ and ADIPOR2. Changes in the expression of Nr4a2 and Junb are reversed by adrenergic blockers in rats demonstrating that changes in gene expression, in part, is due to activation of the sympathetic nervous system. In conclusion, low-frequency electroacupuncture with muscle contractions remodels epigenetic and transcriptional changes that elicit metabolic improvement.
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Affiliation(s)
- Milana Kokosar
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anna Benrick
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- School of Health and Education, University of Skövde, Skövde, Sweden
| | - Alexander Perfilyev
- Epigenetics and Diabetes, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Clinical Research Centre, Scania University Hospital, Malmö, Sweden
| | - Emma Nilsson
- Epigenetics and Diabetes, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Clinical Research Centre, Scania University Hospital, Malmö, Sweden
| | - Thomas Källman
- Department of Medical Biochemistry and Microbiology, NBIS - National Bioinformatics Infrastructure Sweden, SciLifeLab, Uppsala University, Uppsala, Sweden
| | - Claes Ohlsson
- Centre for Bone and Arthritis Research, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Charlotte Ling
- Epigenetics and Diabetes, Department of Clinical Sciences, Lund University Diabetes Centre, Lund University, Clinical Research Centre, Scania University Hospital, Malmö, Sweden
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Tessier SN, Zhang Y, Wijenayake S, Storey KB. MAP kinase signaling and Elk1 transcriptional activity in hibernating thirteen-lined ground squirrels. Biochim Biophys Acta Gen Subj 2017; 1861:2811-2821. [DOI: 10.1016/j.bbagen.2017.07.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/07/2017] [Accepted: 07/31/2017] [Indexed: 12/13/2022]
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Roberts PA, Fox J, Peirce N, Jones SW, Casey A, Greenhaff PL. Creatine ingestion augments dietary carbohydrate mediated muscle glycogen supercompensation during the initial 24 h of recovery following prolonged exhaustive exercise in humans. Amino Acids 2016; 48:1831-42. [PMID: 27193231 PMCID: PMC4974290 DOI: 10.1007/s00726-016-2252-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 05/03/2016] [Indexed: 11/29/2022]
Abstract
Muscle glycogen availability can limit endurance exercise performance. We previously demonstrated 5 days of creatine (Cr) and carbohydrate (CHO) ingestion augmented post-exercise muscle glycogen storage compared to CHO feeding alone in healthy volunteers. Here, we aimed to characterise the time-course of this Cr-induced response under more stringent and controlled experimental conditions and identify potential mechanisms underpinning this phenomenon. Fourteen healthy, male volunteers cycled to exhaustion at 70 % VO2peak. Muscle biopsies were obtained at rest immediately post-exercise and after 1, 3 and 6 days of recovery, during which Cr or placebo supplements (20 g day−1) were ingested along with a prescribed high CHO diet (37.5 kcal kg body mass−1 day−1, >80 % calories CHO). Oral-glucose tolerance tests (oral-GTT) were performed pre-exercise and after 1, 3 and 6 days of Cr and placebo supplementation. Exercise depleted muscle glycogen content to the same extent in both treatment groups. Creatine supplementation increased muscle total-Cr, free-Cr and phosphocreatine (PCr) content above placebo following 1, 3 and 6 days of supplementation (all P < 0.05). Creatine supplementation also increased muscle glycogen content noticeably above placebo after 1 day of supplementation (P < 0.05), which was sustained thereafter. This study confirmed dietary Cr augments post-exercise muscle glycogen super-compensation, and demonstrates this occurred during the initial 24 h of post-exercise recovery (when muscle total-Cr had increased by <10 %). This marked response ensued without apparent treatment differences in muscle insulin sensitivity (oral-GTT, muscle GLUT4 mRNA), osmotic stress (muscle c-fos and HSP72 mRNA) or muscle cell volume (muscle water content) responses, such that another mechanism must be causative.
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Affiliation(s)
- Paul A Roberts
- School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - John Fox
- School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Nicholas Peirce
- School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Simon W Jones
- School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Anna Casey
- Human Metabolic Physiology and Nutrition, QinetiQ Centre for Human Sciences, Farnborough, UK
| | - Paul L Greenhaff
- School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK. .,School of Life Sciences, The Medical School, Nottingham, NG7 2UH, UK.
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15
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Davis RVN, Lamont SJ, Rothschild MF, Persia ME, Ashwell CM, Schmidt CJ. Transcriptome analysis of post-hatch breast muscle in legacy and modern broiler chickens reveals enrichment of several regulators of myogenic growth. PLoS One 2015; 10:e0122525. [PMID: 25821972 PMCID: PMC4379050 DOI: 10.1371/journal.pone.0122525] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 02/21/2015] [Indexed: 11/19/2022] Open
Abstract
Agriculture provides excellent model systems for understanding how selective pressure, as applied by humans, can affect the genomes of plants and animals. One such system is modern poultry breeding in which intensive genetic selection has been applied for meat production in the domesticated chicken. As a result, modern meat-type chickens (broilers) exhibit enhanced growth, especially of the skeletal muscle, relative to their legacy counterparts. Comparative studies of modern and legacy broiler chickens provide an opportunity to identify genes and pathways affected by this human-directed evolution. This study used RNA-seq to compare the transcriptomes of a modern and a legacy broiler line to identify differentially enriched genes in the breast muscle at days 6 and 21 post-hatch. Among the 15,945 genes analyzed, 10,841 were expressed at greater than 0.1 RPKM. At day 6 post-hatch 189 genes, including several regulators of myogenic growth and development, were differentially enriched between the two lines. The transcriptional profiles between lines at day 21 post-hatch identify 193 genes differentially enriched and still include genes associated with myogenic growth. This study identified differentially enriched genes that regulate myogenic growth and differentiation between the modern and legacy broiler lines. Specifically, differences in the ratios of several positive (IGF1, IGF1R, WFIKKN2) and negative (MSTN, ACE) myogenic growth regulators may help explain the differences underlying the enhanced growth characteristics of the modern broilers.
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Affiliation(s)
- Richard V. N. Davis
- Dept. Biological Sciences, University of Delaware, Newark, Delaware, 19716, United States of America
| | - Susan J. Lamont
- Dept. of Animal Science, Iowa State University, Ames, Iowa, 50011, United States of America
| | - Max F. Rothschild
- Dept. of Animal Science, Iowa State University, Ames, Iowa, 50011, United States of America
| | - Michael E. Persia
- Dept. of Animal Science, Iowa State University, Ames, Iowa, 50011, United States of America
| | - Chris M. Ashwell
- Dept. of Poultry Science, North Carolina State University, Raleigh, North Carolina, 27695, United States of America
| | - Carl J. Schmidt
- Dept. of Animal and Food Sciences, University of Delaware, Newark, Delaware, 19716, United States of America
- * E-mail:
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Rylova JV, Buravkova LB. Long-term expansion of multipotent mesenchymal stromal cells under reduced oxygen tension. ACTA ACUST UNITED AC 2014. [DOI: 10.1134/s1990519x14020084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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17
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Neubauer O, Sabapathy S, Ashton KJ, Desbrow B, Peake JM, Lazarus R, Wessner B, Cameron-Smith D, Wagner KH, Haseler LJ, Bulmer AC. Time course-dependent changes in the transcriptome of human skeletal muscle during recovery from endurance exercise: from inflammation to adaptive remodeling. J Appl Physiol (1985) 2013; 116:274-87. [PMID: 24311745 DOI: 10.1152/japplphysiol.00909.2013] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Reprogramming of gene expression is fundamental for skeletal muscle adaptations in response to endurance exercise. This study investigated the time course-dependent changes in the muscular transcriptome after an endurance exercise trial consisting of 1 h of intense cycling immediately followed by 1 h of intense running. Skeletal muscle samples were taken at baseline, 3 h, 48 h, and 96 h postexercise from eight healthy, endurance-trained men. RNA was extracted from muscle. Differential gene expression was evaluated using Illumina microarrays and validated with qPCR. Gene set enrichment analysis identified enriched molecular signatures chosen from the Molecular Signatures Database. Three hours postexercise, 102 gene sets were upregulated [family wise error rate (FWER), P < 0.05], including groups of genes related with leukocyte migration, immune and chaperone activation, and cyclic AMP responsive element binding protein (CREB) 1 signaling. Forty-eight hours postexercise, among 19 enriched gene sets (FWER, P < 0.05), two gene sets related to actin cytoskeleton remodeling were upregulated. Ninety-six hours postexercise, 83 gene sets were enriched (FWER, P < 0.05), 80 of which were upregulated, including gene groups related to chemokine signaling, cell stress management, and extracellular matrix remodeling. These data provide comprehensive insights into the molecular pathways involved in acute stress, recovery, and adaptive muscular responses to endurance exercise. The novel 96 h postexercise transcriptome indicates substantial transcriptional activity potentially associated with the prolonged presence of leukocytes in the muscles. This suggests that muscular recovery, from a transcriptional perspective, is incomplete 96 h after endurance exercise involving muscle damage.
