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Cui M, Jannig P, Halladjian M, Figueiredo VC, Wen Y, Vechetti IJ, Krogh N, Jude B, Edman S, Lanner J, McCarthy J, Murach KA, Sejersen T, Nielsen H, von Walden F. The rRNA epitranscriptome and myonuclear SNORD landscape in skeletal muscle fibers contributes to ribosome heterogeneity and is altered by a hypertrophic stimulus. Am J Physiol Cell Physiol 2024; 327:C516-C524. [PMID: 38912733 PMCID: PMC11426995 DOI: 10.1152/ajpcell.00301.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/03/2024] [Accepted: 06/03/2024] [Indexed: 06/25/2024]
Abstract
In cell biology, ribosomal RNA (rRNA) 2'O-methyl (2'-O-Me) is the most prevalent posttranscriptional chemical modification contributing to ribosome heterogeneity. The modification involves a family of small nucleolar RNAs (snoRNAs) and is specified by box C/D snoRNAs (SNORDs). Given the importance of ribosome biogenesis for skeletal muscle growth, we asked if rRNA 2'-O-Me in nascent ribosomes synthesized in response to a growth stimulus is an unrecognized mode of ribosome heterogeneity in muscle. To determine the pattern and dynamics of 2'-O-Me rRNA, we used a sequencing-based profiling method called RiboMeth-seq (RMS). We applied this method to tissue-derived rRNA of skeletal muscle and rRNA specifically from the muscle fiber using an inducible myofiber-specific RiboTag mouse in sedentary and mechanically overloaded conditions. These analyses were complemented by myonuclear-specific small RNA sequencing to profile SNORDs and link the rRNA epitranscriptome to known regulatory elements generated within the muscle fiber. We demonstrate for the first time that mechanical overload of skeletal muscle 1) induces decreased 2'-O-Me at a subset of skeletal muscle rRNA and 2) alters the SNORD profile in isolated myonuclei. These findings point to a transient diversification of the ribosome pool via 2'-O-Me during growth and adaptation in skeletal muscle. These findings suggest changes in ribosome heterogeneity at the 2'-O-Me level during muscle hypertrophy and lay the foundation for studies investigating the functional implications of these newly identified "growth-induced" ribosomes.NEW & NOTEWORTHY Ribosomal RNAs (rRNAs) are posttranscriptionally modified by 2'O-methyl (2'-O-Me). This study applied RiboMeth-seq (RMS) to detect changes in 2'-O-Me levels during skeletal muscle hypertrophy, uncovering transient diversification of the ribosome pool in skeletal muscle fibers. This work implies a role for ribosome heterogeneity in skeletal muscle growth and adaptation.
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Affiliation(s)
- Minying Cui
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Paulo Jannig
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Maral Halladjian
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Vandré C Figueiredo
- Department of Biological Sciences, Oakland University, Rochester, Michigan, United States
| | - Yuan Wen
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
- Division of Biomedical Informatics, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
| | - Ivan J Vechetti
- Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, United States
| | - Nicolai Krogh
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Baptiste Jude
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Sebastian Edman
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Johanna Lanner
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - John McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Kevin A Murach
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
| | - Thomas Sejersen
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
- Department of Child Neurology, Karolinska University Hospital, Astrid Lindgren Children's Hospital, Stockholm, Sweden
- Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Hong Kong, People's Republic of China
| | - Henrik Nielsen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Ferdinand von Walden
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
- Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Hong Kong, People's Republic of China
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2
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Burke BI, Ismaeel A, McCarthy JJ. The utility of the rodent synergist ablation model in identifying molecular and cellular mechanisms of skeletal muscle hypertrophy. Am J Physiol Cell Physiol 2024; 327:C601-C606. [PMID: 39069822 PMCID: PMC11427019 DOI: 10.1152/ajpcell.00362.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 06/16/2024] [Accepted: 06/17/2024] [Indexed: 07/30/2024]
Abstract
Skeletal muscle exhibits remarkable plasticity to adapt to stimuli such as mechanical loading. The mechanisms that regulate skeletal muscle hypertrophy due to mechanical overload have been thoroughly studied. Remarkably, our understanding of many of the molecular and cellular mechanisms that regulate hypertrophic growth were first identified using the rodent synergist ablation (SA) model and subsequently corroborated in human resistance exercise training studies. To demonstrate the utility of the SA model, we briefly summarize the hypertrophic mechanisms identified using the model and the following translation of these mechanism to human skeletal muscle hypertrophy induced by resistance exercise training.
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Affiliation(s)
- Benjamin I Burke
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Ahmed Ismaeel
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
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3
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Burke BI, Ismaeel A, von Walden F, Murach KA, McCarthy JJ. Skeletal muscle hypertrophy: cell growth is cell growth. Am J Physiol Cell Physiol 2024; 327:C614-C618. [PMID: 39069829 DOI: 10.1152/ajpcell.00418.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Accepted: 07/05/2024] [Indexed: 07/30/2024]
Abstract
Roberts et al. have provided an insightful counterpoint to our review article on the utility of the synergist ablation model. The purpose of this review is to provide some further dialogue regarding the strengths and weaknesses of the synergist ablation model. Specifically, we highlight that the robustness of the model overshadows surgical limitations. We also compare the transcriptomic responses to synergist ablation in mice and resistance exercise in humans to identify common pathways. We conclude that "cell growth is cell growth" and that the mechanisms available to cells to accumulate biomass and increase in size are similar across cell types and independent of the rate of growth.
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Affiliation(s)
- Benjamin I Burke
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Ahmed Ismaeel
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
| | - Ferdinand von Walden
- Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Kevin A Murach
- Department Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas, United States
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, United States
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4
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Ismaeel A, Peck BD, Montgomery MM, Burke BI, Goh J, Kang G, Franco AB, Xia Q, Goljanek-Whysall K, McDonagh B, McLendon JM, Koopmans PJ, Jacko D, Schaaf K, Bloch W, Gehlert S, Wen Y, Murach KA, Peterson CA, Boudreau RL, Fisher-Wellman KH, McCarthy JJ. microRNA-1 Regulates Metabolic Flexibility in Skeletal Muscle via Pyruvate Metabolism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.09.607377. [PMID: 39149347 PMCID: PMC11326265 DOI: 10.1101/2024.08.09.607377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
MicroRNA-1 (miR-1) is the most abundant miRNA in adult skeletal muscle. To determine the function of miR-1 in adult skeletal muscle, we generated an inducible, skeletal muscle-specific miR-1 knockout (KO) mouse. Integration of RNA-sequencing (RNA-seq) data from miR-1 KO muscle with Argonaute 2 enhanced crosslinking and immunoprecipitation sequencing (AGO2 eCLIP-seq) from human skeletal muscle identified miR-1 target genes involved with glycolysis and pyruvate metabolism. The loss of miR-1 in skeletal muscle induced cancer-like metabolic reprogramming, as shown by higher pyruvate kinase muscle isozyme M2 (PKM2) protein levels, which promoted glycolysis. Comprehensive bioenergetic and metabolic phenotyping combined with skeletal muscle proteomics and metabolomics further demonstrated that miR-1 KO induced metabolic inflexibility as a result of pyruvate oxidation resistance. While the genetic loss of miR-1 reduced endurance exercise performance in mice and in C. elegans, the physiological down-regulation of miR-1 expression in response to a hypertrophic stimulus in both humans and mice causes a similar metabolic reprogramming that supports muscle cell growth. Taken together, these data identify a novel post-translational mechanism of adult skeletal muscle metabolism regulation mediated by miR-1.
