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Tangbjerg M, Damgaard A, Karlsen A, Svensson RB, Schjerling P, Gelabert‐Rebato M, Pankratova S, Sangild PT, Kjaer M, Mackey AL. Insulin-like growth factor-1 infusion in preterm piglets does not affect growth parameters of skeletal muscle or tendon tissue. Exp Physiol 2024; 109:1529-1544. [PMID: 38980930 PMCID: PMC11363143 DOI: 10.1113/ep092010] [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: 05/14/2024] [Accepted: 06/21/2024] [Indexed: 07/11/2024]
Abstract
Prematurity has physical consequences, such as lower birth weight, decreased muscle mass and increased risk of adult-onset metabolic disease. Insulin-like growth factor 1 (IGF-1) has therapeutic potential to improve the growth and quality of muscle and tendon in premature births, and thus attenuate some of these sequalae. We investigated the effect of IGF-1 on extensor carpi radialis muscle and biceps brachii tendon of preterm piglets. The preterm group consisted of 19-day-old preterm (10 days early) piglets, treated with either IGF-1 or vehicle. Term controls consisted of groups of 9-day-old piglets (D9) and 19-day-old piglets (D19). Muscle samples were analysed by immunofluorescence to determine the cross-sectional area (CSA) of muscle fibres, fibre type composition, satellite cell content and central nuclei-containing fibres in the muscle. Tendon samples were analysed for CSA, collagen content and maturation, and vascularization. Gene expression of the tendon was measured by RT-qPCR. Across all endpoints, we found no significant effect of IGF-1 treatment on preterm piglets. Preterm piglets had smaller muscle fibre CSA compared to D9 and D19 control group. Satellite cell content was similar across all groups. For tendon, we found an effect of age on tendon CSA, and mRNA levels of COL1A1, tenomodulin and scleraxis. Immunoreactivity for elastin and CD31, and several markers of tendon maturation, were increased in D9 compared to the preterm piglets. Collagen content was similar across groups. IGF-1 treatment of preterm-born piglets does not influence the growth and maturation of skeletal muscle and tendon.
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Affiliation(s)
- Malene Tangbjerg
- Institute of Sports Medicine CopenhagenDepartment of Orthopaedic SurgeryCopenhagen University Hospital – Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Ann Damgaard
- Institute of Sports Medicine CopenhagenDepartment of Orthopaedic SurgeryCopenhagen University Hospital – Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Anders Karlsen
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Rene B. Svensson
- Institute of Sports Medicine CopenhagenDepartment of Orthopaedic SurgeryCopenhagen University Hospital – Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Peter Schjerling
- Institute of Sports Medicine CopenhagenDepartment of Orthopaedic SurgeryCopenhagen University Hospital – Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Miriam Gelabert‐Rebato
- Research Institute of Biomedical and Health Sciences (IUIBS)University of Las Palmas de Gran Canaria, Las Palmas de Gran CanariaCanary IslandsSpain
| | - Stanislava Pankratova
- Comparative Pediatrics and Nutrition, Faculty of Health and Medical SciencesUniversity of CopenhagenFrederiksbergDenmark
| | - Per Torp Sangild
- Comparative Pediatrics and Nutrition, Faculty of Health and Medical SciencesUniversity of CopenhagenFrederiksbergDenmark
- Department of NeonatologyRigshospitaletCopenhagenDenmark
- Department of PediatricsOdense University HospitalOdenseDenmark
| | - Michael Kjaer
- Institute of Sports Medicine CopenhagenDepartment of Orthopaedic SurgeryCopenhagen University Hospital – Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Abigail L. Mackey
- Institute of Sports Medicine CopenhagenDepartment of Orthopaedic SurgeryCopenhagen University Hospital – Bispebjerg and FrederiksbergCopenhagenDenmark
- Center for Healthy AgingDepartment of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
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2
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Emmert ME, Emmert AS, Goh Q, Cornwall R. Sexual dimorphisms in skeletal muscle: current concepts and research horizons. J Appl Physiol (1985) 2024; 137:274-299. [PMID: 38779763 PMCID: PMC11343095 DOI: 10.1152/japplphysiol.00529.2023] [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: 07/31/2023] [Revised: 05/21/2024] [Accepted: 05/21/2024] [Indexed: 05/25/2024] Open
Abstract
The complex compositional and functional nature of skeletal muscle makes this organ an essential topic of study for biomedical researchers and clinicians. An additional layer of complexity is added with the consideration of sex as a biological variable. Recent research advances have revealed sexual dimorphisms in developmental biology, muscle homeostasis, adaptive responses, and disorders relating to skeletal muscle. Many of the observed sex differences have hormonal and molecular mechanistic underpinnings, whereas others have yet to be elucidated. Future research is needed to investigate the mechanisms dictating sex-based differences in the various aspects of skeletal muscle. As such, it is necessary that skeletal muscle biologists ensure that both female and male subjects are represented in biomedical and clinical studies to facilitate the successful testing and development of therapeutics for all patients.
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Affiliation(s)
- Marianne E Emmert
- Division of Orthopaedic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
| | - Andrew S Emmert
- Department of Orthopaedic Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
| | - Qingnian Goh
- Division of Orthopaedic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- Department of Orthopaedic Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
| | - Roger Cornwall
- Division of Orthopaedic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- Department of Orthopaedic Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
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3
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Montenegro CF, Skiles C, Kuszmaul DJ, Gouw A, Minchev K, Chambers TL, Raue U, Trappe TA, Trappe S. Fast and slow myofiber nuclei, satellite cells, and size distribution with lifelong endurance exercise in men and women. Physiol Rep 2024; 12:e16052. [PMID: 38987200 PMCID: PMC11236482 DOI: 10.14814/phy2.16052] [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: 03/01/2024] [Revised: 05/03/2024] [Accepted: 05/03/2024] [Indexed: 07/12/2024] Open
Abstract
We previously observed lifelong endurance exercise (LLE) influenced quadriceps whole-muscle and myofiber size in a fiber-type and sex-specific manner. The current follow-up exploratory investigation examined myofiber size regulators and myofiber size distribution in vastus lateralis biopsies from these same LLE men (n = 21, 74 ± 1 years) and women (n = 7, 72 ± 2 years) as well as old, healthy nonexercisers (OH; men: n = 10, 75 ± 1 years; women: n = 10, 75 ± 1 years) and young exercisers (YE; men: n = 10, 25 ± 1 years; women: n = 10, 25 ± 1 years). LLE exercised ~5 days/week, ~7 h/week for the previous 52 ± 1 years. Slow (myosin heavy chain (MHC) I) and fast (MHC IIa) myofiber nuclei/fiber, myonuclear domain, satellite cells/fiber, and satellite cell density were not influenced (p > 0.05) by LLE in men and women. The aging groups had ~50%-60% higher proportion of large (>7000 μm2) and small (<3000 μm2) myofibers (OH; men: 44%, women: 48%, LLE; men: 42%, women: 42%, YE; men: 27%, women: 29%). LLE men had triple the proportion of large slow fibers (LLE: 21%, YE: 7%, OH: 7%), while LLE women had more small slow fibers (LLE: 15%, YE: 8%, OH: 9%). LLE reduced by ~50% the proportion of small fast (MHC II containing) fibers in the aging men (OH: 14%, LLE: 7%) and women (OH: 35%, LLE: 18%). These data, coupled with previous findings, suggest that myonuclei and satellite cell content are uninfluenced by lifelong endurance exercise in men ~60-90 years, and this now also extends to septuagenarian lifelong endurance exercise women. Additionally, lifelong endurance exercise appears to influence the relative abundance of small and large myofibers (fast and slow) differently between men and women.
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Affiliation(s)
| | - Chad Skiles
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Dillon J Kuszmaul
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Aaron Gouw
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Kiril Minchev
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Toby L Chambers
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Ulrika Raue
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Todd A Trappe
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
| | - Scott Trappe
- Human Performance Laboratory, Ball State University, Muncie, Indiana, USA
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4
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Soendenbroe C, Karlsen A, Svensson RB, Kjaer M, Andersen JL, Mackey AL. Marked irregular myofiber shape is a hallmark of human skeletal muscle ageing and is reversed by heavy resistance training. J Cachexia Sarcopenia Muscle 2024; 15:306-318. [PMID: 38123165 PMCID: PMC10834339 DOI: 10.1002/jcsm.13405] [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: 06/08/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Age-related loss of strength is disproportionally greater than the loss of mass, suggesting maladaptations in the neuro-myo-tendinous system. Myofibers are often misshaped in aged and diseased muscle, but systematic analyses of large sample sets are lacking. Our aim was to investigate myofiber shape in relation to age, exercise, myofiber type, species and sex. METHODS Vastus lateralis muscle biopsies (n = 265) from 197 males and females, covering an age span of 20-97 years, were examined. The gastrocnemius and soleus muscles of 11 + 22-month-old male C57BL/6 mice were also examined. Immunofluorescence and ATPase stainings of muscle cross-sections were used to measure myofiber cross-sectional area (CSA) and perimeter. From these, a shape factor index (SFI) was calculated in a fibre-type-specific manner (type I/II in humans; type I/IIa/IIx/IIb in mice), with higher values indicating increased deformity. Heavy resistance training (RT) was performed three times per week for 3-4 months by a subgroup (n = 59). Correlation analyses were performed comparing SFI and CSA with age, muscle mass, maximal voluntary contraction (MVC), rate of force development and specific force (MVC/muscle mass). RESULTS In human muscle, SFI was positively correlated with age for both type I (R2 = 0.20) and II (R2 = 0.38) myofibers. When subjects were separated into age cohorts, SFI was lower for type I (4%, P < 0.001) and II (6%, P < 0.001) myofibers in young (20-36) compared with old (60-80) and higher for type I (5%, P < 0.05) and II (14%, P < 0.001) myofibers in the oldest old (>80) compared with old. The increased SFI in old muscle was observed in myofibers of all sizes. Within all three age cohorts, type II myofiber SFI was higher than that for type I myofiber (4-13%, P < 0.001), which was also the case in mice muscles (8-9%, P < 0.001). Across age cohorts, there was no difference between males and females in SFI for either type I (P = 0.496/0.734) or II (P = 0.176/0.585) myofibers. Multiple linear regression revealed that SFI, after adjusting for age and myofiber CSA, has independent explanatory power for 8/10 indices of muscle mass and function. RT reduced SFI of type II myofibers in both young and old (3-4%, P < 0.001). CONCLUSIONS Here, we identify type I and II myofiber shape in humans as a hallmark of muscle ageing that independently predicts volumetric and functional assessments of muscle health. RT reverts the shape of type II myofibers, suggesting that a lack of myofiber recruitment might lead to myofiber deformity.