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Affiliation(s)
- Oliver Neubauer
- Emerging Field Oxidative Stress and DNA Stability, Research Platform Active Aging, and Department of Nutritional Sciences, University of Vienna, Austria
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Early activation of rat skeletal muscle IL-6/STAT1/STAT3 dependent gene expression in resistance exercise linked to hypertrophy. PLoS One 2013; 8:e57141. [PMID: 23451164 PMCID: PMC3579782 DOI: 10.1371/journal.pone.0057141] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 01/17/2013] [Indexed: 11/19/2022] Open
Abstract
Cytokine interleukin-6 (IL-6) is an essential regulator of satellite cell-mediated hypertrophic muscle growth through the transcription factor signal transducer and activator of transcription 3 (STAT3). The importance of this pathway linked to the modulation of myogenic regulatory factors expression in rat skeletal muscle undergoing hypertrophy following resistance exercise, has not been investigated. In this study, the phosphorylation and nuclear localization of STAT3, together with IL-6/STAT3-responsive gene expression, were measured after both a single bout of resistance exercise and 10 weeks of training. Flexor Digitorum Profundus muscle samples from Wistar rats were obtained 2 and 6 hours after a single bout of resistance exercise and 72 h after the last bout of either 2, 4, or 10 weeks of resistance training. We observed an increase in IL-6 and SOCS3 mRNAs concomitant with phosphorylation of STAT1 and STAT3 after 2 and 6 hours of a single bout of exercise (p<0.05). STAT3-dependent early responsive genes such as CyclinD1 and cMyc were also upregulated whereas MyoD and Myf5 mRNAs were downregulated (p<0.05). BrdU-positive satellite cells increased at 2 and 6 hours after exercise (p<0.05). Muscle fiber hypertrophy reached up to 100% after 10 weeks of training and the mRNA expression of Myf5, c-Myc and Cyclin-D1 decreased, whereas IL-6 mRNA remained upregulated. We conclude that the IL-6/STAT1/STAT3 signaling pathway and its responsive genes after a single bout of resistance exercise are an important event regulating the SC pool and behavior involved in muscle hypertrophy after ten weeks of training in rat skeletal muscle.
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Tamboli RA, Hajri T, Jiang A, Marks-Shulman PA, Williams DB, Clements RH, Melvin W, Bowen BP, Shyr Y, Abumrad NN, Flynn CR. Reduction in inflammatory gene expression in skeletal muscle from Roux-en-Y gastric bypass patients randomized to omentectomy. PLoS One 2011; 6:e28577. [PMID: 22194858 PMCID: PMC3241684 DOI: 10.1371/journal.pone.0028577] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Accepted: 11/10/2011] [Indexed: 12/19/2022] Open
Abstract
Objectives To examine the effects of Roux-en-Y gastric bypass (RYGB) surgery with and without laparoscopic removal of omental fat (omentectomy) on the temporal gene expression profiles of skeletal muscle. Design Previously reported were the whole-body metabolic effects of a randomized, single-blinded study in patients receiving RYGB surgery stratified to receive or not receive omentectomy. In this follow up study we report on changes in skeletal muscle gene expression in a subset of 21 patients, for whom biopsies were collected preoperatively and at either 6 months or 12 months postoperatively. Methodology/Principal Findings RNA isolated from skeletal muscle biopsies of 21 subjects (8 without omentectomy and 13 with omentectomy) taken before RYGB or at 6 and 12 months postoperatively were subjected to gene expression profiling via Exon 1.0 S/T Array and Taqman Low Density Array. Robust Multichip Analysis and gene enrichment data analysis revealed 84 genes with at least a 4-fold expression difference after surgery. At 6 and 12 months the RYGB with omentectomy group displayed a greater reduction in the expression of genes associated with skeletal muscle inflammation (ANKRD1, CDR1, CH25H, CXCL2, CX3CR1, IL8, LBP, NFIL3, SELE, SOCS3, TNFAIP3, and ZFP36) relative to the RYGB non-omentectomy group. Expressions of IL6 and CCL2 were decreased at all postoperative time points. There was differential expression of genes driving protein turnover (IGFN1, FBXW10) in both groups over time and increased expression of PAAF1 in the non-omentectomy group at 12 months. Evidence for the activation of skeletal muscle satellite cells was inferred from the up-regulation of HOXC10. The elevated post-operative expression of 22 small nucleolar RNAs and the decreased expression of the transcription factors JUNB, FOS, FOSB, ATF3 MYC, EGR1 as well as the orphan nuclear receptors NR4A1, NR4A2, NR4A3 suggest dramatic reorganizations at both the cellular and genetic levels. Conclusions/Significance These data indicate that RYGB reduces skeletal muscle inflammation, and removal of omental fat further amplifies this response. Trial Registration ClinicalTrials.gov NCT00212160
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Affiliation(s)
- Robyn A. Tamboli
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Tahar Hajri
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Aixiang Jiang
- Department of Cancer Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Pamela A. Marks-Shulman
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - D. Brandon Williams
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Ronald H. Clements
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Willie Melvin
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Benjamin P. Bowen
- Department of GTL Bioenergy and Structural Biology, Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Yu Shyr
- Department of Cancer Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Naji N. Abumrad
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Charles Robb Flynn
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- * E-mail:
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Wallace MA, Hock MB, Hazen BC, Kralli A, Snow RJ, Russell AP. Striated muscle activator of Rho signalling (STARS) is a PGC-1α/oestrogen-related receptor-α target gene and is upregulated in human skeletal muscle after endurance exercise. J Physiol 2011; 589:2027-39. [PMID: 21486805 PMCID: PMC3090601 DOI: 10.1113/jphysiol.2011.205468] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 02/15/2011] [Indexed: 01/26/2023] Open
Abstract
The striated muscle activator of Rho signalling (STARS) is an actin-binding protein specifically expressed in cardiac, skeletal and smooth muscle. STARS has been suggested to provide an important link between the transduction of external stress signals to intracellular signalling pathways controlling genes involved in the maintenance of muscle function. The aims of this study were firstly, to establish if STARS, as well as members of its downstream signalling pathway, are upregulated following acute endurance cycling exercise; and secondly, to determine if STARS is a transcriptional target of peroxisome proliferator-activated receptor gamma co-activator 1-α (PGC-1α) and oestrogen-related receptor-α (ERRα). When measured 3 h post-exercise, STARS mRNA and protein levels as well as MRTF-A and serum response factor (SRF) nuclear protein content, were significantly increased by 140, 40, 40 and 40%, respectively. Known SRF target genes, carnitine palmitoyltransferase-1β (CPT-1β) and jun B proto-oncogene (JUNB), as well as the exercise-responsive genes PGC-1α mRNA and ERRα were increased by 2.3-, 1.8-, 4.5- and 2.7-fold, 3 h post-exercise. Infection of C2C12 myotubes with an adenovirus-expressing human PGC-1α resulted in a 3-fold increase in Stars mRNA, a response that was abolished following the suppression of endogenous ERRα. Over-expression of PGC-1α also increased Cpt-1β, Cox4 and Vegf mRNA by 6.2-, 2.0- and 2.0-fold, respectively. Suppression of endogenous STARS reduced basal Cpt-1β levels by 8.2-fold and inhibited the PGC-1α-induced increase in Cpt-1β mRNA. Our results show for the first time that the STARS signalling pathway is upregulated in response to acute endurance exercise. Additionally, we show in C2C12 myotubes that the STARS gene is a PGC-1α/ERRα transcriptional target. Furthermore, our results suggest a novel role of STARS in the co-ordination of PGC-1α-induced upregulation of the fat oxidative gene, CPT-1β.
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Affiliation(s)
- Marita A Wallace
- Centre for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Burwood 3125, Australia
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Caldow MK, Steinberg GR, Cameron-Smith D. Impact of SOCS3 overexpression on human skeletal muscle development in vitro. Cytokine 2011; 55:104-9. [PMID: 21478033 DOI: 10.1016/j.cyto.2011.03.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 03/14/2011] [Accepted: 03/15/2011] [Indexed: 12/26/2022]
Abstract
The Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling cascade has been identified as a crucial factor for myogenesis. The STAT3 isoform is essential for satellite cell migration and myogenic differentiation as it mediates the expression of muscle specific myogenic factors. The SOCS (suppressors of cytokine signaling) family of proteins down-regulates STAT activation. Primary human skeletal muscle cells were isolated and cultured to investigate the effect of SOCS3 adenoviral overexpression on myotube maturation. It was demonstrated that STAT3 inhibition did not influence myotube development or survival. Moreover, SOCS3 overexpression enhances the mRNA expression of downstream targets of STAT3, c-FOS and VEGF. These increases were correlated with enhanced mRNA expression of genes associated with muscle maturation and hypertrophy. Thus SOCS3 influences myoblast differentiation and SOCS3 may be significant in regulating the activity of genes previously identified as transcriptionally regulated by STAT3.
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Affiliation(s)
- Marissa K Caldow
- Molecular Nutrition Unit, School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia.