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Affiliation(s)
- Ahmed Ismaeel
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Bailey D Peck
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - McLane M Montgomery
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - Benjamin I Burke
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Jensen Goh
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Gyumin Kang
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
- Division of Biomedical Informatics, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Abigail B Franco
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Mass Spectrometry and Proteomics Core, University of Kentucky, Lexington, KY, USA
| | - Qin Xia
- Discipline of Physiology, School of Medicine, College of Medicine, Nursing, and Health Sciences, University of Galway, Galway, Ireland
| | - Katarzyna Goljanek-Whysall
- Discipline of Physiology, School of Medicine, College of Medicine, Nursing, and Health Sciences, University of Galway, Galway, Ireland
| | - Brian McDonagh
- Discipline of Physiology, School of Medicine, College of Medicine, Nursing, and Health Sciences, University of Galway, Galway, Ireland
| | - Jared M McLendon
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA, United States
| | - Pieter J Koopmans
- Department Health, Human Performance, & Recreation, University of Arkansas, Fayetteville, AR, USA
- Cell and Molecular Biology Graduate Program, University of Arkansas, Fayetteville, AR, USA
| | - Daniel Jacko
- Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
- Olympic Base Center, North Rhine-Westphalia/Rhineland, Cologne, Germany
| | - Kirill Schaaf
- Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
- Olympic Base Center, North Rhine-Westphalia/Rhineland, Cologne, Germany
| | - Wilhelm Bloch
- Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
| | - Sebastian Gehlert
- Institute of Cardiovascular Research and Sports Medicine, German Sport University, Cologne, Germany
- Department for the Biosciences of Sports, Institute of Sports Science, University of Hildesheim, Hildesheim, Germany
| | - Yuan Wen
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
- Division of Biomedical Informatics, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Kevin A Murach
- Department Health, Human Performance, & Recreation, University of Arkansas, Fayetteville, AR, USA
- Cell and Molecular Biology Graduate Program, University of Arkansas, Fayetteville, AR, USA
| | - Charlotte A Peterson
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
| | - Ryan L Boudreau
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Kelsey H Fisher-Wellman
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, USA
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, USA
- Center for Muscle Biology, College of Health Sciences, University of Kentucky, Lexington, KY, USA
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5
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Korb A, Tajbakhsh S, Comai GE. Functional specialisation and coordination of myonuclei. Biol Rev Camb Philos Soc 2024; 99:1164-1195. [PMID: 38477382 DOI: 10.1111/brv.13063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 01/30/2024] [Accepted: 02/02/2024] [Indexed: 03/14/2024]
Abstract
Myofibres serve as the functional unit for locomotion, with the sarcomere as fundamental subunit. Running the entire length of this structure are hundreds of myonuclei, located at the periphery of the myofibre, juxtaposed to the plasma membrane. Myonuclear specialisation and clustering at the centre and ends of the fibre are known to be essential for muscle contraction, yet the molecular basis of this regionalisation has remained unclear. While the 'myonuclear domain hypothesis' helped explain how myonuclei can independently govern large cytoplasmic territories, novel technologies have provided granularity on the diverse transcriptional programs running simultaneously within the syncytia and added a new perspective on how myonuclei communicate. Building upon this, we explore the critical cellular and molecular sources of transcriptional and functional heterogeneity within myofibres, discussing the impact of intrinsic and extrinsic factors on myonuclear programs. This knowledge provides new insights for understanding muscle development, repair, and disease, but also opens avenues for the development of novel and precise therapeutic approaches.
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Affiliation(s)
- Amaury Korb
- Institut Pasteur, Université Paris Cité, CNRS UMR 3738, Stem Cells & Development Unit, 25 rue du Dr. Roux, Institut Pasteur, Paris, F-75015, France
| | - Shahragim Tajbakhsh
- Institut Pasteur, Université Paris Cité, CNRS UMR 3738, Stem Cells & Development Unit, 25 rue du Dr. Roux, Institut Pasteur, Paris, F-75015, France
| | - Glenda E Comai
- Institut Pasteur, Université Paris Cité, CNRS UMR 3738, Stem Cells & Development Unit, 25 rue du Dr. Roux, Institut Pasteur, Paris, F-75015, France
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6
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Chambers TL, Dimet-Wiley A, Keeble AR, Haghani A, Lo WJ, Kang G, Brooke R, Horvath S, Fry CS, Watowich SJ, Wen Y, Murach KA. Methylome-proteome integration after late-life voluntary exercise training reveals regulation and target information for improved skeletal muscle health. J Physiol 2024. [PMID: 39058663 DOI: 10.1113/jp286681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/02/2024] [Indexed: 07/28/2024] Open
Abstract
Exercise is a potent stimulus for combatting skeletal muscle ageing. To study the effects of exercise on muscle in a preclinical setting, we developed a combined endurance-resistance training stimulus for mice called progressive weighted wheel running (PoWeR). PoWeR improves molecular, biochemical, cellular and functional characteristics of skeletal muscle and promotes aspects of partial epigenetic reprogramming when performed late in life (22-24 months of age). In this investigation, we leveraged pan-mammalian DNA methylome arrays and tandem mass-spectrometry proteomics in skeletal muscle to provide detailed information on late-life PoWeR adaptations in female mice relative to age-matched sedentary controls (n = 7-10 per group). Differential CpG methylation at conserved promoter sites was related to transcriptional regulation genes as well as Nr4a3, Hes1 and Hox genes after PoWeR. Using a holistic method of -omics integration called binding and expression target analysis (BETA), methylome changes were associated with upregulated proteins related to global and mitochondrial translation after PoWeR (P = 0.03). Specifically, BETA implicated methylation control of ribosomal, mitoribosomal, and mitochondrial complex I protein abundance after training. DNA methylation may also influence LACTB, MIB1 and UBR4 protein induction with exercise - all are mechanistically linked to muscle health. Computational cistrome analysis predicted several transcription factors including MYC as regulators of the exercise trained methylome-proteome landscape, corroborating prior late-life PoWeR transcriptome data. Correlating the proteome to muscle mass and fatigue resistance revealed positive relationships with VPS13A and NPL levels, respectively. Our findings expose differential epigenetic and proteomic adaptations associated with translational regulation after PoWeR that could influence skeletal muscle mass and function in aged mice. KEY POINTS: Late-life combined endurance-resistance exercise training from 22-24 months of age in mice is shown to improve molecular, biochemical, cellular and in vivo functional characteristics of skeletal muscle and promote aspects of partial epigenetic reprogramming and epigenetic age mitigation. Integration of DNA CpG 36k methylation arrays using conserved sites (which also contain methylation ageing clock sites) with exploratory proteomics in skeletal muscle extends our prior work and reveals coordinated and widespread regulation of ribosomal, translation initiation, mitochondrial ribosomal (mitoribosomal) and complex I proteins after combined voluntary exercise training in a sizeable cohort of female mice (n = 7-10 per group and analysis). Multi-omics integration predicted epigenetic regulation of serine β-lactamase-like protein (LACTB - linked to tumour resistance in muscle), mind bomb 1 (MIB1 - linked to satellite cell and type 2 fibre maintenance) and ubiquitin protein ligase E3 component N-recognin 4 (UBR4 - linked to muscle protein quality control) after training. Computational cistrome analysis identified MYC as a regulator of the late-life training proteome, in agreement with prior transcriptional analyses. Vacuolar protein sorting 13 homolog A (VPS13A) was positively correlated to muscle mass, and the glycoprotein/glycolipid associated sialylation enzyme N-acetylneuraminate pyruvate lyase (NPL) was associated to in vivo muscle fatigue resistance.