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Affiliation(s)
- Casper Soendenbroe
- Department of Orthopedic SurgeryInstitute of Sports Medicine Copenhagen, Copenhagen University Hospital ‐ Bispebjerg and FrederiksbergCopenhagenDenmark
- Department of Clinical MedicineCenter for Healthy Aging, University of CopenhagenCopenhagenDenmark
| | - Anders Karlsen
- Department of Orthopedic SurgeryInstitute of Sports Medicine Copenhagen, Copenhagen University Hospital ‐ Bispebjerg and FrederiksbergCopenhagenDenmark
- Department of Clinical MedicineCenter for Healthy Aging, University of CopenhagenCopenhagenDenmark
- Department of Biomedical Sciences, Faculty of Health and Medical SciencesXlab, Center for Healthy Aging, University of CopenhagenCopenhagenDenmark
| | - Rene B. Svensson
- Department of Orthopedic SurgeryInstitute of Sports Medicine Copenhagen, Copenhagen University Hospital ‐ Bispebjerg and FrederiksbergCopenhagenDenmark
- Department of Clinical MedicineCenter for Healthy Aging, University of CopenhagenCopenhagenDenmark
| | - Michael Kjaer
- Department of Orthopedic SurgeryInstitute of Sports Medicine Copenhagen, Copenhagen University Hospital ‐ Bispebjerg and FrederiksbergCopenhagenDenmark
- Department of Clinical MedicineCenter for Healthy Aging, University of CopenhagenCopenhagenDenmark
| | - Jesper L. Andersen
- Department of Orthopedic SurgeryInstitute of Sports Medicine Copenhagen, Copenhagen University Hospital ‐ Bispebjerg and FrederiksbergCopenhagenDenmark
- Department of Clinical MedicineCenter for Healthy Aging, University of CopenhagenCopenhagenDenmark
| | - Abigail L. Mackey
- Department of Orthopedic SurgeryInstitute of Sports Medicine Copenhagen, Copenhagen University Hospital ‐ Bispebjerg and FrederiksbergCopenhagenDenmark
- Department of Clinical MedicineCenter for Healthy Aging, University of CopenhagenCopenhagenDenmark
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5
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Roberts MD, McCarthy JJ, Hornberger TA, Phillips SM, Mackey AL, Nader GA, Boppart MD, Kavazis AN, Reidy PT, Ogasawara R, Libardi CA, Ugrinowitsch C, Booth FW, Esser KA. Mechanisms of mechanical overload-induced skeletal muscle hypertrophy: current understanding and future directions. Physiol Rev 2023; 103:2679-2757. [PMID: 37382939 PMCID: PMC10625844 DOI: 10.1152/physrev.00039.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 06/12/2023] [Accepted: 06/21/2023] [Indexed: 06/30/2023] Open
Abstract
Mechanisms underlying mechanical overload-induced skeletal muscle hypertrophy have been extensively researched since the landmark report by Morpurgo (1897) of "work-induced hypertrophy" in dogs that were treadmill trained. Much of the preclinical rodent and human resistance training research to date supports that involved mechanisms include enhanced mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling, an expansion in translational capacity through ribosome biogenesis, increased satellite cell abundance and myonuclear accretion, and postexercise elevations in muscle protein synthesis rates. However, several lines of past and emerging evidence suggest that additional mechanisms that feed into or are independent of these processes are also involved. This review first provides a historical account of how mechanistic research into skeletal muscle hypertrophy has progressed. A comprehensive list of mechanisms associated with skeletal muscle hypertrophy is then outlined, and areas of disagreement involving these mechanisms are presented. Finally, future research directions involving many of the discussed mechanisms are proposed.
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Affiliation(s)
- Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
| | - Troy A Hornberger
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Stuart M Phillips
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gustavo A Nader
- Department of Kinesiology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States
| | - Marni D Boppart
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States
| | - Andreas N Kavazis
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Paul T Reidy
- Department of Kinesiology, Nutrition and Health, Miami University, Oxford, Ohio, United States
| | - Riki Ogasawara
- Healthy Food Science Research Group, Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Cleiton A Libardi
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
| | - Carlos Ugrinowitsch
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri, United States
| | - Karyn A Esser
- Department of Physiology and Aging, College of Medicine, University of Florida, Gainesville, Florida, United States
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6
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Skoglund E, Stål P, Lundberg TR, Gustafsson T, Tesch PA, Thornell LE. Skeletal muscle morphology, satellite cells, and oxidative profile in relation to physical function and lifelong endurance training in very old men. J Appl Physiol (1985) 2023; 134:264-275. [PMID: 36548511 DOI: 10.1152/japplphysiol.00343.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In the current study, we compared muscle morphology in three advanced aging cohorts that differed in physical function, including a unique cohort of lifelong endurance athletes. Biopsies from the vastus lateralis muscle of seven lifelong endurance athletes (EAs) aged 82-92 yr, and 19 subjects from the Uppsala Longitudinal Study of Adult Men (ULSAM) aged 87-91 yr were analyzed. ULSAM subjects were divided into high- (n = 9, HF) and low- (n = 10, LF) function groups based on strength and physical function tests. The analysis included general morphology, fiber type and cross-sectional area, capillarization, deficient cytochrome c oxidase (COX) activity, number of myonuclei and satellite cells, and markers of regeneration and denervation. Fibers with central nuclei and/or nuclear clumps were observed in all groups. EA differed from LF and HF by having a higher proportion of type I fibers, 52% more capillaries in relation to fiber area, fewer COX-negative fibers, and less variation in fiber sizes (all P < 0.05). There were no differences between the groups in the number of myonuclei and satellite cells per fiber, and no significant differences between LF and HF (P > 0.05). In conclusion, signs of aging were evident in the muscle morphology of all groups, but neither endurance training status nor physical function influenced signs of regeneration and denervation processes. Lifelong endurance training, but not higher physical function, was associated with higher muscle oxidative capacity, even beyond the age of 80.NEW & NOTEWORTHY Here we show that lifelong endurance training, but not physical function, is associated with higher muscle oxidative capacity, even beyond the age of 80 yr. Neither endurance training status nor physical function was significantly associated with satellite cells or markers of regeneration and denervation in muscle biopsies from these very old men.
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Affiliation(s)
- Elisabeth Skoglund
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Per Stål
- Department of Integrative Medical Biology, Umeå University, Umeå, Sweden
| | - Tommy R Lundberg
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Thomas Gustafsson
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Per A Tesch
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Lars-Eric Thornell
- Department of Integrative Medical Biology, Umeå University, Umeå, Sweden
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7
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Viggars MR, Owens DJ, Stewart C, Coirault C, Mackey AL, Jarvis JC. PCM1 labeling reveals myonuclear and nuclear dynamics in skeletal muscle across species. Am J Physiol Cell Physiol 2023; 324:C85-C97. [PMID: 36409178 DOI: 10.1152/ajpcell.00285.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Myonuclei transcriptionally regulate muscle fibers during homeostasis and adaptation to exercise. Their subcellular location and quantity are important when characterizing phenotypes of myopathies, the effect of treatments, and understanding the roles of satellite cells in muscle adaptation and muscle "memory." Difficulties arise in identifying myonuclei due to their proximity to the sarcolemma and closely residing interstitial cell neighbors. We aimed to determine to what extent (pericentriolar material-1) PCM1 is a specific marker of myonuclei in vitro and in vivo. Single isolated myofibers and cross sections from mice and humans were studied from several models including wild-type and Lamin A/C mutant mice after functional overload and damage and recovery in humans following forced eccentric contractions. Fibers were immunolabeled for PCM1, Pax7, and DNA. C2C12 myoblasts were also studied to investigate changes in PCM1 localization during myogenesis. PCM1 was detected at not only the nuclear envelope of myonuclei in mature myofibers and in newly formed myotubes but also centrosomes in proliferating myogenic precursors, which may or may not fuse to join the myofiber syncytium. PCM1 was also detected in nonmyogenic nuclei near the sarcolemma, especially in regenerating areas of the Lmna+/ΔK32 mouse and damaged human muscle. Although PCM1 is not completely specific to myonuclei, the impact that PCM1+ macrophages and interstitial cells have on myonuclei counts would be small in healthy muscle. PCM1 may prove useful as a marker of satellite cell dynamics due to the distinct change in localization during differentiation, revealing satellite cells in their quiescent (PCM1-), proliferating (PCM1+ centrosome), and prefusion states (PCM1+ nuclear envelope).