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22
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Nguyen LMD, Hood DA. Contractile activity-induced gene expression in fast- and slow-twitch muscle. Appl Physiol Nutr Metab 2011; 36:233-41. [DOI: 10.1139/h11-004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Linda M.-D. Nguyen
- School of Kinesiology and Health Science, The Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - David A. Hood
- School of Kinesiology and Health Science, The Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
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Sigala I, Zacharatos P, Toumpanakis D, Michailidou T, Noussia O, Theocharis S, Roussos C, Papapetropoulos A, Vassilakopoulos T. MAPKs and NF-κB differentially regulate cytokine expression in the diaphragm in response to resistive breathing: the role of oxidative stress. Am J Physiol Regul Integr Comp Physiol 2011; 300:R1152-62. [PMID: 21325641 DOI: 10.1152/ajpregu.00376.2010] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Inspiratory resistive breathing (IRB) induces cytokine expression in the diaphragm. The mechanism of this cytokine induction remains elusive. The roles of MAPKs and NF-κB and the impact of oxidative stress in IRB-induced cytokine upregulation in the diaphragm were studied. Wistar rats were subjected to IRB (50% of maximal inspiratory pressure) via a two-way nonrebreathing valve for 1, 3, or 6 h. Additional groups of rats subjected to IRB for 6 h were randomly assigned to receive either solvent or N-acetyl-cysteine (NAC) or inhibitors of NF-κB (BAY-11-7082), ERK1/2 (PD98059), and P38 MAPK (SB203580) to study the effect of oxidative stress, NF-κB, and MAPKs in IRB-induced cytokine upregulation in the diaphragm. Quietly breathing animals served as controls. IRB upregulated cytokine (IL-6, TNF-α, IL-10, IL-2, IL-1β) protein levels in the diaphragm and resulted in increased activation of MAPKs (P38, ERK1/2) and NF-κB. Inhibition of NF-κB and ERK1/2 blunted the upregulation of all cytokines except that of IL-6, which was further increased. P38 inhibition attenuated all cytokine (including IL-6) upregulation. Both P38 and ERK1/2 inhibition decreased NF-κB/p65 subunit phosphorylation. NAC pretreatment blunted IRB-induced cytokine upregulation in the diaphragm and resulted in decreased ERK1/2, P38, and NF-κB/p65 phosphorylation. In conclusion, IRB-induced cytokine upregulation in the diaphragm is under the regulatory control of MAPKs and NF-κB. IL-6 is regulated differently from all other cytokines through a P38-dependent and NF-κB independent pathway. Oxidative stress is a stimulus for IRB-induced cytokine upregulation in the diaphragm.
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Affiliation(s)
- Ioanna Sigala
- Dept. of Critical Care and Pulmonary Services, University of Athens Medical School, Evangelismos Hospital, 45-47 Ipsilandou Str., Athens, Greece
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Trenerry MK, Della Gatta PA, Larsen AE, Garnham AP, Cameron-Smith D. Impact of resistance exercise training on interleukin-6 and JAK/STAT in young men. Muscle Nerve 2010; 43:385-92. [DOI: 10.1002/mus.21875] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2010] [Indexed: 02/04/2023]
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Effect of Treadmill Exercise on Leak-point pressure and Neuronal Activation in Brain of Rats with Stress Urinary Incontinence. Int Neurourol J 2010; 14:141-8. [PMID: 21179331 DOI: 10.5213/inj.2010.14.3.141] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 11/09/2009] [Indexed: 02/02/2023] Open
Abstract
PURPOSE Stress urinary incontinence (SUI) commonly occurs in women, and it causes enormous impact on quality of life. Surgery, drugs, and exercise have been recommended for the treatment of this disease. Among these exercise is also known to be effective for relieving thesymptoms of SUI, however, the efficacy and underlying mechanisms of exercise on SUI are poorly understood. In the present study, we investigated the effect of treadmill exercise on abdominal leak-point pressure and neuronal activity in the medial preoptic nucleus (MPA), ventrolateral periaqueductal gray (vlPAG), and pontine micturition center (PMC) following urethrolysis in rats. MATERIALS AND METHODS Adult female Sprague-Dawley rats, weighing 250±10 g (9 weeks old), were used in this study. After having undergone transabdominal urethrolysis to induce SUI, the rats were divided into three groups (n=6 in each group): a sham operation group, an SUI-induced group, and an SUI-induced and treadmill exercise group. The rats in the exercise group performed treadmill running for 30 min once a day starting 2 weeks after the induction of SUI and continuing for 4 weeks after surgery. For this study, determination of abdominal leak point pressure and immunohistochemistry for c-Fos in the brain were performed. RESULTS Induction of transabdominal urethrolysis significantly reduced the abdominal leak point pressure, thereby contributing to the induction of SUI. In contrast, abdominal leak point pressure was significantly improved by treadmill exercise. The expression of c-Fosin the MPA, vlPAG, and PMC, the brain areas relating to micturition, was enhanced by the induction of SUI, whereas treadmill exercise significantly suppressed SUI-induced c-Fos expression, suggesting that neuronal activation in the micturition centers was suppressed by treadmill exercise. CONCLUSION The present results suggest that treadmill exercise may be an effective therapeutic modality for ameliorating the symptoms of SUI.
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Hoene M, Franken H, Fritsche L, Lehmann R, Pohl AK, Häring HU, Zell A, Schleicher ED, Weigert C. Activation of the mitogen-activated protein kinase (MAPK) signalling pathway in the liver of mice is related to plasma glucose levels after acute exercise. Diabetologia 2010; 53:1131-41. [PMID: 20195842 DOI: 10.1007/s00125-010-1666-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 12/17/2009] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS We aimed to identify, in the liver of mice, signal transduction pathways that show a pronounced regulation by acute exercise. We also aimed to elucidate the role of metabolic stress in this response. METHODS C57Bl6 mice performed a 60 min run on a treadmill under non-exhaustive conditions. Hepatic RNA and protein lysates were prepared immediately after running and used for whole-genome-expression analysis, quantitative real-time PCR and immunoblotting. A subset of mice recovered for 3 h after the treadmill run. A further group of mice performed the treadmill run after having received a vitamin C- and vitamin E-enriched diet over 4 weeks. RESULTS The highest number of genes differentially regulated by exercise in the liver was found in the mitogen-activated protein kinase (MAPK) signalling pathway, with a pronounced and transient upregulation of the transcription factors encoded by c-Fos (also known as Fos), c-Jun (also known as Jun), FosB (also known as Fosb) and JunB (also known as Junb) and phosphorylation of hepatic MAPK. Acute exercise also activated the p53 signalling pathway. A major role for oxidative stress is unlikely since the antioxidant-enriched diet did not prevent the activation of the MAPK pathway. In contrast, lower plasma glucose levels after running were related to enhanced levels of MAPK signalling proteins, similar to the upregulation of Igfbp1 and Pgc-1alpha (also known as Ppargc1a). In the working muscle the activation of the MAPK pathway was weak and not related to plasma glucose concentrations. CONCLUSIONS/INTERPRETATION Metabolic stress evidenced as low plasma glucose levels appears to be an important determinant for the activation of the MAPK signalling pathway and the transcriptional response of the liver to acute exercise.
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Affiliation(s)
- M Hoene
- Division of Endocrinology, Diabetology, Angiology, Nephrology, Pathobiochemistry and Clinical Chemistry, Department of Internal Medicine, University Hospital of Tuebingen, Otfried-Mueller-Strasse 10, D-72076 Tuebingen, Germany
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Mounier R, Pedersen BK, Plomgaard P. Muscle-specific expression of hypoxia-inducible factor in human skeletal muscle. Exp Physiol 2010; 95:899-907. [PMID: 20494919 DOI: 10.1113/expphysiol.2010.052928] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Skeletal muscle is well known to exhibit a high degree of plasticity depending on environmental changes, such as various oxygen concentrations. Studies of the oxygen-sensitive subunit alpha of hypoxia-inducible factor-1 (HIF-1) are difficult owing to the large variety of functionally diverse muscle fibres that possess unique patterns of protein and gene expression, producing different capillarization and energy metabolism systems. In this work, we analysed HIF-1alpha mRNA and protein expression related to the fibre-type composition in untrained human skeletal muscle by obtaining muscle biopsies from triceps brachii (characterized by a high proportion of type II fibres), from soleus (characterized by a high proportion of type I fibres) and from vastus lateralis (characterized by an equal proportion of type I and II fibres). The hypothesis was that type I muscle fibres would have lower HIF-1alpha mRNA and protein owing to their higher oxidative capacity. We have shown, in normoxic conditions, a higher HIF-1alpha protein expression in predominantly oxidative muscles than in predominantly glycolytic muscles. However, the HIF-1alpha mRNA expression pattern was not in agreement with the HIF-1alpha protein level. Interestingly, none of the HIF-1alpha target genes, like the most studied angiogenic factor involved in muscle angiogenesis, vascular endothelial growth factor (VEGF), exhibited a muscle fibre-specific-related mRNA expression at rest in normoxia. However, soleus presented a significantly higher VEGF protein content than vastus lateralis and triceps muscle. In conclusion, we have shown that there are muscle-specific differences in HIF-1alpha and VEGF expression within human skeletal muscle at rest in normoxic conditions. Recent results, when combined with the findings described here, support a key role for HIF-1alpha for maintaining muscle homeostasis in non-hypoxic conditions.