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Affiliation(s)
- Toby L Chambers
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| | | | - Alexander R Keeble
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Amin Haghani
- Department of Human Genetics, University of California Los Angeles, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
| | - Wen-Juo Lo
- Department of Educational Statistics and Research Methods, University of Arkansas, Fayetteville, AR, USA
| | - Gyumin Kang
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, KY, USA
- Division of Biomedical Informatics, Department of Internal Medicine, University of Kentucky, Lexington, KY, USA
| | - Robert Brooke
- Epigenetic Clock Development Foundation, Los Angeles, CA, USA
| | - Steve Horvath
- Department of Human Genetics, University of California Los Angeles, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
- Epigenetic Clock Development Foundation, Los Angeles, CA, USA
| | - Christopher S Fry
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Stanley J Watowich
- Ridgeline Therapeutics, Houston, TX, USA
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Yuan Wen
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- Department of Physiology, University of Kentucky, Lexington, KY, USA
- Division of Biomedical Informatics, Department of Internal Medicine, University of Kentucky, Lexington, KY, USA
| | - Kevin A Murach
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
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7
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Jones RG, von Walden F, Murach KA. Exercise-Induced MYC as an Epigenetic Reprogramming Factor That Combats Skeletal Muscle Aging. Exerc Sport Sci Rev 2024; 52:63-67. [PMID: 38391187 PMCID: PMC10963142 DOI: 10.1249/jes.0000000000000333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Of the "Yamanaka factors" Oct3/4 , Sox2 , Klf4 , and c-Myc (OSKM), the transcription factor c-Myc ( Myc ) is the most responsive to exercise in skeletal muscle and is enriched within the muscle fiber. We hypothesize that the pulsatile induction of MYC protein after bouts of exercise can serve to epigenetically reprogram skeletal muscle toward a more resilient and functional state.
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Affiliation(s)
- Ronald G. Jones
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Ferdinand von Walden
- Neuropediatrics, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Kevin A. Murach
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, USA
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8
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Edman S, Jones RG, Jannig PR, Fernandez-Gonzalo R, Norrbom J, Thomas NT, Khadgi S, Koopmans PJ, Morena F, Peterson CS, Scott LN, Greene NP, Figueiredo VC, Fry CS, Zhengye L, Lanner JT, Wen Y, Alkner B, Murach KA, von Walden F. The 24-Hour Time Course of Integrated Molecular Responses to Resistance Exercise in Human Skeletal Muscle Implicates MYC as a Hypertrophic Regulator That is Sufficient for Growth. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.26.586857. [PMID: 38586026 PMCID: PMC10996609 DOI: 10.1101/2024.03.26.586857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Molecular control of recovery after exercise in muscle is temporally dynamic. A time course of biopsies around resistance exercise (RE) combined with -omics is necessary to better comprehend the molecular contributions of skeletal muscle adaptation in humans. Vastus lateralis biopsies before and 30 minutes, 3-, 8-, and 24-hours after acute RE were collected. A time-point matched biopsy-only group was also included. RNA-sequencing defined the transcriptome while DNA methylomics and computational approaches complemented these data. The post-RE time course revealed: 1) DNA methylome responses at 30 minutes corresponded to upregulated genes at 3 hours, 2) a burst of translation- and transcription-initiation factor-coding transcripts occurred between 3 and 8 hours, 3) global gene expression peaked at 8 hours, 4) ribosome-related genes dominated the mRNA landscape between 8 and 24 hours, 5) methylation-regulated MYC was a highly influential transcription factor throughout the 24-hour recovery and played a primary role in ribosome-related mRNA levels between 8 and 24 hours. The influence of MYC in human muscle adaptation was strengthened by transcriptome information from acute MYC overexpression in mouse muscle. To test whether MYC was sufficient for hypertrophy, we generated a muscle fiber-specific doxycycline inducible model of pulsatile MYC induction. Periodic 48-hour pulses of MYC over 4 weeks resulted in higher muscle mass and fiber size in the soleus of adult female mice. Collectively, we present a temporally resolved resource for understanding molecular adaptations to RE in muscle and reveal MYC as a regulator of RE-induced mRNA levels and hypertrophy.