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Affiliation(s)
- Mark R Viggars
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom.,Department of Physiology and Aging, University of Florida, Gainesville, Florida.,Myology Institute, University of Florida, Gainesville, Florida
| | - Daniel J Owens
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom.,Sorbonne Université, INSERM, Myology Research Center, Paris, France
| | - Claire Stewart
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | | | - Abigail L Mackey
- Department of Orthopaedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, Center for Healthy Aging, Xlab, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Jonathan C Jarvis
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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8
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Binet ER, McKenna CF, Salvador AF, Martinez IG, Alamilla RA, Collao N, Bodnariuc G, Khan NA, Paluska SA, Burd NA, De Lisio M. Sex-based comparisons of muscle cellular adaptations after 10 weeks of progressive resistance training in middle-aged adults. J Appl Physiol (1985) 2023; 134:116-129. [PMID: 36454678 DOI: 10.1152/japplphysiol.00274.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Resistance training combined with adequate protein intake supports skeletal muscle strength and hypertrophy. These adaptations are supported by the action of muscle stem cells (MuSCs), which are regulated, in part, by fibro-adipogenic progenitors (FAPs) and circulating factors delivered through capillaries. It is unclear if middle-aged males and females have similar adaptations to resistance training at the cellular level. To address this gap, 27 (13 males, 14 females) middle-aged (40-64 yr) adults participated in 10 wk of whole body resistance training with dietary counseling. Muscle biopsies were collected from the vastus lateralis pre- and posttraining. Type II fiber cross-sectional area increased similarly with training in both sexes (P = 0.014). MuSC content was not altered with training; however, training increased PDGFRα+/CD90+ FAP content (P < 0.0001) and reduced PDGFRα+/CD90- FAP content (P = 0.044), independent of sex. The number of CD31+ capillaries per fiber also increased similarly in both sexes (P < 0.05). These results suggest that muscle fiber hypertrophy, stem/progenitor cell, and capillary adaptations are similar between middle-aged males and females in response to whole body resistance training.NEW & NOTEWORTHY We demonstrate that resistance training-induced increases in fiber hypertrophy, FAP content, and capillarization are similar between middle-aged males and females.
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Affiliation(s)
- Emileigh R Binet
- School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Colleen F McKenna
- Division of Nutritional Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Amadeo F Salvador
- Department of Kinesiology and Community Health, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Isabel G Martinez
- Department of Kinesiology and Community Health, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Rafael A Alamilla
- Department of Kinesiology and Community Health, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Nicolas Collao
- School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Giana Bodnariuc
- School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada
| | - Naiman A Khan
- Division of Nutritional Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois.,Department of Kinesiology and Community Health, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Scott A Paluska
- Department of Family Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Nicholas A Burd
- Division of Nutritional Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois.,Department of Kinesiology and Community Health, University of Illinois Urbana-Champaign, Urbana, Illinois
| | - Michael De Lisio
- School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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9
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Rahmati M, McCarthy JJ, Malakoutinia F. Myonuclear permanence in skeletal muscle memory: a systematic review and meta-analysis of human and animal studies. J Cachexia Sarcopenia Muscle 2022; 13:2276-2297. [PMID: 35961635 PMCID: PMC9530508 DOI: 10.1002/jcsm.13043] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/24/2022] [Accepted: 06/13/2022] [Indexed: 12/09/2022] Open
Abstract
One aspect of skeletal muscle memory is the ability of a previously trained muscle to hypertrophy more rapidly following a period of detraining. Although the molecular basis of muscle memory remains to be fully elucidated, one potential mechanism thought to mediate muscle memory is the permanent retention of myonuclei acquired during the initial phase of hypertrophic growth. However, myonuclear permanence is debated and would benefit from a meta-analysis to clarify the current state of the field for this important aspect of skeletal muscle plasticity. The objective of this study was to perform a meta-analysis to assess the permanence of myonuclei associated with changes in physical activity and ageing. When available, the abundance of satellite cells (SCs) was also considered given their potential influence on changes in myonuclear abundance. One hundred forty-seven peer-reviewed articles were identified for inclusion across five separate meta-analyses; (1-2) human and rodent studies assessed muscle response to hypertrophy; (3-4) human and rodent studies assessed muscle response to atrophy; and (5) human studies assessed muscle response with ageing. Skeletal muscle hypertrophy was associated with higher myonuclear content that was retained in rodents, but not humans, with atrophy (SMD = -0.60, 95% CI -1.71 to 0.51, P = 0.29, and MD = 83.46, 95% CI -649.41 to 816.32, P = 0.82; respectively). Myonuclear and SC content were both lower following atrophy in humans (MD = -11, 95% CI -0.19 to -0.03, P = 0.005, and SMD = -0.49, 95% CI -0.77 to -0.22, P = 0.0005; respectively), although the response in rodents was affected by the type of muscle under consideration and the mode of atrophy. Whereas rodent myonuclei were found to be more permanent regardless of the mode of atrophy, atrophy of ≥30% was associated with a reduction in myonuclear content (SMD = -1.02, 95% CI -1.53 to -0.51, P = 0.0001). In humans, sarcopenia was accompanied by a lower myonuclear and SC content (MD = 0.47, 95% CI 0.09 to 0.85, P = 0.02, and SMD = 0.78, 95% CI 0.37-1.19, P = 0.0002; respectively). The major finding from the present meta-analysis is that myonuclei are not permanent but are lost during periods of atrophy and with ageing. These findings do not support the concept of skeletal muscle memory based on the permanence of myonuclei and suggest other mechanisms, such as epigenetics, may have a more important role in mediating this aspect of skeletal muscle plasticity.
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Affiliation(s)
- Masoud Rahmati
- Department of Physical Education and Sport Sciences, Faculty of Literature and Human SciencesLorestan UniversityKhorramabadIran
| | - John J. McCarthy
- Department of PhysiologyUniversity of KentuckyLexingtonKYUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKYUSA
| | - Fatemeh Malakoutinia
- Department of Physical Education and Sport Sciences, Faculty of Literature and Human SciencesLorestan UniversityKhorramabadIran
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10
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Brook MS, Wilkinson DJ, Tarum J, Mitchell KW, Lund JL, Phillips BE, Szewczyk NJ, Kadi F, Greenhaff PL, Smith K, Atherton PJ. Neither myonuclear accretion nor a myonuclear domain size ceiling is a feature of the attenuated hypertrophic potential of aged human skeletal muscle. GeroScience 2022; 45:451-462. [PMID: 36083436 PMCID: PMC9886697 DOI: 10.1007/s11357-022-00651-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 08/25/2022] [Indexed: 02/03/2023] Open
Abstract
Ageing limits growth capacity of skeletal muscle (e.g. in response to resistance exercise), but the role of satellite cell (SC) function in driving this phenomenon is poorly defined. Younger (Y) (~ 23 years) and older (O) men (~ 69 years) (normal-weight BMI) underwent 6 weeks of unilateral resistance exercise training (RET). Muscle biopsies were taken at baseline and after 3-/6-week training. We determined muscle size by fibre CSA (and type), SC number, myonuclei counts and DNA synthesis (via D2O ingestion). At baseline, there were no significant differences in fibre areas between Y and O. RET increased type I fibre area in Y from baseline at both 3 weeks and 6 weeks (baseline: 4509 ± 534 µm2, 3 weeks; 5497 ± 510 µm2 P < 0.05, 6 weeks; 5402 ± 352 µm2 P < 0.05), whilst O increased from baseline at 6 weeks only (baseline 5120 ± 403 µm2, 3 weeks; 5606 ± 620 µm2, 6 weeks; 6017 ± 482 µm2 P < 0.05). However, type II fibre area increased from baseline in Y at both 3 weeks and 6 weeks (baseline: 4949 ± 459 µm2, 3 weeks; 6145 ± 484 µm2 (P < 0.01), 6 weeks; 5992 ± 491 µm2 (P < 0.01), whilst O showed no change (baseline 5210 ± 410 µm2, 3 weeks; 5356 ± 535 µm2 (P = 0.9), 6 weeks; 5857 ± 478 µm2 (P = 0.1). At baseline, there were no differences in fibre myonuclei number between Y and O. RET increased type I fibre myonuclei number from baseline in both Y and O at 3 weeks and 6 weeks with RET (younger: baseline 2.47 ± 0.16, 3 weeks; 3.19 ± 0.16 (P < 0.001), 6 weeks; 3.70 ± 0.29 (P < 0.0001); older: baseline 2.29 ± 0.09, 3 weeks; 3.01 ± 0.09 (P < 0.001), 6 weeks; 3.65 ± 0.18 (P < 0.0001)). Similarly, type II fibre myonuclei number increased from baseline in both Y and O at 3 weeks and 6 weeks (younger: baseline 2.49 ± 0.14, 3 weeks; 3.31 ± 0.21 (P < 0.001), 6 weeks; 3.86 ± 0.29 (P < 0.0001); older: baseline 2.43 ± 0.12, 3 weeks; 3.37 ± 0.12 (P < 0.001), 6 weeks; 3.81 ± 0.15 (P < 0.0001)). DNA synthesis rates %.d-1 exhibited a main effect of training but no age discrimination. Declines in myonuclei addition do not underlie impaired muscle growth capacity in older humans, supporting ribosomal and proteostasis impairments as we have previously reported.