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Affiliation(s)
- Rémi Mounier
- Centre of Inflammation and Metabolism, Department of Infectious Diseases, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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MacNeil LG, Melov S, Hubbard AE, Baker SK, Tarnopolsky MA. Eccentric exercise activates novel transcriptional regulation of hypertrophic signaling pathways not affected by hormone changes. PLoS One 2010; 5:e10695. [PMID: 20502695 PMCID: PMC2872670 DOI: 10.1371/journal.pone.0010695] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 04/16/2010] [Indexed: 01/21/2023] Open
Abstract
Unaccustomed eccentric exercise damages skeletal muscle tissue, activating mechanisms of recovery and remodeling that may be influenced by the female sex hormone 17β-estradiol (E2). Using high density oligonucleotide based microarrays, we screened for differences in mRNA expression caused by E2 and eccentric exercise. After random assignment to 8 days of either placebo (CON) or E2 (EXP), eighteen men performed 150 single-leg eccentric contractions. Muscle biopsies were collected at baseline (BL), following supplementation (PS), +3 hours (3H) and +48 hours (48H) after exercise. Serum E2 concentrations increased significantly with supplementation (P<0.001) but did not affect microarray results. Exercise led to early transcriptional changes in striated muscle activator of Rho signaling (STARS), Rho family GTPase 3 (RND3), mitogen activated protein kinase (MAPK) regulation and the downstream transcription factor FOS. Targeted RT-PCR analysis identified concurrent induction of negative regulators of calcineurin signaling RCAN (P<0.001) and HMOX1 (P = 0.009). Protein contents were elevated for RND3 at 3H (P = 0.02) and FOS at 48H (P<0.05). These findings indicate that early RhoA and NFAT signaling and regulation are altered following exercise for muscle remodeling and repair, but are not affected by E2.
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Affiliation(s)
- Lauren G. MacNeil
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Simon Melov
- Buck Institute for Age Research, Novato, California, United States of America
| | - Alan E. Hubbard
- School of Public Health, University of California, Berkeley, California, United States of America
| | - Steven K. Baker
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Mark A. Tarnopolsky
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
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McGivney BA, Eivers SS, MacHugh DE, MacLeod JN, O'Gorman GM, Park SDE, Katz LM, Hill EW. Transcriptional adaptations following exercise in thoroughbred horse skeletal muscle highlights molecular mechanisms that lead to muscle hypertrophy. BMC Genomics 2009; 10:638. [PMID: 20042072 PMCID: PMC2812474 DOI: 10.1186/1471-2164-10-638] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Accepted: 12/30/2009] [Indexed: 12/23/2022] Open
Abstract
Background Selection for exercise-adapted phenotypes in the Thoroughbred racehorse has provided a valuable model system to understand molecular responses to exercise in skeletal muscle. Exercise stimulates immediate early molecular responses as well as delayed responses during recovery, resulting in a return to homeostasis and enabling long term adaptation. Global mRNA expression during the immediate-response period has not previously been reported in skeletal muscle following exercise in any species. Also, global gene expression changes in equine skeletal muscle following exercise have not been reported. Therefore, to identify novel genes and key regulatory pathways responsible for exercise adaptation we have used equine-specific cDNA microarrays to examine global mRNA expression in skeletal muscle from a cohort of Thoroughbred horses (n = 8) at three time points (before exercise, immediately post-exercise, and four hours post-exercise) following a single bout of treadmill exercise. Results Skeletal muscle biopsies were taken from the gluteus medius before (T0), immediately after (T1) and four hours after (T2) exercise. Statistically significant differences in mRNA abundance between time points (T0 vs T1 and T0 vs T2) were determined using the empirical Bayes moderated t-test in the Bioconductor package Linear Models for Microarray Data (LIMMA) and the expression of a select panel of genes was validated using real time quantitative reverse transcription PCR (qRT-PCR). While only two genes had increased expression at T1 (P < 0.05), by T2 932 genes had increased (P < 0.05) and 562 genes had decreased expression (P < 0.05). Functional analysis of genes differentially expressed during the recovery phase (T2) revealed an over-representation of genes localized to the actin cytoskeleton and with functions in the MAPK signalling, focal adhesion, insulin signalling, mTOR signaling, p53 signaling and Type II diabetes mellitus pathways. At T1, using a less stringent statistical approach, we observed an over-representation of genes involved in the stress response, metabolism and intracellular signaling. These findings suggest that protein synthesis, mechanosensation and muscle remodeling contribute to skeletal muscle adaptation towards improved integrity and hypertrophy. Conclusions This is the first study to characterize global mRNA expression profiles in equine skeletal muscle using an equine-specific microarray platform. Here we reveal novel genes and mechanisms that are temporally expressed following exercise providing new knowledge about the early and late molecular responses to exercise in the equine skeletal muscle transcriptome.
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Affiliation(s)
- Beatrice A McGivney
- Animal Genomics Laboratory, UCD School of Agriculture, Food Science and Veterinary Medicine, UCD College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland.
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Buford TW, Cooke MB, Willoughby DS. Resistance exercise-induced changes of inflammatory gene expression within human skeletal muscle. Eur J Appl Physiol 2009; 107:463-71. [PMID: 19669788 DOI: 10.1007/s00421-009-1145-z] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2009] [Indexed: 01/06/2023]
Abstract
Aberrant local inflammatory signaling within skeletal muscle is now considered a contributing factor to the development of sarcopenia. Recent evidence indicates that chronic resistance training contributes to the control of locally derived inflammation via adaptations to repeated, acute increases in pro-inflammatory mRNA within muscle. However, only a limited number of gene transcripts related to the inflammatory process have been examined in the literature. The present study utilized an acute bout to examine the effects of resistance exercise on several inflammatory-related genes in 24 physically active, post-menopausal women not currently undergoing hormone replacement therapy. Following a standard warm-up, participants completed a lower-body resistance exercise bout consisting of 3 sets of 10 repetitions on machine squat, leg press, and leg extension exercises (80% intensity). Muscle biopsies were obtained from the vastus lateralis of the dominant leg at baseline and 3 h following exercise. Significant (p < 0.05) up-regulation in mRNA content was observed for TNFalpha, IL1beta, IL6, IL8, SOCS2, COX2, SAA1, SAA2, IKKB, cfos, and junB. Muscle mRNA content was not significantly altered at the 0.05 level for IL2, IL5, IL10, or IL12 (p35). Venous blood samples were also obtained at baseline as well as at 3, 24, and 48 h post-exercise. Serum was analyzed for circulating TNFalpha, IL1beta, IL6, IL8, COX2, and SAA with no significant changes observed. These results indicate that resistance exercise is capable of up-regulating transcription of numerous inflammatory mediators within skeletal muscle, and these appear to be worthy of future examination in chronic studies.
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Affiliation(s)
- Thomas W Buford
- Division of Medicine, Department of Aging and Geriatric Research, Institute on Aging, University of Florida, Gainesville, FL, USA
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31
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Effect of intermittent hypoxic training on HIF gene expression in human skeletal muscle and leukocytes. Eur J Appl Physiol 2008; 105:515-24. [PMID: 19018560 DOI: 10.1007/s00421-008-0928-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2008] [Indexed: 01/08/2023]
Abstract
Intermittent hypoxic exposure with exercise training is based on the assumption that brief exposure to hypoxia is sufficient to induce beneficial muscular adaptations mediated via hypoxia-inducible transcription factors (HIF). We previously demonstrated (Mounier et al. Med Sci Sports Exerc 38:1410-1417, 2006) that leukocytes respond to hypoxia with a marked inter-individual variability in HIF-1alpha mRNA. This study compared the effects of 3 weeks of intermittent hypoxic training on hif gene expression in both skeletal muscle and leukocytes. Male endurance athletes (n = 19) were divided into an Intermittent Hypoxic Exposure group (IHE) and a Normoxic Training group (NT) with each group following a similar 3-week exercise training program. After training, the amount of HIF-1alpha mRNA in muscle decreased only in IHE group (-24.7%, P < 0.05) whereas it remained unchanged in leukocytes in both groups. The levels of vEGF(121) and vEGF(165) mRNA in skeletal muscle increased significantly after training only in the NT group (+82.5%, P < 0.05 for vEGF(121); +41.2%, P < 0.05 for vEGF(165)). In leukocytes, only the IHE group showed a significant change in vEGF(165) (-28.2%, P < 0.05). The significant decrease in HIF-1alpha mRNA in skeletal muscle after hypoxic training suggests that transcriptional and post-transcriptional regulations of the hif-1alpha gene are different in muscle and leukocytes.