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Affiliation(s)
- Sebastian Edman
- Karolinska Institute, Division of Pediatric Neurology, Department of Women’s and Children’s Health, Stockholm, Sweden
| | - Ronald G. Jones
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Paulo R. Jannig
- Karolinska Institute, Division of Pediatric Neurology, Department of Women’s and Children’s Health, Stockholm, Sweden
| | - Rodrigo Fernandez-Gonzalo
- Karolinska Institute, Division of Clinical Physiology, Department of Laboratory Medicine, Stockholm, Sweden
- Unit of Clinical Physiology, Karolinska University Hospital, Huddinge, Sweden
| | - Jessica Norrbom
- Karolinska Institute, Molecular Exercise Physiology Group, Department of Physiology and Pharmacology, Stockholm, Sweden
| | - Nicholas T. Thomas
- University of Kentucky, Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Athletic Training and Clinical Nutrition, Lexington, KY, USA
| | - Sabin Khadgi
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Pieter Jan Koopmans
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cell and Molecular Biology Graduate Program, Fayetteville, AR, USA
| | - Francielly Morena
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Calvin S. Peterson
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Logan N. Scott
- University of Kentucky, Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Physiology, Lexington, KY, USA
- University of Kentucky, Department of Internal Medicine, Division of Biomedical Informatics, Lexington, KY, USA
| | - Nicholas P. Greene
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Vandre C. Figueiredo
- University of Kentucky, Center for Muscle Biology, Lexington, KY, USA
- Oakland University, Department of Biological Sciences, Rochester Hills, MI, USA
| | - Christopher S. Fry
- University of Kentucky, Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Athletic Training and Clinical Nutrition, Lexington, KY, USA
| | - Liu Zhengye
- Karolinska Institute, Molecular Muscle Physiology & Pathophysiology Group, Department of Physiology & Pharmacology, Stockholm, Sweden
| | - Johanna T. Lanner
- Karolinska Institute, Molecular Muscle Physiology & Pathophysiology Group, Department of Physiology & Pharmacology, Stockholm, Sweden
| | - Yuan Wen
- University of Kentucky, Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Physiology, Lexington, KY, USA
- University of Kentucky, Department of Internal Medicine, Division of Biomedical Informatics, Lexington, KY, USA
| | - Björn Alkner
- Department of Orthopedics, Eksjö, Region Jönköping County and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Kevin A. Murach
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cell and Molecular Biology Graduate Program, Fayetteville, AR, USA
| | - Ferdinand von Walden
- Karolinska Institute, Division of Pediatric Neurology, Department of Women’s and Children’s Health, Stockholm, Sweden
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Laskin GR, Cabrera AR, Greene NP, Tomko RJ, Vied C, Gordon BS. The mechanosensitive gene arrestin domain containing 2 regulates myotube diameter with direct implications for disuse atrophy with aging. Am J Physiol Cell Physiol 2024; 326:C768-C783. [PMID: 38314723 PMCID: PMC11193484 DOI: 10.1152/ajpcell.00444.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 01/08/2024] [Accepted: 01/22/2024] [Indexed: 02/07/2024]
Abstract
Arrestin domain containing 2 and 3 (Arrdc2/3) are genes whose mRNA contents are decreased in young skeletal muscle following mechanical overload. Arrdc3 is linked to the regulation of signaling pathways in nonmuscle cells that could influence skeletal muscle size. Despite a similar amino acid sequence, Arrdc2 function remains undefined. The purpose of this study was to further explore the relationship of Arrdc2/Arrdc3 expression with changes in mechanical load in young and aged muscle and define the effect of Arrdc2/3 expression on C2C12 myotube diameter. In young and aged mice, mechanical load was decreased using hindlimb suspension whereas mechanical load was increased by reloading previously unloaded muscle or inducing high-force contractions. Arrdc2 and Arrdc3 mRNAs were overexpressed in C2C12 myotubes using adenoviruses. Myotube diameter was determined 48-h posttransfection, and RNA sequencing was performed on those samples. Arrdc2 and Arrdc3 mRNA content was higher in the unloaded muscle within 1 day of disuse and remained higher up through 10 days. The induction of Arrdc2 mRNA was more pronounced in aged muscle than young muscle in response to unloading. Reloading previously unloaded muscle of young and aged mice restored Arrdc2 and Arrdc3 levels to ambulatory levels. Increasing mechanical load beyond normal ambulatory levels lowered Arrdc2 mRNA, but not Arrdc3 mRNA, in young and aged muscle. Arrdc2 overexpression only was sufficient to lower myotube diameter in C2C12 cells in part by altering the transcriptome favoring muscle atrophy. These data are consistent with Arrdc2 contributing to disuse atrophy, particularly in aged muscle.NEW & NOTEWORTHY We establish Arrdc2 as a novel mechanosensitive gene highly induced in response to mechanical unloading, particularly in aged muscle. Arrdc2 induction in C2C12 myotubes is sufficient to produce thinner myotubes and a transcriptional landscape consistent with muscle atrophy and disuse.
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Affiliation(s)
- Grant R Laskin
- Department of of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, United States
| | - Ana Regina Cabrera
- Department of Health, Human Performance and Recreation, Cachexia Research Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
| | - Nicholas P Greene
- Department of Health, Human Performance and Recreation, Cachexia Research Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
| | - Robert J Tomko
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, United States
| | - Cynthia Vied
- Translational Science Laboratory, Florida State University College of Medicine, Tallahassee, Florida, United States
| | - Bradley S Gordon
- Department of of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, United States
- Institute of Sports Sciences and Medicine, Florida State University, Tallahassee, Florida, United States
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10
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Viggars MR, Sutherland H, Cardozo CP, Jarvis JC. Conserved and species-specific transcriptional responses to daily programmed resistance exercise in rat and mouse. FASEB J 2023; 37:e23299. [PMID: 37994729 DOI: 10.1096/fj.202301611r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/19/2023] [Accepted: 10/26/2023] [Indexed: 11/24/2023]
Abstract
Mice are often used in gain or loss of function studies to understand how genes regulate metabolism and adaptation to exercise in skeletal muscle. Once-daily resistance training with electrical nerve stimulation produces hypertrophy of the dorsiflexors in rat, but not in mouse. Using implantable pulse generators, we assessed the acute transcriptional response (1-h post-exercise) after 2, 10, and 20 days of training in free-living mice and rats using identical nerve stimulation paradigms. RNA sequencing revealed strong concordance in the timecourse of many transcriptional responses in the tibialis anterior muscles of both species including responses related to "stress responses/immediate-early genes, and "collagen homeostasis," "ribosomal subunits," "autophagy," and "focal adhesion." However, pathways associated with energy metabolism including "carbon metabolism," "oxidative phosphorylation," "mitochondrial translation," "propanoate metabolism," and "valine, leucine, and isoleucine degradation" were oppositely regulated between species. These pathways were suppressed in the rat but upregulated in the mouse. Our transcriptional analysis suggests that although many pathways associated with growth show remarkable similarities between species, the absence of an actual growth response in the mouse may be because the mouse prioritizes energy metabolism, specifically the replenishment of fuel stores and intermediate metabolites.
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Affiliation(s)
- Mark R Viggars
- Research Institute for Sport & Exercise Science, Liverpool John Moores University, Liverpool, UK
- Department of Physiology and Aging, University of Florida, Gainesville, Florida, USA
- Myology Institute, University of Florida, Gainesville, Florida, USA
| | - Hazel Sutherland
- Research Institute for Sport & Exercise Science, Liverpool John Moores University, Liverpool, UK
| | - Christopher P Cardozo
- Spinal Cord Damage Research Center, James J. Peters VA Medical Center, Bronx, New York, USA
- Icahn School of Medicine, Mount Sinai, New York, New York, USA
| | - Jonathan C Jarvis
- Research Institute for Sport & Exercise Science, Liverpool John Moores University, Liverpool, UK
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11
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Koopmans PJ, Ismaeel A, Goljanek-Whysall K, Murach KA. The roles of miRNAs in adult skeletal muscle satellite cells. Free Radic Biol Med 2023; 209:228-238. [PMID: 37879420 PMCID: PMC10911817 DOI: 10.1016/j.freeradbiomed.2023.10.403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/16/2023] [Accepted: 10/22/2023] [Indexed: 10/27/2023]
Abstract
Satellite cells are bona fide muscle stem cells that are indispensable for successful post-natal muscle growth and regeneration after severe injury. These cells also participate in adult muscle adaptation in several capacities. MicroRNAs (miRNAs) are post-transcriptional regulators of mRNA that are implicated in several aspects of stem cell function. There is evidence to suggest that miRNAs affect satellite cell behavior in vivo during development and myogenic progenitor behavior in vitro, but the role of miRNAs in adult skeletal muscle satellite cells is less studied. In this review, we provide evidence for how miRNAs control satellite cell function with emphasis on satellite cells of adult skeletal muscle in vivo. We first outline how miRNAs are indispensable for satellite cell viability and control the phases of myogenesis. Next, we discuss the interplay between miRNAs and myogenic cell redox status, senescence, and communication to other muscle-resident cells during muscle adaptation. Results from recent satellite cell miRNA profiling studies are also summarized. In vitro experiments in primary myogenic cells and cell lines have been invaluable for exploring the influence of miRNAs, but we identify a need for novel genetic tools to further interrogate how miRNAs control satellite cell behavior in adult skeletal muscle in vivo.