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Affiliation(s)
- Matthew S. Brook
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK ,School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Daniel J. Wilkinson
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Janelle Tarum
- School of Health Sciences, Örebro University, Örebro, Sweden
| | - Kyle W. Mitchell
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Jonathan L. Lund
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Bethan E. Phillips
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Nathaniel J. Szewczyk
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Fawzi Kadi
- School of Health Sciences, Örebro University, Örebro, Sweden
| | - Paul L. Greenhaff
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK ,School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Ken Smith
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
| | - Philip J. Atherton
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham BRC, Centre of Metabolism, Ageing and Physiology (COMAP), School of Medicine, University of Nottingham, Derby, UK
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11
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Moesgaard L, Jessen S, Mackey AL, Hostrup M. Myonuclear addition is associated with sex-specific fiber hypertrophy and occurs in relation to fiber perimeter not cross-sectional area. J Appl Physiol (1985) 2022; 133:732-741. [PMID: 35952346 DOI: 10.1152/japplphysiol.00235.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It is unclear whether resistance training-induced myofiber hypertrophy is affected by sex, and whether myonuclear addition occurs in relation to the myonuclear domain and can contribute to explaining a potential sex-specific hypertrophic response. This study investigated the effect of 8 weeks of resistance training on myofiber hypertrophy and myonuclear addition in 12 males (28±7 years; mean±SD) and 12 females (27±7 years). Muscle biopsies were collected from m. vastus lateralis before and after the training intervention and analyzed by immunohistochemistry for fiber type and size, satellite cells, and myonuclei. Hypertrophy of type I fibers was greater in males than females (P<0.05), whereas hypertrophy of type II fibers was similar between sexes (P=0.158‒0.419). Expansion of the satellite cell pool (P=0.132‒0.667) and myonuclear addition (P=0.064‒0.228) did not differ significantly between sexes, irrespective of myofiber type. However, when individual responses to resistance training were assessed, myonuclear addition was strongly correlated with fiber hypertrophy (r=0.68‒0.85, P<0.001). While myofiber hypertrophy was accompanied by an increase in myonuclear domain (P<0.05), fiber perimeter per myonucleus remained constant throughout the study (P=0.096‒0.666). These findings indicate that myonuclear addition occurs in relation to the fiber perimeter per myonucleus, not the myonuclear domain, and has a substantial role in muscle hypertrophy, but does not fully explain greater hypertrophy of type I fibers in males than females.
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Affiliation(s)
- Lukas Moesgaard
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Søren Jessen
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - 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.,Xlab, Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Morten Hostrup
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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12
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Soendenbroe C, Flindt Heisterberg MF, Schjerling P, Kjaer M, Andersen JL, Mackey AL. Human skeletal muscle acetylcholine receptor gene expression in elderly males performing heavy resistance exercise. Am J Physiol Cell Physiol 2022; 323:C159-C169. [PMID: 35649253 DOI: 10.1152/ajpcell.00365.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Muscle fiber denervation is a major contributor to the decline in muscle mass and function during aging. Heavy resistance exercise is an effective tool for increasing muscle mass and strength, but whether it can rescue denervated muscle fibers remains unclear. Therefore, the purpose of this study was to investigate the potential of heavy resistance exercise to modify indices of denervation in healthy elderly individuals. 38 healthy elderly men (72±5 years) underwent 16 weeks of heavy resistance exercise while 20 healthy elderly men (72±6 years) served as non-exercising sedentary controls. Muscle biopsies were obtained pre and post training, and midway at eight weeks. Biopsies were analysed by immunofluorescence for the prevalence of myofibers expressing embryonic myosin (MyHCe), neonatal myosin (MyHCn), nestin, and neural cell adhesion molecule (NCAM), and by RT-qPCR for gene expression levels of acetylcholine receptor (AChR) subunits, MyHCn, MyHCe, p16 and Ki67. In addition to increases in strength and type II fiber hypertrophy, heavy resistance exercise training led to a decrease in AChR α1 and ε subunit mRNA (at eight weeks). Changes in gene expression levels of the α1 and ε AChR subunits with eight weeks of heavy resistance exercise supports the role of this type of exercise in targeting stability of the neuromuscular junction. The number of fibers positive for NCAM, nestin, and MyHCn was not affected, suggesting that a longer timeframe is needed for adaptations to manifest at the protein level.
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Affiliation(s)
- Casper Soendenbroe
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen NV, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Mette F Flindt Heisterberg
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen NV, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen NV, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen NV, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Jesper L Andersen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen NV, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen NV, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
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13
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O'Bryan SJ, Hiam D. The benefits of physical activity on neuromuscular structure and function in old age. J Physiol 2022; 600:2283-2285. [PMID: 35393657 DOI: 10.1113/jp283102] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Steven J O'Bryan
- Institute for Health and Sport (IHeS), Victoria University, Melbourne, Australia
| | - Danielle Hiam
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia
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14
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Soendenbroe C, Dahl CL, Meulengracht C, Tamáš M, Svensson RB, Schjerling P, Kjaer M, Andersen JL, Mackey AL. Preserved stem cell content and innervation profile of elderly human skeletal muscle with lifelong recreational exercise. J Physiol 2022; 600:1969-1989. [PMID: 35229299 PMCID: PMC9315046 DOI: 10.1113/jp282677] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/14/2022] [Indexed: 11/21/2022] Open
Abstract
Abstract Muscle fibre denervation and declining numbers of muscle stem (satellite) cells are defining characteristics of ageing skeletal muscle. The aim of this study was to investigate the potential for lifelong recreational exercise to offset muscle fibre denervation and compromised satellite cell content and function, both at rest and under challenged conditions. Sixteen elderly lifelong recreational exercisers (LLEX) were studied alongside groups of age‐matched sedentary (SED) and young subjects. Lean body mass and maximal voluntary contraction were assessed, and a strength training bout was performed. From muscle biopsies, tissue and primary myogenic cell cultures were analysed by immunofluorescence and RT‐qPCR to assess myofibre denervation and satellite cell quantity and function. LLEX demonstrated superior muscle function under challenged conditions. When compared with SED, the muscle of LLEX was found to contain a greater content of satellite cells associated with type II myofibres specifically, along with higher mRNA levels of the beta and gamma acetylcholine receptors (AChR). No difference was observed between LLEX and SED for the proportion of denervated fibres or satellite cell function, as assessed in vitro by myogenic cell differentiation and fusion index assays. When compared with inactive counterparts, the skeletal muscle of lifelong exercisers is characterised by greater fatigue resistance under challenged conditions in vivo, together with a more youthful tissue satellite cell and AChR profile. Our data suggest a little recreational level exercise goes a long way in protecting against the emergence of classic phenotypic traits associated with the aged muscle. Key points The detrimental effects of ageing can be partially offset by lifelong self‐organized recreational exercise, as evidence by preserved type II myofibre‐associated satellite cells, a beneficial muscle innervation status and greater fatigue resistance under challenged conditions. Satellite cell function (in vitro), muscle fibre size and muscle fibre denervation determined by immunofluorescence were not affected by recreational exercise. Individuals that are recreationally active are far more abundant than master athletes, which sharply increases the translational perspective of the present study. Future studies should further investigate recreational activity in relation to muscle health, while also including female participants.
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Affiliation(s)
- Casper Soendenbroe
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark
| | - Christopher L Dahl
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark
| | - Christopher Meulengracht
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark
| | - Michal Tamáš
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark
| | - Rene B Svensson
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark
| | - Jesper L Andersen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Building 8, Nielsine Nielsens vej 11, Copenhagen, NV, 2400, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, Copenhagen N, 2200, Denmark
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15
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Prokopidis K, Giannos P, Witard OC, Peckham D, Ispoglou T. Aberrant mitochondrial homeostasis at the crossroad of musculoskeletal ageing and non-small cell lung cancer. PLoS One 2022; 17:e0273766. [PMID: 36067173 PMCID: PMC9447904 DOI: 10.1371/journal.pone.0273766] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 08/12/2022] [Indexed: 11/19/2022] Open
Abstract
Cancer cachexia is accompanied by muscle atrophy, sharing multiple common catabolic pathways with sarcopenia, including mitochondrial dysfunction. This study investigated gene expression from skeletal muscle tissues of older healthy adults, who are at risk of age-related sarcopenia, to identify potential gene biomarkers whose dysregulated expression and protein interference were involved in non-small cell lung cancer (NSCLC). Screening of the literature resulted in 14 microarray datasets (GSE25941, GSE28392, GSE28422, GSE47881, GSE47969, GSE59880 in musculoskeletal ageing; GSE118370, GSE33532, GSE19804, GSE18842, GSE27262, GSE19188, GSE31210, GSE40791 in NSCLC). Differentially expressed genes (DEGs) were used to construct protein-protein interaction networks and retrieve clustering gene modules. Overlapping module DEGs were ranked based on 11 topological algorithms and were correlated with prognosis, tissue expression, and tumour purity in NSCLC. The analysis revealed that the dysregulated expression of the mammalian mitochondrial ribosomal proteins, Mitochondrial Ribosomal Protein S26 (MRPS26), Mitochondrial Ribosomal Protein S17 (MRPS17), Mitochondrial Ribosomal Protein L18 (MRPL18) and Mitochondrial Ribosomal Protein L51 (MRPL51) were linked to reduced survival and tumour purity in NSCLC while tissue expression of the same genes followed an opposite direction in healthy older adults. These results support a potential link between the mitochondrial ribosomal microenvironment in ageing muscle and NSCLC. Further studies comparing changes in sarcopenia and NSCLC associated cachexia are warranted.