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Trenerry MK, Carey KA, Ward AC, Farnfield MM, Cameron-Smith D. Exercise-induced activation of STAT3 signaling is increased with age. Rejuvenation Res 2008; 11:717-24. [PMID: 18729804 DOI: 10.1089/rej.2007.0643] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Activation of the transcription factor signal transducers and activators of transcription (STAT) 3 is common to many inflammatory cytokines and growth factors, with recent evidence of involvement in skeletal muscle regeneration. The purpose of this study was to determine whether STAT3 signaling activation is regulated differentially, at rest and following intense resistance exercise, in aged human skeletal muscle. Skeletal muscle biopsies were harvested from healthy younger (n = 11, 20.4 +/- 0.8 years) and older men (n = 10, 67.4 +/- 1.3 years) under resting conditions and 2 h after the completion of resistance exercise. No differences were evident at rest, whereas the phosphorylation of STAT3 was significantly increased in old (23-fold) compared to young (5-fold) subjects after exercise. This correlated with significantly higher induction of the STAT3 target genes including; interleukin-6 (IL-6), JUNB, c-MYC, and suppressor of cytokine signaling (SOCS) 3 mRNA in older subjects following exercise. Despite increased SOCS3 mRNA, cellular protein abundance was suppressed. SOCS3 protein is an important negative regulator of STAT3 activation and cytokine signaling. Thus, in aged human muscle, elevated responsiveness of the STAT3 signaling pathway and suppressed SOCS3 protein are evident following resistance exercise. These data suggest that enhanced STAT3 signaling responsiveness to proinflammatory factors may impact on mechanisms of muscle repair and regeneration.
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Affiliation(s)
- Marissa K Trenerry
- School of Exercise and Nutrition Science, Deakin University, 221 Burwood Highway, Burwood, Victoria 3125, Australia
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Hoene M, Lehmann R, Hennige AM, Pohl AK, Häring HU, Schleicher ED, Weigert C. Acute regulation of metabolic genes and insulin receptor substrates in the liver of mice by one single bout of treadmill exercise. J Physiol 2008; 587:241-52. [PMID: 19001047 DOI: 10.1113/jphysiol.2008.160275] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Acute exercise performance represents a major metabolic challenge for the skeletal muscle, but also for the liver as the most important source of energy. However the molecular adaptation of the liver to one single bout of exercise is largely unknown. C57BL/6 mice performed a 60 min treadmill run at high aerobic intensity. Liver, soleus and white gastrocnemius muscle were removed immediately after exercise. The single bout of exercise resulted in a very rapid and pronounced induction of hepatic metabolic enzymes and regulators of metabolism or transcription: glucose-6-phosphatase (G6Pase; 3-fold), pyruvate dehydrogenase kinase-4 (PDK4; 4.8-fold), angiopoietin-like 4 (2.1-fold), insulin receptor substrate (IRS)-2 (5.1-fold), peroxisome proliferator activated receptor-gamma coactivator 1alpha (PGC-1alpha; 3-fold). In soleus and white gastrocnemius muscle the up-regulation of IRS-2 and PDK4 was less pronounced compared with the liver and no significant induction of PGC-1alpha could be detected at this early time point. Activation of AMPK was found in both liver and white gastrocnemius muscle as phosphorylation of Thr-172. The induction of endogenous insulin secretion by a glucose load directly after the exercise bout resulted in a significantly higher PKB/Akt phosphorylation in the liver of exercised mice. The markedly enhanced IRS-2 protein amount, and presumably reduced serine/threonine phosphorylation of the IRS proteins induced by the acute exercise could be responsible for this enhanced action of insulin. In conclusion, acute exercise induced a rapid and pronounced transcriptional adaptation in the liver, and regulated hepatic IRS proteins leading to improved cellular insulin signal transduction.
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Affiliation(s)
- Miriam Hoene
- Division of Pathobiochemistry and Clinical Chemistry, University of Tuebingen, Otfried-Mueller-Strasse 10, D-72076 Tuebingen, Germany
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Pérez R, Tupac-Yupanqui I, Dunner S. Evaluation of suitable reference genes for gene expression studies in bovine muscular tissue. BMC Mol Biol 2008; 9:79. [PMID: 18786244 PMCID: PMC2561043 DOI: 10.1186/1471-2199-9-79] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2008] [Accepted: 09/11/2008] [Indexed: 11/24/2022] Open
Abstract
Background Real-time reverse transcriptase quantitative polymerase chain reaction (real-time RTqPCR) is a technique used to measure mRNA species copy number as a way to determine key genes involved in different biological processes. However, the expression level of these key genes may vary among tissues or cells not only as a consequence of differential expression but also due to different factors, including choice of reference genes to normalize the expression levels of the target genes; thus the selection of reference genes is critical for expression studies. For this purpose, ten candidate reference genes were investigated in bovine muscular tissue. Results The value of stability of ten candidate reference genes included in three groups was estimated: the so called 'classical housekeeping' genes (18S, GAPDH and ACTB), a second set of genes used in expression studies conducted on other tissues (B2M, RPII, UBC and HMBS) and a third set of novel genes (SF3A1, EEF1A2 and CASC3). Three different statistical algorithms were used to rank the genes by their stability measures as produced by geNorm, NormFinder and Bestkeeper. The three methods tend to agree on the most stably expressed genes and the least in muscular tissue. EEF1A2 and HMBS followed by SF3A1, ACTB, and CASC3 can be considered as stable reference genes, and B2M, RPII, UBC and GAPDH would not be appropriate. Although the rRNA-18S stability measure seems to be within the range of acceptance, its use is not recommended because its synthesis regulation is not representative of mRNA levels. Conclusion Based on geNorm algorithm, we propose the use of three genes SF3A1, EEF1A2 and HMBS as references for normalization of real-time RTqPCR in muscle expression studies.
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Affiliation(s)
- Raquel Pérez
- Dpt. Animal Production, Veterinary Faculty, University Complutense of Madrid, 28040 Madrid, Spain.
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Allam M, Julien N, Zacharie B, Penney C, Gagnon L. Enhancement of Th1 type cytokine production and primary T cell activation by PBI-1393. Clin Immunol 2007; 125:318-27. [PMID: 17827067 DOI: 10.1016/j.clim.2007.07.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 07/26/2007] [Accepted: 07/27/2007] [Indexed: 11/15/2022]
Abstract
In previous reports, we have shown that PBI-1393 (formerly BCH-1393), N,N-Dimethylaminopurine pentoxycarbonyl D-arginine, stimulates cytotoxic T-lymphocyte (CTL) responses both in vitro and in vivo in normal immune status and immunosuppressed mice. Additionally, PBI-1393 was tested for anticancer activity in syngeneic mouse experimental tumor models and it displayed significant inhibition of tumor outgrowths when given in combination with sub-therapeutic doses of cytotoxic drugs (cyclophosphamide, 5-fluorouracil, doxorubicin and cis-platinum). However, the mechanism of action of PBI-1393 was still unknown. Here, we report that PBI-1393 enhances IL-2 and IFN-gamma production in human activated T cells by 51% and 46% respectively. PBI-1393 increases also IL-2 and IFN-gamma mRNA expression as shown by RT-PCR. The physiological relevance of IL-2 and IFN-gamma gene modulation by PBI-1393 is illustrated by the advantageous increase of T cell proliferation (39+/-0.3% above control) and human CTL response against prostate (PC-3) cancer cells (42+/-0.03%). The enhancement of human T cell proliferation and CTL activation by PBI-1393 demonstrates that this compound potentiates the immune response and in this regard, it could be used as an alternative approach to IL-2 and/or IFN-gamma therapy against cancer.
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Affiliation(s)
- Mustapha Allam
- ProMetic BioSciences Inc., 500 Cartier Blvd. West, Suite 150, Laval, Quebec, Canada H7V 5B7.
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Klossner S, Däpp C, Schmutz S, Vogt M, Hoppeler H, Flück M. Muscle transcriptome adaptations with mild eccentric ergometer exercise. Pflugers Arch 2007; 455:555-62. [PMID: 17701424 DOI: 10.1007/s00424-007-0303-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 04/12/2007] [Accepted: 05/29/2007] [Indexed: 01/09/2023]
Abstract
The muscle has a wide range of possibilities to adapt its phenotype. Repetitive submaximal concentric exercise (i.e., shortening contractions) mainly leads to adaptations of muscle oxidative metabolism and endurance while eccentric exercise (i.e., lengthening contractions) results in muscle growth and gain of muscle strength. Modified gene expression is believed to mediate these exercise-specific muscle adjustments. In the present study, early alterations of the gene expression signature were monitored by a muscle-specific microarray. Transcript profiling was performed on muscle biopsies of vastus lateralis obtained from six male subjects before and in a 24-h time course after a single bout of mild eccentric ergometer exercise. The eccentric exercise consisted of 15 min of eccentric cycling at 50% of the individual maximal concentric power output leading to muscle soreness (5.9 on a 0-10 visual analogue scale) and limited muscle damage (1.7-fold elevated creatine kinase activity). Muscle impairment was highlighted by a transient reduction in jumping height after the eccentric exercise. On the gene expression level, we observed a general early downregulation of detected transcripts, followed by a slow recovery close to the control values within the first 24 h post exercise. Only very few regulatory factors were increased. This expression signature is different from the signature of a previously published metabolic response after an intensive endurance-type concentric exercise as well as after maximal eccentric exercise. This is the first description of the time course of changes in gene expression as a consequence of a mild eccentric stimulus.
