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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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Piétri-Rouxel F, Falcone S, Traoré M. [GDF5: a therapeutic candidate for combating sarcopenia]. Med Sci (Paris) 2023; 39 Hors série n° 1:47-53. [PMID: 37975770 DOI: 10.1051/medsci/2023143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023] Open
Abstract
Sarcopenia is a complex age-related muscular disease affecting 10 to 16 % of people over 65 years old. It is characterized by excessive loss of muscle mass and strength. Despite a plethora of studies aimed at understanding the physiological mechanisms underlying this pathology, the pathophysiology of sarcopenia remains poorly understood. To date, there is no pharmacological treatment for this disease. In this context, our team develop therapeutic approaches based on the GDF5 protein to counteract the loss of muscle mass and function in various pathological conditions, including sarcopenia. After deciphering one of the molecular mechanisms governing GDF5 expression, we have demonstrated the therapeutic potential of this protein in the preservation of muscle mass and strength in aged mice.
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Affiliation(s)
- France Piétri-Rouxel
- Sorbonne Université, INSERM, Institut de Myologie, Centre de Recherche en Myologie, F-75013 Paris, France
| | - Sestina Falcone
- Sorbonne Université, INSERM, Institut de Myologie, Centre de Recherche en Myologie, F-75013 Paris, France
| | - Massiré Traoré
- Sorbonne Université, INSERM, Institut de Myologie, Centre de Recherche en Myologie, F-75013 Paris, France
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Shavlakadze T, Xiong K, Mishra S, McEwen C, Gadi A, Wakai M, Salmon H, Stec MJ, Negron N, Ni M, Wei Y, Atwal GS, Bai Y, Glass DJ. Age-related gene expression signatures from limb skeletal muscles and the diaphragm in mice and rats reveal common and species-specific changes. Skelet Muscle 2023; 13:11. [PMID: 37438807 DOI: 10.1186/s13395-023-00321-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/13/2023] [Indexed: 07/14/2023] Open
Abstract
BACKGROUND As a result of aging, skeletal muscle undergoes atrophy and a decrease in function. This age-related skeletal muscle weakness is known as "sarcopenia". Sarcopenia is part of the frailty observed in humans. In order to discover treatments for sarcopenia, it is necessary to determine appropriate preclinical models and the genes and signaling pathways that change with age in these models. METHODS AND RESULTS To understand the changes in gene expression that occur as a result of aging in skeletal muscles, we generated a multi-time-point gene expression signature throughout the lifespan of mice and rats, as these are the most commonly used species in preclinical research and intervention testing. Gastrocnemius, tibialis anterior, soleus, and diaphragm muscles from male and female C57Bl/6J mice and male Sprague Dawley rats were analyzed at ages 6, 12, 18, 21, 24, and 27 months, plus an additional 9-month group was used for rats. More age-related genes were identified in rat skeletal muscles compared with mice; this was consistent with the finding that rat muscles undergo more robust age-related decline in mass. In both species, pathways associated with innate immunity and inflammation linearly increased with age. Pathways linked with extracellular matrix remodeling were also universally downregulated. Interestingly, late downregulated pathways were exclusively found in the rat limb muscles and these were linked to metabolism and mitochondrial respiration; this was not seen in the mouse. CONCLUSIONS This extensive, side-by-side transcriptomic profiling shows that the skeletal muscle in rats is impacted more by aging compared with mice, and the pattern of decline in the rat may be more representative of the human. The observed changes point to potential therapeutic interventions to avoid age-related decline in skeletal muscle function.
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Affiliation(s)
- Tea Shavlakadze
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Kun Xiong
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Shawn Mishra
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Corissa McEwen
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Abhilash Gadi
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Matthew Wakai
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Hunter Salmon
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Michael J Stec
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Nicole Negron
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Min Ni
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Yi Wei
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Gurinder S Atwal
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Yu Bai
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - David J Glass
- Regeneron Pharmaceuticals, 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA.