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Affiliation(s)
- Konstantinos Prokopidis
- Society of Meta-Research and Biomedical Innovation, London, United Kingdom
- Department of Musculoskeletal Biology, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Panagiotis Giannos
- Society of Meta-Research and Biomedical Innovation, London, United Kingdom
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, United Kingdom
- * E-mail:
| | - Oliver C. Witard
- Faculty of Life Sciences and Medicine, Centre for Human and Applied Physiological Sciences, King’s College London, London, United Kingdom
| | - Daniel Peckham
- Leeds Institute of Medical Research at St James’s, University of Leeds, Leeds, United Kingdom
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16
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Gustafsson T, Ulfhake B. Sarcopenia: What Is the Origin of This Aging-Induced Disorder? Front Genet 2021; 12:688526. [PMID: 34276788 PMCID: PMC8285098 DOI: 10.3389/fgene.2021.688526] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/10/2021] [Indexed: 01/03/2023] Open
Abstract
We here review the loss of muscle function and mass (sarcopenia) in the framework of human healthspan and lifespan, and mechanisms involved in aging. The rapidly changing composition of the human population will impact the incidence and the prevalence of aging-induced disorders such as sarcopenia and, henceforth, efforts to narrow the gap between healthspan and lifespan should have top priority. There are substantial knowledge gaps in our understanding of aging. Heritability is estimated to account for only 25% of lifespan length. However, as we push the expected lifespan at birth toward those that we consider long-lived, the genetics of aging may become increasingly important. Linkage studies of genetic polymorphisms to both the susceptibility and aggressiveness of sarcopenia are still missing. Such information is needed to shed light on the large variability in clinical outcomes between individuals and why some respond to interventions while others do not. We here make a case for the concept that sarcopenia has a neurogenic origin and that in manifest sarcopenia, nerve and myofibers enter into a vicious cycle that will escalate the disease progression. We point to gaps in knowledge, for example the crosstalk between the motor axon, terminal Schwann cell, and myofiber in the denervation processes that leads to a loss of motor units and muscle weakness. Further, we argue that the operational definition of sarcopenia should be complemented with dynamic metrics that, along with validated biomarkers, may facilitate early preclinical diagnosis of individuals vulnerable to develop advanced sarcopenia. We argue that preventive measures are likely to be more effective to counter act aging-induced disorders than efforts to treat manifest clinical conditions. To achieve compliance with a prescription of preventive measures that may be life-long, we need to identify reliable predictors to design rational and convincing interventions.
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Affiliation(s)
- Thomas Gustafsson
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Brun Ulfhake
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
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17
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Soendenbroe C, Andersen JL, Mackey AL. Muscle-nerve communication and the molecular assessment of human skeletal muscle denervation with aging. Am J Physiol Cell Physiol 2021; 321:C317-C329. [PMID: 34161153 DOI: 10.1152/ajpcell.00174.2021] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Muscle fiber denervation is a major contributor to the decline in physical function observed with aging. Denervation can occur through breakdown of the neuromuscular junctions (NMJ) itself, affecting only that particular fiber, or through the death of a motor neuron, which can lead to a loss of all the muscle fibers in that motor unit. In this review, we discuss the muscle-nerve relationship, where signaling from both the motor neuron and the muscle fiber is required for maximal preservation of neuromuscular function in old age. Physical activity is likely to be the most important single factor that can contribute to this preservation. Furthermore, we propose that inactivity is not an innocent bystander, but plays an active role in denervation through the production of signals hostile to neuron survival. Investigating denervation in human muscle tissue samples is challenging due to the shared protein profile of regenerating and denervated muscle fibers. In this review, we provide a detailed overview of the key traits observed in immunohistochemical preparations of muscle biopsies from healthy, young, and elderly individuals. Overall, a combination of assessing tissue samples, circulating biomarkers, and electrophysiological assessments in humans will prove fruitful in the quest to gain more understanding of denervation of skeletal muscle. In addition, cell culture models represent a valuable tool in the search for key signaling factors exchanged between muscle and nerve, and which exercise has the capacity to alter.
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Affiliation(s)
- Casper Soendenbroe
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Jesper L Andersen
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Abigail L Mackey
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
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18
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Mølmen KS, Hammarström D, Pedersen K, Lian Lie AC, Steile RB, Nygaard H, Khan Y, Hamarsland H, Koll L, Hanestadhaugen M, Eriksen AL, Grindaker E, Whist JE, Buck D, Ahmad R, Strand TA, Rønnestad BR, Ellefsen S. Vitamin D 3 supplementation does not enhance the effects of resistance training in older adults. J Cachexia Sarcopenia Muscle 2021; 12:599-628. [PMID: 33788419 PMCID: PMC8200443 DOI: 10.1002/jcsm.12688] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 12/30/2020] [Accepted: 01/26/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Lifestyle therapy with resistance training is a potent measure to counteract age-related loss in muscle strength and mass. Unfortunately, many individuals fail to respond in the expected manner. This phenomenon is particularly common among older adults and those with chronic diseases (e.g. chronic obstructive pulmonary disease, COPD) and may involve endocrine variables such as vitamin D. At present, the effects of vitamin D supplementation on responses to resistance training remain largely unexplored. METHODS Ninety-five male and female participants (healthy, n = 71; COPD, n = 24; age 68 ± 5 years) were randomly assigned to receive either vitamin D3 or placebo supplementation for 28 weeks in a double-blinded manner (latitude 61°N, September-May). Seventy-eight participants completed the RCT, which was initiated by 12 weeks of supplementation-only (two weeks with 10 000 IU/day, followed by 2000 IU/day), followed by 13 weeks of combined supplementation (2000 IU/day) and supervised whole-body resistance training (twice weekly), interspersed with testing and measurements. Outcome measures included multiple assessments of muscle strength (nvariables = 7), endurance performance (n = 6), and muscle mass (n = 3, legs, primary), as well as muscle quality (legs), muscle biology (m. vastus lateralis; muscle fibre characteristics, transcriptome), and health-related variables (e.g. visceral fat mass and blood lipid profile). For main outcome domains such as muscle strength and muscle mass, weighted combined factors were calculated from the range of singular assessments. RESULTS Overall, 13 weeks of resistance training increased muscle strength (13% ± 8%), muscle mass (9% ± 8%), and endurance performance (one-legged, 23% ± 15%; whole-body, 8% ± 7%), assessed as weighted combined factors, and were associated with changes in health variables (e.g. visceral fat, -6% ± 21%; [LDL]serum , -4% ± 14%) and muscle tissue characteristics such as fibre type proportions (e.g. IIX, -3% points), myonuclei per fibre (30% ± 65%), total RNA/rRNA abundances (15%/6-19%), and transcriptome profiles (e.g. 312 differentially expressed genes). Vitamin D3 supplementation did not affect training-associated changes for any of the main outcome domains, despite robust increases in [25(OH)D]serum (∆49% vs. placebo). No conditional effects were observed for COPD vs. healthy or pre-RCT [25(OH)D]serum . In secondary analyses, vitamin D3 affected expression of gene sets involved in vascular functions in muscle tissue and strength gains in participants with high fat mass, which advocates further study. CONCLUSIONS Vitamin D3 supplementation did not affect muscular responses to resistance training in older adults with or without COPD.