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Juretić N, Urzúa U, Munroe DJ, Jaimovich E, Riveros N. Differential gene expression in skeletal muscle cells after membrane depolarization. J Cell Physiol 2007; 210:819-30. [PMID: 17146758 DOI: 10.1002/jcp.20902] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Skeletal muscle is a highly plastic tissue with a remarkable capacity to adapt itself to challenges imposed by contractile activity. Adaptive response, that include hypertrophy and activation of oxidative mechanisms have been associated with transient changes in transcriptional activity of specific genes. To define the set of genes regulated by a depolarizing stimulus, we used 22 K mouse oligonucleotide microarrays. Total RNA from C2C12 myotubes was obtained at 2, 4, 18, and 24 h after high K+ stimulation. cDNA from control and depolarized samples was labeled with cyanine 3 or 5 dyes prior to microarray hybridization. Loess normalization followed by statistical analysis resulted in 423 differentially expressed genes using an unadjusted P-value < or = 0.01 as cut off. Depolarization affects transcriptional activity of a limited number of genes, mainly associated with metabolism, cell communication and response to stress. A number of genes related to Ca2+ signaling pathways are induced at 4 h, reinforcing the potential role of Ca2+ in early steps of signal transduction that leads to gene expression. Significant changes in the expression of molecules involved in muscle cell structure were observed; K+-depolarization increased Tnni1 and Acta1 mRNA levels in both differentiated C2C12 and rat skeletal muscle cells in primary culture. Of these two, depolarization induced slow Ca2+ transients appear to have a role only in the regulation of Tnni1 transcriptional activity. We suggest that depolarization induced expression of a small set of genes may underlie Ca2+ dependent plasticity of skeletal muscle cells.
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Affiliation(s)
- Nevenka Juretić
- Centro de Estudios Moleculares de la Célula, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
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Trenerry MK, Carey KA, Ward AC, Cameron-Smith D. STAT3 signaling is activated in human skeletal muscle following acute resistance exercise. J Appl Physiol (1985) 2007; 102:1483-9. [PMID: 17204573 DOI: 10.1152/japplphysiol.01147.2006] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The transcription factor signal transducer and activator of transcription 3 (STAT3) has been identified as a mediator of cytokine signaling and implicated in hypertrophy; however, the importance of this pathway following resistance exercise in human skeletal muscle has not been investigated. In the present study, the phosphorylation and nuclear localization of STAT3, together with STAT3-regulated genes, were measured in the early recovery period following intense resistance exercise. Muscle biopsy samples from healthy subjects (7 males, 23.0 + 0.9 yr) were harvested before and again at 2, 4, and 24 h into recovery following a single bout of maximal leg extension exercise (3 sets, 12 repetitions). Rapid and transient activation of phosphorylated (tyrosine 705) STAT3 was observed at 2 h postexercise. STAT3 phosphorylation paralleled the transient localization of STAT3 to the nucleus, which also peaked at 2 h postexercise. Downstream transcriptional events regulated by STAT3 activation peaked at 2 h postexercise, including early responsive genes c-FOS (800-fold), JUNB (38-fold), and c-MYC (140-fold) at 2 h postexercise. A delayed peak in VEGF (4-fold) was measured 4 h postexercise. Finally, genes associated with modulating STAT3 signaling were also increased following exercise, including the negative regulator SOCS3 (60-fold). Thus, following a single bout of intense resistance exercise, a rapid phosphorylation and nuclear translocation of STAT3 are evident in human skeletal muscle. These data suggest that STAT3 signaling is an important common element and may contribute to the remodeling and adaptation of skeletal muscle following resistance exercise.
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Affiliation(s)
- Marissa K Trenerry
- School of Exercise and Nutrition Science, Deakin University, Burwood, Victoria, Australia
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Choi S, Liu X, Li P, Akimoto T, Lee SY, Zhang M, Yan Z. Transcriptional profiling in mouse skeletal muscle following a single bout of voluntary running: evidence of increased cell proliferation. J Appl Physiol (1985) 2005; 99:2406-15. [PMID: 16081620 DOI: 10.1152/japplphysiol.00545.2005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Skeletal muscle undergoes adaptation following repetitive bouts of exercise. We hypothesize that transcriptional reprogramming and cellular remodeling start in the early phase of long-term training and play an important role in skeletal muscle adaptation. The aim of this study was to define the global mRNA expression in mouse plantaris muscle during (run for 3 and 12 h) and after (3, 6, 12, and 24 h postexercise) a single bout of voluntary running and compare it with that after long-term training (4 wk of running). Among 15,832 gene elements surveyed in a high-density cDNA microarray analysis, 900 showed more than twofold changes at one or more time points. K-means clustering and cumulative hypergeometric probability distribution analyses revealed a significant enrichment of genes involved in defense, cell cycle, cell adhesion and motility, signal transduction, and apoptosis, with induced expression patterns sharing similar patterns with that of peroxisome proliferator activator receptor-gamma coactivator-1alpha and vascular endothelial growth factor A. We focused on the finding of a delayed (at 24 h postexercise) induction of mRNA expression of cell cycle genes origin recognition complex 1, cyclin A2, and cell division 2 homolog A (Schizoccharomyces pombe) and confirmed increased cell proliferation by in vivo 5-bromo-2'-deoxyuridine labeling following voluntary running. X-ray irradiation of the hindlimb significantly diminished exercise-induced 5-bromo-2'-deoxyuridine incorporation. These findings suggest that a single bout of voluntary running activates the transcriptional network and promotes adaptive processes in skeletal muscle, including cell proliferation.
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Affiliation(s)
- Sangdun Choi
- Division of Biology, California Institute of Technology, Pasadena, CA, USA
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Lee JG, Dahi S, Mahimkar R, Tulloch NL, Alfonso-Jaume MA, Lovett DH, Sarkar R. Intronic regulation of matrix metalloproteinase-2 revealed by in vivo transcriptional analysis in ischemia. Proc Natl Acad Sci U S A 2005; 102:16345-50. [PMID: 16258061 PMCID: PMC1283457 DOI: 10.1073/pnas.0508085102] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Matrix metalloproteinase-2 (MMP-2) plays an essential role in angiogenesis and arteriogenesis, two processes critical to restoration of tissue perfusion after ischemia. MMP-2 expression is increased in tissue ischemia, but the responsible mechanisms remain unknown. We studied the transcriptional activation of the MMP-2 gene in a model of hindlimb ischemia by using various MMP-2-lacZ reporter mice and chromatin immunoprecipitation. MMP-2 activity and mRNA were increased after hindlimb ischemia. Mice with targeted deletion of MMP-2 had impaired restoration of perfusion and a high incidence of limb gangrene, indicating that MMP-2 plays a critical role in ischemia-induced revascularization. Ischemia induced the expression and binding of c-Fos, c-Jun, JunB, FosB, and Fra2 to a noncanonical activating protein-1 (AP-1) site present in the MMP-2 promoter and decreased binding of the transcriptional repressor JunD. Ischemia also activated the expression and binding of p53 to an adjacent enhancer site (RE-1) and increased expression and binding of nuclear factor of activated T-cells-c2 to consensus sequences within the first intron. Deletion of either the 5' AP-1/RE-1 region of the promoter or substitution of the first intron abolished ischemia-induced MMP-2 transcription in vivo. Thus, AP-1 transcription factors and intronic activation by nuclear factor of activated T-cells-c2 act in concert to drive ischemia-induced MMP-2 transcription. These findings define a critical role for MMP-2 in ischemia-induced revascularization and identify both previously uncharacterized regulatory elements within the MMP-2 gene and the cognate transcription factors required for MMP-2 activation in vivo after tissue ischemia.
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Affiliation(s)
- Jackie G Lee
- Division of Vascular Surgery, San Francisco Veterans Affairs Medical Center, and Pacific Vascular Research Laboratory, University of California, San Francisco, CA 94121, USA
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Benoyahu D, Akavia UD, Socher R, Shur I. Gene expression in skeletal tissues: application of laser capture microdissection. J Microsc 2005; 220:1-8. [PMID: 16269058 DOI: 10.1111/j.1365-2818.2005.01511.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tissue differentiation is based on the expression of transcription factors, receptors for cytokines, and nuclear receptors that regulate a specific phenotype. The purpose of this study was to select cells from various skeletal tissues in order to analyse differential gene expression of cells in the native environment in vivo. It is a difficult task to obtain cells from skeletal tissues, such as cartilage, periost, bone and muscle, that are structured together and do not exist as individual organs. We used laser capture microdissection which permits the selection and isolation of individual cells from tissue sections. The RNA isolated from these tissues was used for reverse transcriptase-polymerase chain reactions for molecular analysis. We analysed the expression of transcription factors (cFOS, cbfa1, MyoD), receptors for cytokines, nuclear receptors, alkaline phosphatase and the structural proteins osteocalcin and collagen II. The results obtained demonstrate differential patterns of gene expression according to the tissue arrangement in their native in vivo environment, with reliable interpretation of the functions of the analysed genes in the context of intact skeletal tissue physiology.
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Affiliation(s)
- D Benoyahu
- Department of Cell and Developmental Biology, Sackler School of Medicine, Tel-Aviv University, Israel.