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Affiliation(s)
- Pieter Jan Koopmans
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA; Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Ahmed Ismaeel
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, 40506, USA
| | - Katarzyna Goljanek-Whysall
- School of Medicine, College of Medicine, Nursing, and Health Sciences, University of Galway, Galway, Ireland
| | - Kevin A Murach
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, AR, 72701, USA; Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, 72701, USA.
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12
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Ismaeel A, Thomas NT, McCashland M, Vechetti IJ, Edman S, Lanner JT, Figueiredo VC, Fry CS, McCarthy JJ, Wen Y, Murach KA, von Walden F. Coordinated Regulation of Myonuclear DNA Methylation, mRNA, and miRNA Levels Associates With the Metabolic Response to Rapid Synergist Ablation-Induced Skeletal Muscle Hypertrophy in Female Mice. FUNCTION 2023; 5:zqad062. [PMID: 38020067 PMCID: PMC10666992 DOI: 10.1093/function/zqad062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 10/16/2023] [Accepted: 11/01/2023] [Indexed: 12/01/2023] Open
Abstract
The central dogma of molecular biology dictates the general flow of molecular information from DNA that leads to a functional cellular outcome. In skeletal muscle fibers, the extent to which global myonuclear transcriptional alterations, accounting for epigenetic and post-transcriptional influences, contribute to an adaptive stress response is not clearly defined. In this investigation, we leveraged an integrated analysis of the myonucleus-specific DNA methylome and transcriptome, as well as myonuclear small RNA profiling to molecularly define the early phase of skeletal muscle fiber hypertrophy. The analysis of myonucleus-specific mature microRNA and other small RNA species provides new directions for exploring muscle adaptation and complemented the methylation and transcriptional information. Our integrated multi-omics interrogation revealed a coordinated myonuclear molecular landscape during muscle loading that coincides with an acute and rapid reduction of oxidative metabolism. This response may favor a biosynthesis-oriented metabolic program that supports rapid hypertrophic growth.
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Affiliation(s)
- Ahmed Ismaeel
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40508, USA
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
| | - Nicholas T Thomas
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Athletic Training and Clinical Nutrition, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Mariah McCashland
- Department of Nutrition and Health Sciences, University of Nebraska–Lincoln, Lincoln, NE 68583, USA
| | - Ivan J Vechetti
- Department of Nutrition and Health Sciences, University of Nebraska–Lincoln, Lincoln, NE 68583, USA
| | - Sebastian Edman
- Department of Women’s and Children’s Health, Karolinska Institutet, Solna 17177, Sweden
| | - Johanna T Lanner
- Department of Physiology and Pharmacology, Karolinska Institutet, Solna 17177, Sweden
| | - Vandré C Figueiredo
- Department of Biological Sciences, Oakland University, Rochester, MI 48309, USA
| | - Christopher S Fry
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Athletic Training and Clinical Nutrition, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40508, USA
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
| | - Yuan Wen
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40508, USA
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Division of Biomedical Informatics, Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Kevin A Murach
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, AR 72701, USA
| | - Ferdinand von Walden
- Department of Women’s and Children’s Health, Karolinska Institutet, Solna 17177, Sweden
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13
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Ismaeel A, Valentino TR, Burke B, Goh J, Saliu TP, Albathi F, Owen A, McCarthy JJ, Wen Y. Acetate and succinate benefit host muscle energetics as exercise-associated post-biotics. Physiol Rep 2023; 11:e15848. [PMID: 37940330 PMCID: PMC10632089 DOI: 10.14814/phy2.15848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 10/19/2023] [Accepted: 10/19/2023] [Indexed: 11/10/2023] Open
Abstract
Recently, the gut microbiome has emerged as a potent modulator of exercise-induced systemic adaptation and appears to be crucial for mediating some of the benefits of exercise. This study builds upon previous evidence establishing a gut microbiome-skeletal muscle axis, identifying exercise-induced changes in microbiome composition. Metagenomics sequencing of fecal samples from non-exercise-trained controls or exercise-trained mice was conducted. Biodiversity indices indicated exercise training did not change alpha diversity. However, there were notable differences in beta-diversity between trained and untrained microbiomes. Exercise significantly increased the level of the bacterial species Muribaculaceae bacterium DSM 103720. Computation simulation of bacterial growth was used to predict metabolites that accumulate under in silico culture of exercise-responsive bacteria. We identified acetate and succinate as potential gut microbial metabolites that are produced by Muribaculaceae bacterium, which were then administered to mice during a period of mechanical overload-induced muscle hypertrophy. Although no differences were observed for the overall muscle growth response to succinate or acetate administration during the first 5 days of mechanical overload-induced hypertrophy, acetate and succinate increased skeletal muscle mitochondrial respiration. When given as post-biotics, succinate or acetate treatment may improve oxidative metabolism during muscle hypertrophy.
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Affiliation(s)
- Ahmed Ismaeel
- Department of Physiology, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
| | | | - Benjamin Burke
- Department of Physiology, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
| | - Jensen Goh
- Department of Physiology, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
| | - Tolulope P. Saliu
- Department of Physiology, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
| | - Fatmah Albathi
- Department of Pharmacology and Nutritional Sciences, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
| | - Allison Owen
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
- Department of Athletic TrainingCollege of Health SciencesUniversity of KentuckyLexingtonKentuckyUSA
| | - John J. McCarthy
- Department of Physiology, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
| | - Yuan Wen
- Department of Physiology, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKentuckyUSA
- Division of Biomedical Informatics, Department of Internal Medicine, College of MedicineUniversity of KentuckyLexingtonKentuckyUSA
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14
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Roberts MD, McCarthy JJ, Hornberger TA, Phillips SM, Mackey AL, Nader GA, Boppart MD, Kavazis AN, Reidy PT, Ogasawara R, Libardi CA, Ugrinowitsch C, Booth FW, Esser KA. Mechanisms of mechanical overload-induced skeletal muscle hypertrophy: current understanding and future directions. Physiol Rev 2023; 103:2679-2757. [PMID: 37382939 PMCID: PMC10625844 DOI: 10.1152/physrev.00039.2022] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 06/12/2023] [Accepted: 06/21/2023] [Indexed: 06/30/2023] Open
Abstract
Mechanisms underlying mechanical overload-induced skeletal muscle hypertrophy have been extensively researched since the landmark report by Morpurgo (1897) of "work-induced hypertrophy" in dogs that were treadmill trained. Much of the preclinical rodent and human resistance training research to date supports that involved mechanisms include enhanced mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling, an expansion in translational capacity through ribosome biogenesis, increased satellite cell abundance and myonuclear accretion, and postexercise elevations in muscle protein synthesis rates. However, several lines of past and emerging evidence suggest that additional mechanisms that feed into or are independent of these processes are also involved. This review first provides a historical account of how mechanistic research into skeletal muscle hypertrophy has progressed. A comprehensive list of mechanisms associated with skeletal muscle hypertrophy is then outlined, and areas of disagreement involving these mechanisms are presented. Finally, future research directions involving many of the discussed mechanisms are proposed.