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Affiliation(s)
- Knut Sindre Mølmen
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Daniel Hammarström
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Karianne Pedersen
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Anne Cecilie Lian Lie
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Ragnvald B. Steile
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Håvard Nygaard
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Yusuf Khan
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
- Department of BiotechnologyInland Norway University of Applied SciencesHamarNorway
| | - Håvard Hamarsland
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Lise Koll
- Innlandet Hospital TrustLillehammerNorway
| | | | | | - Eirik Grindaker
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | | | - Daniel Buck
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Rafi Ahmad
- Department of BiotechnologyInland Norway University of Applied SciencesHamarNorway
- Institute of Clinical Medicine, Faculty of Health SciencesUiT – The Arctic University of NorwayTromsøNorway
| | - Tor A. Strand
- Innlandet Hospital TrustLillehammerNorway
- Centre for International HealthUniversity of BergenBergenNorway
| | - Bent R. Rønnestad
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
| | - Stian Ellefsen
- Section for Health and Exercise PhysiologyInland Norway University of Applied SciencesLillehammerNorway
- Innlandet Hospital TrustLillehammerNorway
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19
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Prasad V, Millay DP. Skeletal muscle fibers count on nuclear numbers for growth. Semin Cell Dev Biol 2021; 119:3-10. [PMID: 33972174 DOI: 10.1016/j.semcdb.2021.04.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/30/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023]
Abstract
Skeletal muscle cells are noteworthy for their syncytial nature, with each myofiber accumulating hundreds or thousands of nuclei derived from resident muscle stem cells (MuSCs). These nuclei are accrued through cell fusion, which is controlled by the two essential fusogens Myomaker and Myomerger that are transiently expressed within the myogenic lineage. While the absolute requirement of fusion for muscle development has been known for decades, the underlying need for the magnitude of multinucleation in muscle remains mysterious. Possible advantages of multinucleation include the potential it affords for transcriptional diversity within these massive cells, and as a means of increasing DNA content to support optimal cell size and function. In this article, we review recent advances that elucidate the relationship between myonuclear numbers and establishment of myofiber size, and discuss how this new information refines our understanding of the concept of myonuclear domains (MND), the cytoplasmic volumes that each resident myonucleus can support. Finally, we explore the potential consequences and costs of multinucleation and its impacts on myonuclear transcriptional reserve capacity, growth potential, myofiber size regulation, and muscle adaptability. We anticipate this report will not only serve to highlight the latest advances in the basic biology of syncytial muscle cells but also provide information to help design the next generation of therapeutic strategies to maintain muscle mass and function.
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Affiliation(s)
- Vikram Prasad
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Douglas P Millay
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
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20
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Grgic J, Garofolini A, Orazem J, Sabol F, Schoenfeld BJ, Pedisic Z. Effects of Resistance Training on Muscle Size and Strength in Very Elderly Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Sports Med 2021; 50:1983-1999. [PMID: 32740889 DOI: 10.1007/s40279-020-01331-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Effects of resistance training on muscle strength and hypertrophy are well established in adults and younger elderly. However, less is currently known about these effects in the very elderly (i.e., 75 years of age and older). OBJECTIVE To examine the effects of resistance training on muscle size and strength in very elderly individuals. METHODS Randomized controlled studies that explored the effects of resistance training in very elderly on muscle strength, handgrip strength, whole-muscle hypertrophy, and/or muscle fiber hypertrophy were included in the review. Meta-analyses of effect sizes (ESs) were used to analyze the data. RESULTS Twenty-two studies were included in the review. The meta-analysis found a significant effect of resistance training on muscle strength in the very elderly [difference in ES = 0.97; 95% confidence interval (CI) 0.50, 1.44; p = 0.001]. In a subgroup analysis that included only the oldest-old participants (80 + years of age), there was a significant effect of resistance training on muscle strength (difference in ES = 1.28; 95% CI 0.28, 2.29; p = 0.020). For handgrip strength, we found no significant difference between resistance training and control groups (difference in ES = 0.26; 95% CI - 0.02, 0.54; p = 0.064). For whole-muscle hypertrophy, there was a significant effect of resistance training in the very elderly (difference in ES = 0 30; 95% CI 0.10, 0.50; p = 0.013). We found no significant difference in muscle fiber hypertrophy between resistance training and control groups (difference in ES = 0.33; 95% CI - 0.67, 1.33; p = 0.266). There were minimal reports of adverse events associated with the training programs in the included studies. CONCLUSIONS We found that very elderly can increase muscle strength and muscle size by participating in resistance training programs. Resistance training was found to be an effective way to improve muscle strength even among the oldest-old.
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Affiliation(s)
- Jozo Grgic
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia.
| | | | - John Orazem
- School of Health Sciences, Human Services and Nursing, Lehman College, Bronx, USA
| | - Filip Sabol
- Fitness Academy, Zagreb, Croatia.,Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia
| | | | - Zeljko Pedisic
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia
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21
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Snijders T, Holwerda AM, van Loon LJC, Verdijk LB. Myonuclear content and domain size in small versus larger muscle fibres in response to 12 weeks of resistance exercise training in older adults. Acta Physiol (Oxf) 2021; 231:e13599. [PMID: 33314750 PMCID: PMC8047909 DOI: 10.1111/apha.13599] [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: 05/28/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
AIM To assess the relation between muscle fibre hypertrophy and myonuclear accretion in relatively small and large muscle fibre size clusters following prolonged resistance exercise training in older adults. METHODS Muscle biopsies were collected before and after 12 weeks of resistance exercise training in 40 healthy, older men (70 ± 3 years). All muscle fibres were ordered by size and categorized in four muscle fibre size clusters: 'Small': 2000-3999 µm2 , 'Moderate': 4000-5999 µm2 , 'Large': 6000-7999 µm2 and 'Largest': 8000-9999 µm2 . Changes in muscle fibre size cluster distribution were related to changes in muscle fibre size, myonuclear content and myonuclear domain size. RESULTS With training, the percentage of muscle fibres decreased in the Small (from 23 ± 12 to 17 ± 14%, P < .01) and increased in the Largest (from 11 ± 8 to 15 ± 10%, P < .01) muscle fibre size clusters. The decline in the percentage of Small muscle fibres was accompanied by an increase in overall myonuclear domain size (r = -.466, P = .002) and myonuclear content (r = -.390, P = .013). In contrast, the increase in the percentage of the Largest muscle fibres was accompanied by an overall increase in myonuclear content (r = .616, P < .001), but not in domain size. CONCLUSION Prolonged resistance-type exercise training induces a decline in the percentage of small as well as an increase in the percentage of the largest muscle fibres in older adults. Whereas the change in the percentage of small fibres is best predicted by an increase in overall myonuclear domain size, the change in the percentage of the largest fibres is associated with an overall increase in myonuclear content.
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Affiliation(s)
- Tim Snijders
- Human BiologySchool of Nutrition and Translational Research in Metabolism (NUTRIM)Maastricht UniversityMaastrichtThe Netherlands
| | - Andy M. Holwerda
- Human BiologySchool of Nutrition and Translational Research in Metabolism (NUTRIM)Maastricht UniversityMaastrichtThe Netherlands
| | - Luc J. C. van Loon
- Human BiologySchool of Nutrition and Translational Research in Metabolism (NUTRIM)Maastricht UniversityMaastrichtThe Netherlands
| | - Lex B. Verdijk
- Human BiologySchool of Nutrition and Translational Research in Metabolism (NUTRIM)Maastricht UniversityMaastrichtThe Netherlands
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22
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The efficacy of essential amino acid supplementation for augmenting dietary protein intake in older adults: implications for skeletal muscle mass, strength and function. Proc Nutr Soc 2020; 80:230-242. [PMID: 33315000 DOI: 10.1017/s0029665120008010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The primary aim of this review is to evaluate the efficacy of essential amino acid (EAA) supplementation as a strategy to increase dietary protein intake and improve muscle mass, strength and function in older adults. A sufficient daily protein intake is widely recognised to be fundamental for the successful management of sarcopenia in older undernourished adults. In practice, optimising protein intakes in older adults is complex, requiring consideration of the dose and amino acid composition (i.e. a complete EAA profile and abundant leucine content) of ingested protein on a per meal basis, alongside the age-related decline in appetite and the satiating properties of protein. Recent studies in older adults demonstrate that EAA-based supplements are non-satiating and can be administered alongside food to enhance the anabolic properties of a meal containing a suboptimal dose of protein; an effect magnified when combined with resistance exercise training. These findings support the notion that EAA supplementation could serve as an effective strategy to improve musculoskeletal health in older adults suffering from non-communicable diseases such as sarcopenia. Compliance is critical for the long-term success of complex interventions. Hence, aspects of palatability and desire to eat are important considerations regarding EAA supplementation. In conclusion, EAA-based supplements enriched with l-leucine offer an alternative strategy to whole protein sources to assist older adults in meeting protein recommendations. In practice, EAA supplements could be administered alongside meals of suboptimal protein content, or alternatively between meals on occasions when older adults achieve their per meal protein intake recommendations.
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23
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Fritzen AM, Thøgersen FD, Qadri KAN, Krag T, Sveen ML, Vissing J, Jeppesen TD. Preserved Capacity for Adaptations in Strength and Muscle Regulatory Factors in Elderly in Response to Resistance Exercise Training and Deconditioning. J Clin Med 2020; 9:jcm9072188. [PMID: 32664402 PMCID: PMC7408999 DOI: 10.3390/jcm9072188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/07/2020] [Accepted: 07/09/2020] [Indexed: 12/12/2022] Open
Abstract
Aging is related to an inevitable loss of muscle mass and strength. The mechanisms behind age-related loss of muscle tissue are not fully understood but may, among other things, be induced by age-related differences in myogenic regulatory factors. Resistance exercise training and deconditioning offers a model to investigate differences in myogenic regulatory factors that may be important for age-related loss of muscle mass and strength. Nine elderly (82 ± 7 years old) and nine young, healthy persons (22 ± 2 years old) participated in the study. Exercise consisted of six weeks of resistance training of the quadriceps muscle followed by eight weeks of deconditioning. Muscle biopsy samples before and after training and during the deconditioning period were analyzed for MyoD, myogenin, insulin-like growth-factor I receptor, activin receptor IIB, smad2, porin, and citrate synthase. Muscle strength improved with resistance training by 78% (95.0 ± 22.0 kg) in the elderly to a similar extent as in the young participants (83.5%; 178.2 ± 44.2 kg) and returned to baseline in both groups after eight weeks of deconditioning. No difference was seen in expression of muscle regulatory factors between elderly and young in response to exercise training and deconditioning. In conclusion, the capacity to gain muscle strength with resistance exercise training in elderly was not impaired, highlighting this as a potent tool to combat age-related loss of muscle function, possibly due to preserved regulation of myogenic factors in elderly compared with young muscle.