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Use of a novel technique to assess impact of age-related denervation on mouse soleus muscle function. Biogerontology 2023; 24:377-390. [PMID: 36790689 PMCID: PMC10147802 DOI: 10.1007/s10522-023-10021-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/26/2023] [Indexed: 02/16/2023]
Abstract
Denervation contributes to loss of force-generating capacity in aged skeletal muscles, but problems with quantification of denervated fibers mean the precise impact of denervation on muscle function remains unclear. This study therefore looked to develop a reliable assay for identifying denervated muscle fibers, and used this to explore the impact of denervation on age-related force-generation in mouse skeletal muscle. Thirteen young (6-month-old) and 10 old (24-months-old) C57Bl/6 J female mice were utilized. Anaesthetized mice were infused with the fluorescent deoxyglucose analog 2[N-(7-nitrobenz-2-oxa-1,2-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG) and the tibial nerve was repeatedly stimulated to label active skeletal muscle fibers by activity-dependent uptake of 2-NBDG. Data on muscle force generation were acquired as part of the stimulation routine. Labeled muscles were removed, snap frozen, sectioned, and slide mounted. Sections were imaged to show accumulation of 2-NBDG in activated fibers and lack of 2-NBDG accumulation in quiescent (denervated) fibers, then processed using immunohistochemistry to allow collection of data on fiber number and morphology. Soleus muscles from older mice had nine times as many denervated fibers as those from young mice (average n = 36 vs 4, old vs young). Older muscles developed significantly more passive force and less specific force, but denervation only partly accounted for age-related deficits in specific force. Further investigations are required to definitively identify contributors to the decrease in force generation that remain unaccounted for.
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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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Cheng KYK, Bao Z, Long Y, Liu C, Huang T, Cui C, Chow SKH, Wong RMY, Cheung WH. Sarcopenia and Ageing. Subcell Biochem 2023; 103:95-120. [PMID: 37120466 DOI: 10.1007/978-3-031-26576-1_6] [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: 05/01/2023]
Abstract
Musculoskeletal ageing is a major health challenge as muscles and bones constitute around 55-60% of body weight. Ageing muscles will result in sarcopenia that is characterized by progressive and generalized loss of skeletal muscle mass and strength with a risk of adverse outcomes. In recent years, a few consensus panels provide new definitions for sarcopenia. It was officially recognized as a disease in 2016 with an ICD-10-CM disease code, M62.84, in the International Classification of Diseases (ICD). With the new definitions, there are many studies emerging to investigate the pathogenesis of sarcopenia, exploring new interventions to treat sarcopenia and evaluating the efficacy of combination treatments for sarcopenia. The scope of this chapter is to summarize and appraise the evidence in terms of (1) clinical signs, symptoms, screening, and diagnosis, (2) pathogenesis of sarcopenia with emphasis on mitochondrial dysfunction, intramuscular fat infiltration and neuromuscular junction deterioration, and (3) current treatments with regard to physical exercises and nutritional supplement.
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Affiliation(s)
- Keith Yu-Kin Cheng
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Zhengyuan Bao
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yufeng Long
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Chaoran Liu
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Tao Huang
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Can Cui
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Simon Kwoon-Ho Chow
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
- Department of Orthopaedic Surgery, Stanford University, Stanford, CA, USA
| | - Ronald Man Yeung Wong
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Wing-Hoi Cheung
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China.
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Davis LA, Fogarty MJ, Brown A, Sieck GC. Structure and Function of the Mammalian Neuromuscular Junction. Compr Physiol 2022; 12:3731-3766. [PMID: 35950651 PMCID: PMC10461538 DOI: 10.1002/cphy.c210022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The mammalian neuromuscular junction (NMJ) comprises a presynaptic terminal, a postsynaptic receptor region on the muscle fiber (endplate), and the perisynaptic (terminal) Schwann cell. As with any synapse, the purpose of the NMJ is to transmit signals from the nervous system to muscle fibers. This neural control of muscle fibers is organized as motor units, which display distinct structural and functional phenotypes including differences in pre- and postsynaptic elements of NMJs. Motor units vary considerably in the frequency of their activation (both motor neuron discharge rate and duration/duty cycle), force generation, and susceptibility to fatigue. For earlier and more frequently recruited motor units, the structure and function of the activated NMJs must have high fidelity to ensure consistent activation and continued contractile response to sustain vital motor behaviors (e.g., breathing and postural balance). Similarly, for higher force less frequent behaviors (e.g., coughing and jumping), the structure and function of recruited NMJs must ensure short-term reliable activation but not activation sustained for a prolonged period in which fatigue may occur. The NMJ is highly plastic, changing structurally and functionally throughout the life span from embryonic development to old age. The NMJ also changes under pathological conditions including acute and chronic disease. Such neuroplasticity often varies across motor unit types. © 2022 American Physiological Society. Compr Physiol 12:1-36, 2022.