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Affiliation(s)
- Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
| | - Troy A Hornberger
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Stuart M Phillips
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gustavo A Nader
- Department of Kinesiology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States
| | - Marni D Boppart
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States
| | - Andreas N Kavazis
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Paul T Reidy
- Department of Kinesiology, Nutrition and Health, Miami University, Oxford, Ohio, United States
| | - Riki Ogasawara
- Healthy Food Science Research Group, Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Cleiton A Libardi
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
| | - Carlos Ugrinowitsch
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri, United States
| | - Karyn A Esser
- Department of Physiology and Aging, College of Medicine, University of Florida, Gainesville, Florida, United States
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15
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Sun C, Swoboda CO, Petrany MJ, Parameswaran S, VonHandorf A, Weirauch MT, Lepper C, Millay DP. Lineage tracing of newly accrued nuclei in skeletal myofibers uncovers distinct transcripts and interplay between nuclear populations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.24.554609. [PMID: 37662191 PMCID: PMC10473681 DOI: 10.1101/2023.08.24.554609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Multinucleated skeletal muscle cells have an obligatory need to acquire additional nuclei through fusion with activated skeletal muscle stem cells when responding to both developmental and adaptive growth stimuli. A fundamental question in skeletal muscle biology has been the reason underlying this need for new nuclei in syncytial cells that already harbor hundreds of nuclei. To begin to answer this long-standing question, we utilized nuclear RNA-sequencing approaches and developed a lineage tracing strategy capable of defining the transcriptional state of recently fused nuclei and distinguishing this state from that of pre-existing nuclei. Our findings reveal the presence of conserved markers of newly fused nuclei both during development and after a hypertrophic stimulus in the adult. However, newly fused nuclei also exhibit divergent gene expression that is determined by the myogenic environment to which they fuse. Moreover, accrual of new nuclei through fusion is required for nuclei already resident in adult myofibers to mount a normal transcriptional response to a load-inducing stimulus. We propose a model of mutual regulation in the control of skeletal muscle development and adaptations, where newly fused and pre-existing myonuclear populations influence each other to maintain optimal functional growth.
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Affiliation(s)
- Chengyi Sun
- Division of Molecular Cardiovascular Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Casey O. Swoboda
- Division of Molecular Cardiovascular Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Michael J. Petrany
- Division of Molecular Cardiovascular Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Sreeja Parameswaran
- Division of Human Genetics, Center for Autoimmune Genetics and Etiology (CAGE), Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Andrew VonHandorf
- Division of Human Genetics, Center for Autoimmune Genetics and Etiology (CAGE), Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Matthew T. Weirauch
- Division of Biomedical Informatics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Division of Human Genetics, Center for Autoimmune Genetics and Etiology (CAGE), Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Christoph Lepper
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Douglas P. Millay
- Division of Molecular Cardiovascular Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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16
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Chaillou T, Montiel-Rojas D. Does the blunted stimulation of skeletal muscle protein synthesis by aging in response to mechanical load result from impaired ribosome biogenesis? FRONTIERS IN AGING 2023; 4:1171850. [PMID: 37256189 PMCID: PMC10225510 DOI: 10.3389/fragi.2023.1171850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 05/04/2023] [Indexed: 06/01/2023]
Abstract
Age-related loss of skeletal muscle mass leads to a reduction of strength. It is likely due to an inadequate stimulation of muscle protein synthesis (MPS) in response to anabolic stimuli, such as mechanical load. Ribosome biogenesis is a major determinant of translational capacity and is essential for the control of muscle mass. This mini-review aims to put forth the hypothesis that ribosome biogenesis is impaired by aging in response to mechanical load, which could contribute to the age-related anabolic resistance and progressive muscle atrophy. Recent animal studies indicate that aging impedes muscle hypertrophic response to mechanical overload. This is associated with an impaired transcription of ribosomal DNA (rDNA) by RNA polymerase I (Pol I), a limited increase in total RNA concentration, a blunted activation of AKT/mTOR pathway, and an increased phosphorylation of AMPK. In contrast, an age-mediated impairment of ribosome biogenesis is unlikely in response to electrical stimulations. In human, the hypertrophic response to resistance exercise training is diminished with age. This is accompanied by a deficit in long-term MPS and an absence of increased total RNA concentration. The results addressing the acute response to resistance exercise suggest an impaired Pol I-mediated rDNA transcription and attenuated activation/expression of several upstream regulators of ribosome biogenesis in muscles from aged individuals. Altogether, emerging evidence indicates that impaired ribosome biogenesis could partly explain age-related anabolic resistance to mechanical load, which may ultimately contribute to progressive muscle atrophy. Future research should develop more advanced molecular tools to provide in-depth analysis of muscle ribosome biogenesis.
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17
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Lim S, Lee DE, Morena da Silva F, Koopmans PJ, Vechetti IJ, von Walden F, Greene NP, Murach KA. MicroRNA control of the myogenic cell transcriptome and proteome: the role of miR-16. Am J Physiol Cell Physiol 2023; 324:C1101-C1109. [PMID: 36971422 PMCID: PMC10191132 DOI: 10.1152/ajpcell.00071.2023] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/20/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023]
Abstract
MicroRNAs (miRs) control stem cell biology and fate. Ubiquitously expressed and conserved miR-16 was the first miR implicated in tumorigenesis. miR-16 is low in muscle during developmental hypertrophy and regeneration. It is enriched in proliferating myogenic progenitor cells but is repressed during differentiation. The induction of miR-16 blocks myoblast differentiation and myotube formation, whereas knockdown enhances these processes. Despite a central role for miR-16 in myogenic cell biology, how it mediates its potent effects is incompletely defined. In this investigation, global transcriptomic and proteomic analyses after miR-16 knockdown in proliferating C2C12 myoblasts revealed how miR-16 influences myogenic cell fate. Eighteen hours after miR-16 inhibition, ribosomal protein gene expression levels were higher relative to control myoblasts and p53 pathway-related gene abundance was lower. At the protein level at this same time point, miR-16 knockdown globally upregulated tricarboxylic acid (TCA) cycle proteins while downregulating RNA metabolism-related proteins. miR-16 inhibition induced specific proteins associated with myogenic differentiation such as ACTA2, EEF1A2, and OPA1. We extend prior work in hypertrophic muscle tissue and show that miR-16 is lower in mechanically overloaded muscle in vivo. Our data collectively point to how miR-16 is implicated in aspects of myogenic cell differentiation. A deeper understanding of the role of miR-16 in myogenic cells has consequences for muscle developmental growth, exercise-induced hypertrophy, and regenerative repair after injury, all of which involve myogenic progenitors.