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Flück M, Däpp C, Schmutz S, Wit E, Hoppeler H. Transcriptional profiling of tissue plasticity: role of shifts in gene expression and technical limitations. J Appl Physiol (1985) 2005; 99:397-413. [PMID: 16020435 DOI: 10.1152/japplphysiol.00050.2005] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Reprogramming of gene expression has been recognized as a main instructive modality for the adjustments of tissues to various kinds of stress. The recent application of gene expression profiling has provided a powerful tool to elucidate the molecular pathways underlying such tissue remodeling. However, the biological interpretations of expression profiling results critically depend on normalization of transcript signals to mRNA standards before statistical evaluation. A hypothesis is proposed whereby the “fluctuating nature” of gene expression represents an inherent limitation of the test system used to quantify RNA levels. Misinterpretation of gene expression data occurs when RNA quantities are normalized to a subset of mRNAs that are subject to strong regulation. The contention of contradictory biological outcomes using different RNA-normalization schemes is demonstrated in two models of skeletal muscle plasticity with data from custom-designed microarrays and biochemical and ultrastructural evidence for correspondingly altered RNA content and nucleolar activity. The prevalence of these biological constraints is underlined by a literature survey in different models of tissue plasticity with emphasis on the unique malleability of skeletal muscle. Finally, recommendations on the optimal experimental layout are given to control biological and technical variability in microarray and RT-PCR studies. It is proposed to approach normalization of transcript signals by measuring total RNA and DNA content per sample weight and by correcting for concurrently estimated endogenous standards such as major ribosomal RNAs and spiked RNA and DNA species. This allows for later conversion to diverse tissue-relevant references and should improve the physiological interpretations of phenotypic plasticity.
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Affiliation(s)
- Martin Flück
- Dept. of Anatomy, Baltzerstrasse 2, 3000 Bern 9, Switzerland.
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Yang Y, Creer A, Jemiolo B, Trappe S. Time course of myogenic and metabolic gene expression in response to acute exercise in human skeletal muscle. J Appl Physiol (1985) 2005; 98:1745-52. [PMID: 15618316 DOI: 10.1152/japplphysiol.01185.2004] [Citation(s) in RCA: 206] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to examine the time course activation of select myogenic (MRF4, Myf5, MyoD, myogenin) and metabolic (CD36, CPT1, HKII, and PDK4) genes after an acute bout of resistance (RE) or run (Run) exercise. Six RE subjects [25 ± 4 yr (mean ± SD), 74 ± 14 kg, 1.71 ± 0.11 m] and six Run subjects (25 ± 4 yr, 72 ± 5 kg, 1.81 ± 0.07 m, 63 ± 8 ml·kg−1·min−1) were studied. Eight muscle biopsies were taken from the vastus lateralis (RE) and gastrocnemius (Run) before, immediately after, and 1, 2, 4, 8, 12 and 24 h after exercise. RE increased mRNA of MRF4 (3.7- to 4.5-fold 2–4 h post), MyoD (5.8-fold 8 h post), myogenin (2.6- and 3.5-fold 8–12 h post), HKII (3.6- to 10.5-fold 2–12 h post), and PDK4 (14- to 26-fold 2–8 h post). There were no differences in Myf5, CD36, and CPT1 mRNA levels 0–24 h post-RE. Run increased mRNA of MyoD (5.0- to 8.0-fold), HKII (12- to 16-fold), and PDK4 (32- to 52-fold) at 8–12 h postexercise. There were no differences in MRF4, Myf5, myogenin, CD36 and CPT1 mRNA levels 0–24 h post-Run. These data indicate a myogenic and metabolic gene induction with RE and Run exercise. The timing of the gene induction is variable and generally peaks 4–8 h postexercise with all gene expression not significantly different from the preexercise levels by 24 h postexercise. These data provide basic information for the timing of human muscle biopsy samples for gene-expression studies involving exercise.
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Affiliation(s)
- Yifan Yang
- Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA
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Lopez C, Métral S, Eladari D, Drevensek S, Gane P, Chambrey R, Bennett V, Cartron JP, Le Van Kim C, Colin Y. The ammonium transporter RhBG: requirement of a tyrosine-based signal and ankyrin-G for basolateral targeting and membrane anchorage in polarized kidney epithelial cells. J Biol Chem 2004; 280:8221-8. [PMID: 15611082 DOI: 10.1074/jbc.m413351200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RhBG is a nonerythroid member of the Rhesus (Rh) protein family, mainly expressed in the kidney and belonging to the Amt/Mep/Rh superfamily of ammonium transporters. The epithelial expression of renal RhBG is restricted to the basolateral membrane of the connecting tubule and collecting duct cells. We report here that sorting and anchoring of RhBG to the basolateral plasma membrane require a cis-tyrosine-based signal and an association with ankyrin-G, respectively. First, we show by using a model of polarized epithelial Madin-Darby canine kidney cells that the targeting of transfected RhBG depends on a YED motif localized in the cytoplasmic C terminus of the protein. Second, we reveal by yeast two-hybrid analysis a direct interaction between an FLD determinant in the cytoplasmic C-terminal tail of RhBG and the third and fourth repeat domains of ankyrin-G. The biological relevance of this interaction is supported by two observations. (i) RhBG and ankyrin-G were colocalized in vivo in the basolateral domain of epithelial cells from the distal nephron by immunohistochemistry on kidney sections. (ii) The disruption of the FLD-binding motif impaired the membrane expression of RhBG leading to retention on cytoplasmic structures in transfected Madin-Darby canine kidney cells. Mutation of both targeting signal and ankyrin-G-binding site resulted in the same cell surface but nonpolarized expression pattern as observed for the protein mutated on the targeting signal alone, suggesting the existence of a close relationship between sorting and anchoring of RhBG to the basolateral domain of epithelial cells.
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Affiliation(s)
- Claude Lopez
- INSERM, U665, Institut National de la Transfusion Sanguine, Paris F-75015, France
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Irrcher I, Hood DA. Regulation of Egr-1, SRF, and Sp1 mRNA expression in contracting skeletal muscle cells. J Appl Physiol (1985) 2004; 97:2207-13. [PMID: 15310743 DOI: 10.1152/japplphysiol.00388.2004] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The early cellular signals associated with contractile activity initiate the activation and induction of transcription factors that regulate changes in skeletal muscle phenotype. The transcription factors Egr-1, Sp1, and serum response factor (SRF) are potentially important mediators of mitochondrial biogenesis based on the prevalence of binding sites for them in the promoter regions of genes encoding mitochondrial proteins, including PGC-1α, the important regulator of mitochondrial biogenesis. Thus, to further define a role for transcription factors at the onset of contractile activity, we examined the time-dependent alterations in Egr-1, Sp1, and SRF mRNA and the levels in electrically stimulated mouse C2C12skeletal muscle cells. Early transient increases in Egr-1 mRNA levels within 30 min ( P < 0.05) of contractile activity led to threefold increases ( P < 0.05) in Egr-1 protein by 60 min. The increase in Egr-1 mRNA was not because of increased stability, as Egr-1 mRNA half-life after 30 min of stimulation showed only a 58% decline. Stimulation of muscle cells had no effect on Sp1 mRNA but led to progressive increases ( P < 0.05) in SRF mRNA by 30 and 60 min. This was not matched by increases in SRF protein but occurred coincident with increases ( P < 0.05) in SRF-serum response element DNA binding at 30 and 60 min as a result of SRF phosphorylation on serine-103. To assess the importance of the recovery period, 12 h of continuous contractile activity was compared with four successive 3-h bouts, with an intervening 21-h recovery period after each bout. Continuous contractile activity led to a twofold increase ( P < 0.05) in Egr-1 mRNA, no change in SRF mRNA, and a 43% decrease in Sp1 mRNA expression. The recovery period prevented the decline in Sp1 mRNA, produced a decrease in Egr-1 mRNA, and had no effect on SRF mRNA. Thus continuous and intermittent contractile activity evoked different specific transcription factor expression patterns, which may ultimately contribute to divergent qualitative, or temporal patterns of, phenotypic adaptation in muscle.
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Affiliation(s)
- Isabella Irrcher
- Dept. of Kinesiology and Health Science, York University, Toronto, Ontario, Canada M3J 1P3
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46
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Myburgh KH. What makes an endurance athlete world-class? Not simply a physiological conundrum. Comp Biochem Physiol A Mol Integr Physiol 2004; 136:171-90. [PMID: 14527639 DOI: 10.1016/s1095-6433(03)00220-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inter-individual variation in endurance performance capacity is a characteristic, not only of the general population, but also in trained athletes. The ability of sport scientists to predict which athletes amongst an elite group will become world-class is limited. We do not fully understand the interactions between biological factors, training, recovery and competitive performance. Assessment methods and interpretation of results do not take into account the facts that most research is not done on elite athletes and performances of world-class endurance athletes cannot be attributed to aerobic capacity alone. Many lines of evidence suggest that there is a limit to adaptation in aerobic capacity. Recent advances in molecular biology and genetics should be harnessed by exercise biologists in conjunction with previously used physiological, histological and biochemical techniques to study elite athletes and their responses to different training and recovery regimens. Technological advances should be harnessed to study world-class athletes to determine optimal training and competition strategies. In summary, it is likely that multiple factors are essential contributors to world-class endurance performance and that it is only by using a multidisciplinary approach that we will come closer to solving the conundrum: 'What makes an endurance athlete world class?'