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Affiliation(s)
- Andreas Mæchel Fritzen
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
- Molecular Physiology Group, Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, DK-2100 Copenhagen, Denmark
- Correspondence: ; Tel.: +45-42633359
| | - Frank D. Thøgersen
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
| | - Khaled Abdul Nasser Qadri
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
| | - Thomas Krag
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
| | - Marie-Louise Sveen
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
- Novo Nordisk A/S, DK-2860 Søborg, Denmark
| | - John Vissing
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
| | - Tina D. Jeppesen
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, DK-2100 Copenhagen, Denmark; (F.D.T.); (K.A.N.Q.); (T.K.); (M.-L.S.); (J.V.); (T.D.J.)
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24
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Regular endurance exercise of overloaded muscle of young and old male mice does not attenuate hypertrophy and improves fatigue resistance. GeroScience 2020; 43:741-757. [PMID: 32643063 PMCID: PMC8110681 DOI: 10.1007/s11357-020-00224-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/26/2020] [Indexed: 12/16/2022] Open
Abstract
It has been observed that there is an inverse relationship between fiber size and oxidative capacity due to oxygen, ADP, and ATP diffusion limitations. We aimed to see if regular endurance exercise alongside a hypertrophic stimulus would lead to compromised adaptations to both, particularly in older animals. Here we investigated the effects of combining overload with regular endurance exercise in young (12 months) and old (26 months) male mice. The plantaris muscles of these mice were overloaded through denervation of synergists to induce hypertrophy and the mice ran on a treadmill for 30 min per day for 6 weeks. The hypertrophic response to overload was not blunted by endurance exercise, and the increase in fatigue resistance with endurance exercise was not reduced by overload. Old mice demonstrated less hypertrophy than young mice, which was associated with impaired angiogenesis and a reduction in specific tension. The data of this study suggest that combining endurance exercise and overload induces the benefits of both types of exercise without compromising adaptations to either. Additionally, the attenuated hypertrophic response to overload in old animals may be due to a diminished capacity for capillary growth.
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25
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Snijders T, Aussieker T, Holwerda A, Parise G, Loon LJC, Verdijk LB. The concept of skeletal muscle memory: Evidence from animal and human studies. Acta Physiol (Oxf) 2020; 229:e13465. [PMID: 32175681 PMCID: PMC7317456 DOI: 10.1111/apha.13465] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 03/05/2020] [Accepted: 03/10/2020] [Indexed: 12/18/2022]
Abstract
Within the current paradigm of the myonuclear domain theory, it is postulated that a linear relationship exists between muscle fibre size and myonuclear content. The myonuclear domain is kept (relatively) constant by adding additional nuclei (supplied by muscle satellite cells) during muscle fibre hypertrophy and nuclear loss (by apoptosis) during muscle fibre atrophy. However, data from recent animal studies suggest that myonuclei that are added to support muscle fibre hypertrophy are not lost within various muscle atrophy models. Such myonuclear permanence has been suggested to constitute a mechanism allowing the muscle fibre to (re)grow more efficiently during retraining, a phenomenon referred to as "muscle memory." The concept of "muscle memory by myonuclear permanence" has mainly been based on data attained from rodent experimental models. Whether the postulated mechanism also holds true in humans remains largely ambiguous. Nevertheless, there are several studies in humans that provide evidence to potentially support or contradict (parts of) the muscle memory hypothesis. The goal of the present review was to discuss the evidence for the existence of "muscle memory" in both animal and human models of muscle fibre hypertrophy as well as atrophy. Furthermore, to provide additional insight in the potential presence of muscle memory by myonuclear permanence in humans, we present new data on previously performed exercise training studies. Finally, suggestions for future research are provided to establish whether muscle memory really exists in humans.
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Affiliation(s)
- Tim Snijders
- Department of Human Biology NUTRIM School of Nutrition and Translational Research in Metabolism Maastricht University Maastricht the Netherlands
| | - Thorben Aussieker
- Department of Human Biology NUTRIM School of Nutrition and Translational Research in Metabolism Maastricht University Maastricht the Netherlands
| | - Andy Holwerda
- Department of Human Biology NUTRIM School of Nutrition and Translational Research in Metabolism Maastricht University Maastricht the Netherlands
| | - Gianni Parise
- Department of Kinesiology and Medical Physics & Applied Radiation Sciences McMaster University Hamilton ON Canada
| | - Luc J. C. Loon
- Department of Human Biology NUTRIM School of Nutrition and Translational Research in Metabolism Maastricht University Maastricht the Netherlands
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26
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Zhao Y, Shen F, Gong M, Jin L, Ren X, Liu K, Lu J. Lifelong treadmill training improves muscle function detected by a modified grip strength test during aging in BALB/c mice. Life Sci 2020; 251:117603. [DOI: 10.1016/j.lfs.2020.117603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/15/2020] [Accepted: 03/24/2020] [Indexed: 12/31/2022]
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27
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Hansen SK, Ratzer J, Nielsen JL, Suetta C, Karlsen A, Kvorning T, Frandsen U, Aagaard P. Effects of alternating blood flow restricted training and heavy-load resistance training on myofiber morphology and mechanical muscle function. J Appl Physiol (1985) 2020; 128:1523-1532. [PMID: 32324471 DOI: 10.1152/japplphysiol.00015.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
To investigate if short-term block-structured training consisting of alternating weeks of blood flow restricted low-load resistance training (BFR-RT) and conventional free-flow heavy-load resistance training (HL-RT) leads to superior gains in mechanical muscle function, myofiber size, and satellite cell (SC) content and myonuclear number compared with HL-RT alone. Eighteen active young participants (women/men: 5/13, 23 ± 1.2 yr) were randomized to 6 wk (22 sessions) of lower limb HL-RT [70-90% one repetition maximum (1-RM)] (HRT, n = 9) or block-structured training alternating weekly between BFR-RT (20% 1-RM) and HL-RT (BFR-HRT, n = 9). Maximal isometric knee extensor strength (MVC) and muscle biopsies (VL) were obtained pre- and posttraining to examine changes in muscle strength, myofiber cross-sectional area (CSA), myonuclear (MN) number, and SC content. MVC increased in both training groups (BFR-HRT: +12%, HRT: +7%; P < 0.05). Type II myofiber CSA increased similarly (+16%) in BFR-HRT and HRT (P < 0.05), while gains in type I CSA were observed following HRT only (+12%, P < 0.05). In addition, myonuclear number remained unchanged, whereas SC content increased in type II myofibers following HRT (+59%, P < 0.05). Short-term alternating BFR-RT and HL-RT did not produce superior gains in muscle strength or myofiber size compared with HL-RT alone. Noticeably, however, conventional HL-RT could be periodically replaced by low-load BFR-RT without compromising training-induced gains in maximal muscle strength and type II myofiber size, respectively.NEW & NOTEWORTHY The present data demonstrate that periodically substituting heavy-load resistance training (HL-RT) with low-load blood flow restricted resistance training (BFR-RT) leads to similar gains in type II myofiber CSA and muscle strength as achieved by HL-RT alone. Furthermore, we have for the first time evaluated myonuclear content and myonuclear domain size before and after training intervention across separate fiber size clusters and found no within-cluster changes for these parameters with training.