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Affiliation(s)
- Leah A. Davis
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Matthew J. Fogarty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Alyssa Brown
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Gary C. Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
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Ubiquitin Ligases in Longevity and Aging Skeletal Muscle. Int J Mol Sci 2022; 23:ijms23147602. [PMID: 35886949 PMCID: PMC9315556 DOI: 10.3390/ijms23147602] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 12/07/2022] Open
Abstract
The development and prevalence of diseases associated with aging presents a global health burden on society. One hallmark of aging is the loss of proteostasis which is caused in part by alterations to the ubiquitin-proteasome system (UPS) and lysosome-autophagy system leading to impaired function and maintenance of mass in tissues such as skeletal muscle. In the instance of skeletal muscle, the impairment of function occurs early in the aging process and is dependent on proteostatic mechanisms. The UPS plays a pivotal role in degradation of misfolded and aggregated proteins. For the purpose of this review, we will discuss the role of the UPS system in the context of age-related loss of muscle mass and function. We highlight the significant role that E3 ubiquitin ligases play in the turnover of key components (e.g., mitochondria and neuromuscular junction) essential to skeletal muscle function and the influence of aging. In addition, we will briefly discuss the contribution of the UPS system to lifespan. By understanding the UPS system as part of the proteostasis network in age-related diseases and disorders such as sarcopenia, new discoveries can be made and new interventions can be developed which will preserve muscle function and maintain quality of life with advancing age.
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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: 0] [Impact Index Per Article: 0] [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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10
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Jones EJ, Chiou S, Atherton PJ, Phillips BE, Piasecki M. Ageing and exercise-induced motor unit remodelling. J Physiol 2022; 600:1839-1849. [PMID: 35278221 PMCID: PMC9314090 DOI: 10.1113/jp281726] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 02/14/2022] [Indexed: 11/08/2022] Open
Abstract
A motor unit (MU) comprises the neuron cell body, its corresponding axon and each of the muscle fibres it innervates. Many studies highlight age-related reductions in the number of MUs, yet the ability of a MU to undergo remodelling and to expand to rescue denervated muscle fibres is also a defining feature of MU plasticity. Remodelling of MUs involves two coordinated processes: (i) axonal sprouting and new branching growth from adjacent surviving neurons, and (ii) the formation of key structures around the neuromuscular junction to resume muscle-nerve communication. These processes rely on neurotrophins and coordinated signalling in muscle-nerve interactions. To date, several neurotrophins have attracted focus in animal models, including brain-derived neurotrophic factor and insulin-like growth factors I and II. Exercise in older age has demonstrated benefits in multiple physiological systems including skeletal muscle, yet evidence suggests this may also extend to peripheral MU remodelling. There is, however, a lack of research in humans due to methodological limitations which are easily surmountable in animal models. To improve mechanistic insight of the effects of exercise on MU remodelling with advancing age, future research should focus on combining methodological approaches to explore the in vivo physiological function of the MU alongside alterations of the localised molecular environment.
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Affiliation(s)
- Eleanor J. Jones
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Shin‐Yi Chiou
- School of SportExercise, and Rehabilitation Sciences, MRC‐Versus Arthritis Centre for Musculoskeletal Ageing Research, Centre for Human Brain HealthUniversity of BirminghamBirminghamUK
| | - Philip J. Atherton
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Bethan E. Phillips
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Mathew Piasecki
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
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11
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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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12
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Lu W, Li JP, Jiang ZD, Yang L, Liu XZ. Effects of targeted muscle reinnervation on spinal cord motor neurons in rats following tibial nerve transection. Neural Regen Res 2022; 17:1827-1832. [PMID: 35017445 PMCID: PMC8820695 DOI: 10.4103/1673-5374.332153] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Targeted muscle reinnervation (TMR) is a surgical procedure used to transfer residual peripheral nerves from amputated limbs to targeted muscles, which allows the target muscles to become sources of motor control information for function reconstruction. However, the effect of TMR on injured motor neurons is still unclear. In this study, we aimed to explore the effect of hind limb TMR surgery on injured motor neurons in the spinal cord of rats after tibial nerve transection. We found that the reduction in hind limb motor function and atrophy in mice caused by tibial nerve transection improved after TMR. TMR enhanced nerve regeneration by increasing the number of axons and myelin sheath thickness in the tibial nerve, increasing the number of anterior horn motor neurons, and increasing the number of choline acetyltransferase-positive cells and immunofluorescence intensity of synaptophysin in rat spinal cord. Our findings suggest that TMR may enable the reconnection of residual nerve fibers to target muscles, thus restoring hind limb motor function on the injured side.