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Affiliation(s)
- Seongkyun Lim
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
| | - David E Lee
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
| | - Francielly Morena da Silva
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
| | - Pieter J Koopmans
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
- Cell and Molecular Biology Graduate Program, University of Arkansas, Fayetteville, Arkansas, United States
| | - Ivan J Vechetti
- Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, United States
| | - Ferdinand von Walden
- Neuropediatrics, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Nicholas P Greene
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
- Cell and Molecular Biology Graduate Program, University of Arkansas, Fayetteville, Arkansas, United States
| | - Kevin A Murach
- Department of Health, Human Performance, and Recreation, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, United States
- Cell and Molecular Biology Graduate Program, University of Arkansas, Fayetteville, Arkansas, United States
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18
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Study on the muscle transcriptome of two diverse Indian backyard poultry breeds acclimatized to different agro-ecological conditions. Mol Biol Rep 2023; 50:2453-2461. [PMID: 36598628 DOI: 10.1007/s11033-022-08223-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 12/19/2022] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Free-range (FR) poultry production systems are associated with quality products and improved welfare. All the 19 diverse chicken breeds of India have evolved under the FR system and are adapted to different agro-climatic conditions. It is vital to explore indigenous germplasm with modern genomic tools to have insights into genomic characteristics of production traits and adaptation. METHODS In this study, breast tissue transcriptome profiles were generated and analyzed from four biological replicates of two indigenous backyard poultry breeds of India-Ankaleshwar, a breed of the mainland, and Nicobari, a breed adapted to islands. The read quality of sequences was checked by FASTQC and processed reads were aligned to the reference genome (bGalGal1). RESULTS More than 94% mapping to the reference genome was observed for all samples. A total of 12,790 transcripts were common across both groups, while 657 were expressed only in Ankaleshwar and 169 in Nicobari. The highest expressed genes across both groups were associated mainly with muscle structure, contraction, and energy metabolism. The highly expressed genes identified in Ankaleshwar were involved in fatty acid catabolism and oxidative stress mitigation. Functional terms, pathways, and hub genes in Nicobari participated in muscle fiber growth, adipogenesis, and fatty acid anabolism. A key hub gene (RAC1) in Nicobari is a potential candidate affecting the laying rate in chickens. The qRT-PCR results also substantiate the RNA-seq results. CONCLUSION The findings provide a precious molecular resource to advance understanding of the genetic basis of adaptation, meat quality, and egg production in backyard chickens.
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19
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Bagley JR, Denes LT, McCarthy JJ, Wang ET, Murach KA. The myonuclear domain in adult skeletal muscle fibres: past, present and future. J Physiol 2023; 601:723-741. [PMID: 36629254 PMCID: PMC9931674 DOI: 10.1113/jp283658] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/06/2023] [Indexed: 01/12/2023] Open
Abstract
Most cells in the body are mononuclear whereas skeletal muscle fibres are uniquely multinuclear. The nuclei of muscle fibres (myonuclei) are usually situated peripherally which complicates the equitable distribution of gene products. Myonuclear abundance can also change under conditions such as hypertrophy and atrophy. Specialised zones in muscle fibres have different functions and thus distinct synthetic demands from myonuclei. The complex structure and regulatory requirements of multinuclear muscle cells understandably led to the hypothesis that myonuclei govern defined 'domains' to maintain homeostasis and facilitate adaptation. The purpose of this review is to provide historical context for the myonuclear domain and evaluate its veracity with respect to mRNA and protein distribution resulting from myonuclear transcription. We synthesise insights from past and current in vitro and in vivo genetically modified models for studying the myonuclear domain under dynamic conditions. We also cover the most contemporary knowledge on mRNA and protein transport in muscle cells. Insights from emerging technologies such as single myonuclear RNA-sequencing further inform our discussion of the myonuclear domain. We broadly conclude: (1) the myonuclear domain can be flexible during muscle fibre growth and atrophy, (2) the mechanisms and role of myonuclear loss and motility deserve further consideration, (3) mRNA in muscle is actively transported via microtubules and locally restricted, but proteins may travel far from a myonucleus of origin and (4) myonuclear transcriptional specialisation extends beyond the classic neuromuscular and myotendinous populations. A deeper understanding of the myonuclear domain in muscle may promote effective therapies for ageing and disease.
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Affiliation(s)
- James R. Bagley
- Muscle Physiology Laboratory, Department of Kinesiology, San Francisco State University, San Francisco, California
| | | | - John J. McCarthy
- The Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
- Department of Physiology, College of Medicine, University of Kentucky
| | - Eric T. Wang
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics, University of Florida, Gainesville, Florida
- Myology Institute, University of Florida
- Genetics Institute, University of Florida
| | - Kevin A. Murach
- Exercise Science Research Center, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas
- Cell and Molecular Biology Graduate Program, University of Arkansas
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20
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Jones RG, Dimet-Wiley A, Haghani A, da Silva FM, Brightwell CR, Lim S, Khadgi S, Wen Y, Dungan CM, Brooke RT, Greene NP, Peterson CA, McCarthy JJ, Horvath S, Watowich SJ, Fry CS, Murach KA. A molecular signature defining exercise adaptation with ageing and in vivo partial reprogramming in skeletal muscle. J Physiol 2023; 601:763-782. [PMID: 36533424 PMCID: PMC9987218 DOI: 10.1113/jp283836] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Exercise promotes functional improvements in aged tissues, but the extent to which it simulates partial molecular reprogramming is unknown. Using transcriptome profiling from (1) a skeletal muscle-specific in vivo Oct3/4, Klf4, Sox2 and Myc (OKSM) reprogramming-factor expression murine model; (2) an in vivo inducible muscle-specific Myc induction murine model; (3) a translatable high-volume hypertrophic exercise training approach in aged mice; and (4) human exercise muscle biopsies, we collectively defined exercise-induced genes that are common to partial reprogramming. Late-life exercise training lowered murine DNA methylation age according to several contemporary muscle-specific clocks. A comparison of the murine soleus transcriptome after late-life exercise training to the soleus transcriptome after OKSM induction revealed an overlapping signature that included higher JunB and Sun1. Also, within this signature, downregulation of specific mitochondrial and muscle-enriched genes was conserved in skeletal muscle of long-term exercise-trained humans; among these was muscle-specific Abra/Stars. Myc is the OKSM factor most induced by exercise in muscle and was elevated following exercise training in aged mice. A pulse of MYC rewired the global soleus muscle methylome, and the transcriptome after a MYC pulse partially recapitulated OKSM induction. A common signature also emerged in the murine MYC-controlled and exercise adaptation transcriptomes, including lower muscle-specific Melusin and reactive oxygen species-associated Romo1. With Myc, OKSM and exercise training in mice, as well habitual exercise in humans, the complex I accessory subunit Ndufb11 was lower; low Ndufb11 is linked to longevity in rodents. Collectively, exercise shares similarities with genetic in vivo partial reprogramming. KEY POINTS: Advances in the last decade related to cellular epigenetic reprogramming (e.g. DNA methylome remodelling) toward a pluripotent state via the Yamanaka transcription factors Oct3/4, Klf4, Sox2 and Myc (OKSM) provide a window into potential mechanisms for combatting the deleterious effects of cellular ageing. Using global gene expression analysis, we compared the effects of in vivo OKSM-mediated partial reprogramming in skeletal muscle fibres of mice to the effects of late-life murine exercise training in muscle. Myc is the Yamanaka factor most induced by exercise in skeletal muscle, and so we compared the MYC-controlled transcriptome in muscle to Yamanaka factor-mediated and exercise adaptation mRNA landscapes in mice and humans. A single pulse of MYC is sufficient to remodel the muscle methylome. We identify partial reprogramming-associated genes that are innately altered by exercise training and conserved in humans, and propose that MYC contributes to some of these responses.