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Affiliation(s)
- Kathryn H Myburgh
- Department of Physiological Sciences, University of Stellenbosch, Stellenbosch, Private Bag X1, 7602, Matieland, South Africa.
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Wittwer M, Billeter R, Hoppeler H, Flück M. Regulatory gene expression in skeletal muscle of highly endurance-trained humans. ACTA ACUST UNITED AC 2004; 180:217-27. [PMID: 14738480 DOI: 10.1046/j.0001-6772.2003.01242.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM AND BACKGROUND Changes in regulatory and structural gene expression provide the molecular basis for the adaptation of human skeletal muscle to endurance exercise. HYPOTHESIS The steady-state levels of multiple mRNAs mainly involved in regulatory functions differ between highly endurance-trained and untrained subjects in a muscle heavily recruited during the exercise. METHODS Biopsies from musculus vastus lateralis of seven untrained (UT) subjects [maximal oxygen consumption (VO2max) = 39 mL kg-1 min-1] and seven trained (T) professional cyclists (VO2max = 72 mL kg-1 min-1) were analysed for the contents of 597 different mRNAs using commercially available cDNA arrays (Clontech no. 7740-1). Intra-individual expression profiles were compared by least-square linear regression analysis. Differences in gene expression between the two groups were tested for statistical significance using L1 regression analysis combined with the sign test on all permutations of scatter plots of log raw values from UT vs. T subjects. RESULTS Transcripts for 144 of 597 genes were sufficiently abundant to be analysed quantitatively. The expression profiles of the T group had a better intragroup correlation (R2) than those of the UT group (0.78 vs. 0.65, P < 0.05). An intergroup (T vs. UT) correlation of expression profiles gave an R2 of 0.71. Statistical analysis at a false discovery rate of 5% identified differential expression of nine cell-regulatory genes between T and UT. The mRNA levels of eight genes, including two DNA repair enzymes, transcription factors, signal transducers, a glycolytic enzyme and a factor involved in steroid hormone metabolism were increased in T vs. UT. Conversely, the mRNA of the tumour suppressor APC was downregulated with endurance training. Selective reverse-transcriptase polymerase chain reaction experiments confirmed the signal estimates from the array analysis. CONCLUSIONS The repetitive impact of the complex exercise stimuli in professional cyclists attenuated the interindividual differences in regulatory gene expression in skeletal muscle. Long-term nuclear reprogramming of regulatory gene expression seems to be characteristic of human musculus vastus lateralis in a highly endurance-trained steady state.
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Affiliation(s)
- M Wittwer
- Department of Anatomy, University of Bern, Bern, Switzerland
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48
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Chen YW, Hubal MJ, Hoffman EP, Thompson PD, Clarkson PM. Molecular responses of human muscle to eccentric exercise. J Appl Physiol (1985) 2003; 95:2485-94. [PMID: 12937035 DOI: 10.1152/japplphysiol.01161.2002] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We examined the effect of eccentric exercise on the transcriptome of skeletal muscle in three male human volunteers who performed 300 concentric contractions with one leg and 300 eccentric contractions with the opposite leg. Vastus lateralis muscle biopsies were taken from both legs at 4-8 h after exercise, and expression was profiled by using 12000 gene Affymetrix U95Av2 microarrays. We found a high concordance of expression responses to eccentric contractions between our human and rat data from a previous study (Chen YW, Nader GA, Baar KR, Fedele MJ, Hoffman EP, and Esser KA. J Physiol 545: 27-41, 2002) ( approximately 50% of gene expression changes shared between species). Potential human-specific changes included greater inflammatory responses [chemokine (C-C motif) ligand 2, C/EBP delta, and IL-1 receptor] and vascular remodeling (tenascin C and lipocortin II). Induction of c-fos and lipocortin II were confirmed at the protein level, with c-fos localized to myofiber nuclei and lipocortin II to intramuscular capillaries. We also confirmed the eccentric-induced expression of six transcripts by quantitative RT-PCR (cardiac ankyrin-repeated protein, chemokine ligand 2, CCAAT/enhancer binding protein delta, IL-1 receptor, tenascin C, and cysteine-rich angiogenic inducer 61). These data provide the first characterization of the transcriptional response of skeletal muscle to eccentric exercise in humans and represent a preliminary step in understanding the molecular processes underlying muscle remodeling (including a new focus on rapid changes in the capillary bed) and inflammatory responses after damaging lengthening contractions.
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Affiliation(s)
- Yi-Wen Chen
- Center for Genetic Medicine, Children's National Medical Center, George Washington University, Washington, DC 20010, USA
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Dupont-Versteegden EE, Houlé JD, Dennis RA, Zhang J, Knox M, Wagoner G, Peterson CA. Exercise-induced gene expression in soleus muscle is dependent on time after spinal cord injury in rats. Muscle Nerve 2003; 29:73-81. [PMID: 14694501 DOI: 10.1002/mus.10511] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Cycling exercise attenuates atrophy in hindlimb muscles and causes changes in spinal cord properties after spinal cord injury in rats. We hypothesized that exercising soleus muscle expresses genes that are potentially beneficial to the injured spinal cord. Rats underwent spinal cord injury at T10 and were exercised on a motor-driven bicycle. Soleus muscle and lumbar spinal cord tissue were used for messenger RNA (mRNA) analysis. Gene expression of brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) was elevated 11- and 14-fold, respectively, in soleus muscle after one bout of exercise performed 5 days after spinal cord transection. Also, c-fos and heat shock protein-27 (HSP27) mRNA abundance were increased 11- and 7-fold, respectively. When exercise was started 2 days after the injury, the changes in gene expression were not observed. By contrast, at 2 but not at 5 days after transection, expression of the HSP27 gene was elevated sixfold in the lumbar spinal cord, independent of exercise. Electromyographic activity in soleus muscles was also decreased at 2 days, indicating that the spinal cord was less permissive to exercise at this early time. Long-term exercise for 4 weeks attenuated muscle atrophy equally well in rats started at 2 days or 5 days after injury. We conclude that BDNF and GDNF released from exercising muscle may be involved in exercise-induced plasticity of the spinal cord. Furthermore, the data suggest that the lumbar spinal cord undergoes time-dependent changes that temporarily impede the ability of the muscle to respond to exercise.
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Affiliation(s)
- Esther E Dupont-Versteegden
- Department of Geriatrics, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, Arkansas 72205, USA.
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Lencesova L, O'Neill A, Resneck WG, Bloch RJ, Blaustein MP. Plasma membrane-cytoskeleton-endoplasmic reticulum complexes in neurons and astrocytes. J Biol Chem 2003; 279:2885-93. [PMID: 14593108 DOI: 10.1074/jbc.m310365200] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The possibility that certain integral plasma membrane (PM) proteins involved in Ca(2+) homeostasis form junctional units with adjacent endoplasmic reticulum (ER) in neurons and glia was explored using immunoprecipitation and immunocytochemistry. Rat brain membranes were solubilized with the mild, non-ionic detergent, IGEPAL CA-630. Na(+)/Ca(2+) exchanger type 1 (NCX1), a key PM Ca(2+) transporter, was immunoprecipitated from the detergent-soluble fraction. Several abundant PM proteins co-immunoprecipitated with NCX1, including the alpha2 and alpha3 isoforms of the Na(+) pump catalytic (alpha) subunit, and the alpha2 subunit of the dihydropyridine receptor. The adaptor protein, ankyrin 2 (Ank 2), and the cytoskeletal proteins, alpha-fodrin and beta-spectrin, also selectively co-immunoprecipitated with NCX1, as did the ER proteins, Ca(2+) pump type 2 (SERCA 2), and inositol-trisphosphate receptor type 1 (IP(3)R-1). In contrast, a number of other abundant PMs, adaptors, and cytoskeletal proteins did not co-immunoprecipitate with NCX1, including the Na(+) pump alpha1 isoform, PM Ca(2+) pump type 1 (PMCA1), beta-fodrin, and Ank 3. In reciprocal experiments, immunoprecipitation with antibodies to the Na(+) pump alpha2 and alpha3 isoforms, but not alpha1, co-immunoprecipitated NCX1; the antibodies to alpha1 did, however, co-immunoprecipitate PMCA1. Antibodies to Ank 2, alpha-fodrin, beta-spectrin and IP(3)R-1 all co-immunoprecipitated NCX1. Immunocytochemistry revealed partial co-localization of beta-spectrin with NCX1, Na(+) pump alpha3, and IP(3)R-1 in neurons and of alpha-fodrin with NCX1 and SERCA2 in astrocytes. The data support the idea that in neurons and glia PM microdomains containing NCX1 and Na(+) pumps with alpha2 or alpha3 subunits form Ca(2+) signaling complexes with underlying ER containing SERCA2 and IP(3)R-1. These PM and ER components appear to be linked through the cytoskeletal spectrin network, to which they are probably tethered by Ank 2.
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Affiliation(s)
- Lubomira Lencesova
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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