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Affiliation(s)
- S K Hansen
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.,Geriatric Research Unit, Bispebjerg-Frederiksberg University Hospital, Copenhagen, Denmark
| | - J Ratzer
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - J L Nielsen
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - C Suetta
- Geriatric Research Unit, Bispebjerg-Frederiksberg University Hospital, Copenhagen, Denmark.,Geriatric Research Unit, Herlev-Gentofte University Hospital, Copenhagen, Denmark
| | - A Karlsen
- Institute of Sports Medicine Copenhagen, Denmark.,Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Center of Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - T Kvorning
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.,Team Danmark (The Danish Elite Sport Institution), Brøndby, Denmark
| | - U Frandsen
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - P Aagaard
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
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28
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The effect of resistance training, detraining and retraining on muscle strength and power, myofibre size, satellite cells and myonuclei in older men. Exp Gerontol 2020; 133:110860. [DOI: 10.1016/j.exger.2020.110860] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 01/05/2023]
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29
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Englund DA, Murach KA, Dungan CM, Figueiredo VC, Vechetti IJ, Dupont-Versteegden EE, McCarthy JJ, Peterson CA. Depletion of resident muscle stem cells negatively impacts running volume, physical function, and muscle fiber hypertrophy in response to lifelong physical activity. Am J Physiol Cell Physiol 2020; 318:C1178-C1188. [PMID: 32320286 DOI: 10.1152/ajpcell.00090.2020] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
To date, studies that have aimed to investigate the role of satellite cells during adult skeletal muscle adaptation and hypertrophy have utilized a nontranslational stimulus and/or have been performed over a relatively short time frame. Although it has been shown that satellite cell depletion throughout adulthood does not drive skeletal muscle loss in sedentary mice, it remains unknown how satellite cells participate in skeletal muscle adaptation to long-term physical activity. The current study was designed to determine whether reduced satellite cell content throughout adulthood would influence the transcriptome-wide response to physical activity and diminish the adaptive response of skeletal muscle. We administered vehicle or tamoxifen to adult Pax7-diphtheria toxin A (DTA) mice to deplete satellite cells and assigned them to sedentary or wheel-running conditions for 13 mo. Satellite cell depletion throughout adulthood reduced balance and coordination, overall running volume, and the size of muscle proprioceptors (spindle fibers). Furthermore, satellite cell participation was necessary for optimal muscle fiber hypertrophy but not adaptations in fiber type distribution in response to lifelong physical activity. Transcriptome-wide analysis of the plantaris and soleus revealed that satellite cell function is muscle type specific; satellite cell-dependent myonuclear accretion was apparent in oxidative muscles, whereas initiation of G protein-coupled receptor (GPCR) signaling in the glycolytic plantaris may require satellite cells to induce optimal adaptations to long-term physical activity. These findings suggest that satellite cells play a role in preserving physical function during aging and influence muscle adaptation during sustained periods of physical activity.
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Affiliation(s)
- Davis A Englund
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Kevin A Murach
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Cory M Dungan
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Vandré C Figueiredo
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - Ivan J Vechetti
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky.,Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Esther E Dupont-Versteegden
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
| | - John J McCarthy
- Center for Muscle Biology, University of Kentucky, Lexington, Kentucky.,Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Charlotte A Peterson
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, Kentucky.,Center for Muscle Biology, University of Kentucky, Lexington, Kentucky
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30
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Key Components of Human Myofibre Denervation and Neuromuscular Junction Stability are Modulated by Age and Exercise. Cells 2020; 9:cells9040893. [PMID: 32268508 PMCID: PMC7226801 DOI: 10.3390/cells9040893] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/25/2020] [Accepted: 04/03/2020] [Indexed: 01/26/2023] Open
Abstract
The decline in muscle mass and function with age is partly caused by a loss of muscle fibres through denervation. The purpose of this study was to investigate the potential of exercise to influence molecular targets involved in neuromuscular junction (NMJ) stability in healthy elderly individuals. Participants from two studies (one group of 12 young and 12 elderly females and another group of 25 elderly males) performed a unilateral bout of resistance exercise. Muscle biopsies were collected at 4.5 h and up to 7 days post exercise for tissue analysis and cell culture. Molecular targets related to denervation and NMJ stability were analysed by immunohistochemistry and real-time reverse transcription polymerase chain reaction. In addition to a greater presence of denervated fibres, the muscle samples and cultured myotubes from the elderly individuals displayed altered gene expression levels of acetylcholine receptor (AChR) subunits. A single bout of exercise induced general changes in AChR subunit gene expression within the biopsy sampling timeframe, suggesting a sustained plasticity of the NMJ in elderly individuals. These data support the role of exercise in maintaining NMJ stability, even in elderly inactive individuals. Furthermore, the cell culture findings suggest that the transcriptional capacity of satellite cells for AChR subunit genes is negatively affected by ageing.
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31
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Karlsen A, Soendenbroe C, Malmgaard-Clausen NM, Wagener F, Moeller CE, Senhaji Z, Damberg K, Andersen JL, Schjerling P, Kjaer M, Mackey AL. Preserved capacity for satellite cell proliferation, regeneration, and hypertrophy in the skeletal muscle of healthy elderly men. FASEB J 2020; 34:6418-6436. [PMID: 32167202 DOI: 10.1096/fj.202000196r] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 01/30/2023]
Abstract
Blunted muscle hypertrophy and impaired regeneration with aging have been partly attributed to satellite cell (SC) dysfunction. However, true muscle regeneration has not yet been studied in elderly individuals. To investigate this, muscle injury was induced by 200 electrically stimulated (ES) eccentric contractions of the vastus lateralis (VL) of one leg in seven young (20-31 years) and 19 elderly men (60-73 years). This was followed by 13 weeks of resistance training (RT) for both legs to investigate the capacity for hypertrophy. Muscle biopsies were collected Pre- and Post-RT, and 9 days after ES, for immunohistochemistry and RT-PCR. Hypertrophy was assessed by MRI, DEXA, and immunohistochemistry. Overall, surprisingly comparable responses were observed between the young and elderly. Nine days after ES, Pax7+ SC number had doubled (P < .05), alongside necrosis and substantial changes in expression of genes related to matrix, myogenesis, and innervation (P < .05). Post-RT, VL cross-sectional area had increased in both legs (~15%, P < .05) and SCs/type II fiber had increased ~2-4 times more with ES+RT vs RT alone (P < .001). Together these novel findings demonstrate "youthful" regeneration and hypertrophy responses in human elderly muscle. Furthermore, boosting SC availability in healthy elderly men does not enhance the subsequent muscle hypertrophy response to RT.
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Affiliation(s)
- Anders Karlsen
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Casper Soendenbroe
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Nikolaj M Malmgaard-Clausen
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Frederik Wagener
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark
| | - Casper Emil Moeller
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark
| | - Zouhir Senhaji
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark
| | - Kristine Damberg
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jesper Løvind Andersen
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Peter Schjerling
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Michael Kjaer
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Abigail L Mackey
- Department of Orthopaedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
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32
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Sanz G, Martínez-Aranda LM, Tesch PA, Fernandez-Gonzalo R, Lundberg TR. Muscle2View, a CellProfiler pipeline for detection of the capillary-to-muscle fiber interface and high-content quantification of fiber type-specific histology. J Appl Physiol (1985) 2019; 127:1698-1709. [DOI: 10.1152/japplphysiol.00257.2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Because manual immunohistochemical analysis of features such as skeletal muscle fiber typing, capillaries, myonuclei, and fiber size-related parameters is time consuming and prone to user subjectivity, automatic computational methods could allow for faster and more objective evaluation. Here, we developed Muscle2View, a free CellProfiler-based pipeline that integrates all key fiber-morphological variables, including the novel quantification of the capillary-to-fiber interface, in one single tool. Provided that the images are of sufficient quality and the settings are configured for the specific study, the pipeline allows for automatic and unsupervised analysis of fiber borders, myonuclei, capillaries, and morphometric parameters in a fiber type-specific manner from large batches of images in <10 min/tissue sample. The novel identification of the capillary-to-fiber interface allowed for the calculation of microvascular factors such as capillary contacts (CC), individual capillary-to-fiber ratio (C/Fi), and capillary-to-fiber perimeter exchange (CFPE) index. When comparing the Muscle2View pipeline to manual or semiautomatic analysis, overall the results revealed strong correlations. For several variables, however, there were differences (5–15%) between values computed by manual counting and Muscle2View, suggesting that the methods should not necessarily be used interchangeably. Collectively, we demonstrate that the Muscle2View pipeline can provide unbiased and high-content analysis of muscle cross-sectional immunohistochemistry images. In addition to the classical morphological measurements, the Muscle2View can identify the complex capillary-to-fiber network and myonuclear density in a fiber type-specific manner. This robust analysis is done in one single run within a user-friendly and flexible environment based on the free and widely used image software CellProfiler. NEW & NOTEWORTHY Here, we developed a freely available CellProfiler-based pipeline termed Muscle2View, which provides unbiased, high-content analysis of muscle cross-sectional immunohistochemistry images. In addition to fiber typing, myonuclei counting, and the quantification of fiber type-specific morphological measurements, the Muscle2View pipeline can identify the complex capillary-to-fiber network from a batch of images within minutes. Thus, the Muscle2View is a viable tool for researchers aiming to quantify immunohistochemical variables from skeletal muscle biopsies.
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Affiliation(s)
- Gema Sanz
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Gnomics, Murcia, Spain
| | - Luis Manuel Martínez-Aranda
- Faculty of Sport, Neuroscience of Human Movement Research Group (Neuromove), Catholic University of San Antonio, Murcia, Spain
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Per A. Tesch
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Rodrigo Fernandez-Gonzalo
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
| | - Tommy R. Lundberg
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, and Unit of Clinical Physiology, Karolinska University Hospital, Stockholm, Sweden
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33
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Lundberg TR, Gustafsson T. Fibre hypertrophy, satellite cell and myonuclear adaptations to resistance training: Have very old individuals reached the ceiling for muscle fibre plasticity? Acta Physiol (Oxf) 2019; 227:e13287. [PMID: 31009166 DOI: 10.1111/apha.13287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 04/17/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Tommy R. Lundberg
- Department of Laboratory Medicine, Division of Clinical Physiology Karolinska Institutet Stockholm Sweden
- Unit of Clinical Physiology Karolinska University Hospital Stockholm Sweden
| | - Thomas Gustafsson
- Department of Laboratory Medicine, Division of Clinical Physiology Karolinska Institutet Stockholm Sweden
- Unit of Clinical Physiology Karolinska University Hospital Stockholm Sweden
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