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Affiliation(s)
- Ronald G. Jones
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | | | - Amin Haghani
- University of California Los Angeles, Department of Human Genetics, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
| | - Francielly Morena da Silva
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cachexia Research Laboratory, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Camille R. Brightwell
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Athletic Training and Clinical Nutrition, Lexington, KY, USA
| | - Seongkyun Lim
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cachexia Research Laboratory, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Sabin Khadgi
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
| | - Yuan Wen
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Physical Therapy, Lexington, KY, USA
| | - Cory M. Dungan
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Physical Therapy, Lexington, KY, USA
| | | | - Nicholas P. Greene
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cachexia Research Laboratory, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cell and Molecular Biology Graduate Program, Fayetteville, AR, USA
| | - Charlotte A. Peterson
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Physical Therapy, Lexington, KY, USA
- University of Kentucky, Department of Physiology, Lexington, KY, USA
| | - John J. McCarthy
- Altos Labs, San Diego, CA, USA
- University of Kentucky, Department of Physiology, Lexington, KY, USA
| | - Steve Horvath
- University of California Los Angeles, Department of Human Genetics, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
| | - Stanley J. Watowich
- Ridgeline Therapeutics, Houston, TX, USA
- University of Texas Medical Branch, Department of Biochemistry and Molecular Biology, Galveston, TX, USA
| | - Christopher S. Fry
- University of Kentucky Center for Muscle Biology, Lexington, KY, USA
- University of Kentucky, Department of Athletic Training and Clinical Nutrition, Lexington, KY, USA
| | - Kevin A. Murach
- University of Arkansas, Exercise Science Research Center, Department of Health, Human Performance, and Recreation, Fayetteville, AR, USA
- University of Arkansas, Cell and Molecular Biology Graduate Program, Fayetteville, AR, USA
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21
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Viggars MR, Sutherland H, Lanmüller H, Schmoll M, Bijak M, Jarvis JC. Adaptation of the transcriptional response to resistance exercise over 4 weeks of daily training. FASEB J 2023; 37:e22686. [PMID: 36468768 DOI: 10.1096/fj.202201418r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/05/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022]
Abstract
We present the time course of change in the muscle transcriptome 1 h after the last exercise bout of a daily resistance training program lasting 2, 10, 20, or 30 days. Daily exercise in rat tibialis anterior muscles (5 sets of 10 repetitions over 20 min) induced progressive muscle growth that approached a new stable state after 30 days. The acute transcriptional response changed along with progressive adaptation of the muscle phenotype. For example, expression of type 2B myosin was silenced. Time courses recently synthesized from human exercise studies do not demonstrate so clearly the interplay between the acute exercise response and the longer-term consequences of repeated exercise. We highlight classes of transcripts and transcription factors whose expression increases during the growth phase and declines again as the muscle adapts to a new daily pattern of activity and reduces its rate of growth. Myc appears to play a central role.
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Affiliation(s)
- Mark R Viggars
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK.,Department of Physiology and Aging, University of Florida, Gainesville, Florida, USA.,Myology Institute, University of Florida, Gainesville, Florida, USA
| | - Hazel Sutherland
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Hermann Lanmüller
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Martin Schmoll
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Manfred Bijak
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Jonathan C Jarvis
- Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool, UK
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22
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Vechetti IJ, Norrbom J, Alkner B, Hjalmarsson E, Palmcrantz A, Pontén E, Pingel J, von Walden F, Fernandez-Gonzalo R. Extracellular vesicle characteristics and microRNA content in cerebral palsy and typically developed individuals at rest and in response to aerobic exercise. Front Physiol 2022; 13:1072040. [PMID: 36620222 PMCID: PMC9811128 DOI: 10.3389/fphys.2022.1072040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
In this study, the properties of circulating extracellular vesicles (EVs) were examined in cerebral palsy (CP) and typically developed (TD) individuals at rest and after aerobic exercise, focusing on the size, concentration, and microRNA cargo of EVs. Nine adult individuals with CP performed a single exercise bout consisting of 45 min of Frame Running, and TD participants completed either 45 min of cycling (n = 10; TD EX) or were enrolled as controls with no exercise (n = 10; TD CON). Blood was drawn before and 30 min after exercise and analyzed for EV concentration, size, and microRNA content. The size of EVs was similar in CP vs. TD, and exercise had no effect. Individuals with CP had an overall lower concentration (∼25%, p < 0.05) of EVs. At baseline, let-7a, let-7b and let-7e were downregulated in individuals with CP compared to TD (p < 0.05), while miR-100 expression was higher, and miR-877 and miR-4433 lower in CP compared to TD after exercise (p < 0.05). Interestingly, miR-486 was upregulated ∼2-fold in the EVs of CP vs. TD both at baseline and after exercise. We then performed an in silico analysis of miR-486 targets and identified the satellite cell stemness factor Pax7 as a target of miR-486. C2C12 myoblasts were cultured with a miR-486 mimetic and RNA-sequencing was performed. Gene enrichment analysis revealed that several genes involved in sarcomerogenesis and extracellular matrix (ECM) were downregulated. Our data suggest that circulating miR-486 transported by EVs is elevated in individuals with CP and that miR-486 alters the transcriptome of myoblasts affecting both ECM- and sarcomerogenesis-related genes, providing a link to the skeletal muscle alterations observed in individuals with CP.
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Affiliation(s)
- Ivan J. Vechetti
- Department of Nutrition and Health Sciences, College of Education and Human Sciences, University of Nebraska-Lincoln, Lincoln, NE, United States
| | - Jessica Norrbom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Björn Alkner
- Department of Orthopaedics, Eksjö, Region Jönköping County and Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Emma Hjalmarsson
- Division of Pediatric Neurology, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Alexandra Palmcrantz
- Division of Pediatric Neurology, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Eva Pontén
- Division of Pediatric Neurology, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden,Department of Pediatric Orthopedic Surgery, Karolinska University Hospital, Stockholm, Sweden
| | - Jessica Pingel
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Ferdinand von Walden
- Division of Pediatric Neurology, Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Rodrigo Fernandez-Gonzalo
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden,Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden,*Correspondence: Rodrigo Fernandez-Gonzalo,
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