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Affiliation(s)
- Wei Lu
- Department of Human Anatomy, School of Basic Medical Scinences, Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region; Department of Human Anatomy, Zhuhai Campus of Zunyi Medical University, Zhuhai, Guangdong Province, China
| | - Jian-Ping Li
- Department of Human Anatomy, Zhuhai Campus of Zunyi Medical University, Zhuhai, Guangdong Province, China
| | - Zhen-Dong Jiang
- Department of Human Anatomy, Zhuhai Campus of Zunyi Medical University, Zhuhai, Guangdong Province, China
| | - Lin Yang
- Department of Human Anatomy, Zhuhai Campus of Zunyi Medical University, Zhuhai, Guangdong Province, China
| | - Xue-Zheng Liu
- Department of Human Anatomy, School of Basic Medical Scinences, Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, China
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13
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Moreira-Pais A, Ferreira R, Oliveira PA, Duarte JA. A neuromuscular perspective of sarcopenia pathogenesis: deciphering the signaling pathways involved. GeroScience 2022; 44:1199-1213. [PMID: 34981273 DOI: 10.1007/s11357-021-00510-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/26/2021] [Indexed: 12/18/2022] Open
Abstract
The escalation of life expectancy is accompanied by an increase in the prevalence of age-related conditions, such as sarcopenia. Sarcopenia, a muscle condition defined by low muscle strength, muscle quality or quantity, and physical performance, has a high prevalence among the elderly and is associated to increased mortality. The neuromuscular system has been emerging as a key contributor to sarcopenia pathogenesis. Indeed, the age-related degeneration of the neuromuscular junction (NMJ) function and structure may contribute to the loss of muscle strength and ultimately to the loss of muscle mass that characterize sarcopenia. The present mini-review discusses important signaling pathways involved in the function and maintenance of the NMJ, giving emphasis to the ones that might contribute to sarcopenia pathogenesis. Some conceivable biomarkers, such as C-terminal agrin fragment (CAF) and brain-derived neurotrophic factor (BDNF), and therapeutic targets, namely acetylcholine and calcitonin gene-related peptide (CGRP), can be retrieved, making way to future studies to validate their clinical use.
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Affiliation(s)
- Alexandra Moreira-Pais
- CIAFEL, Faculty of Sport, University of Porto, Dr. Plácido da Costa 91, 4200-450, Porto, Portugal. .,LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal. .,Centre for Research and Technology of Agro Environmental and Biological Sciences (CITAB), Inov4Agro, University of Trás-Os-Montes and Alto Douro (UTAD), Quinta de Prados, 5000-801, Vila Real, Portugal.
| | - Rita Ferreira
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Paula A Oliveira
- Centre for Research and Technology of Agro Environmental and Biological Sciences (CITAB), Inov4Agro, University of Trás-Os-Montes and Alto Douro (UTAD), Quinta de Prados, 5000-801, Vila Real, Portugal
| | - José A Duarte
- CIAFEL, Faculty of Sport, University of Porto, Dr. Plácido da Costa 91, 4200-450, Porto, Portugal.,TOXRUN - Toxicology Research Unit, University Institute of Health Sciences, CESPU, CRL, Gandra, Portugal
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14
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Early Deconditioning of Human Skeletal Muscles and the Effects of a Thigh Cuff Countermeasure. Int J Mol Sci 2021; 22:ijms222112064. [PMID: 34769492 PMCID: PMC8584355 DOI: 10.3390/ijms222112064] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/29/2021] [Accepted: 10/30/2021] [Indexed: 01/12/2023] Open
Abstract
Muscle deconditioning is a major consequence of a wide range of conditions from spaceflight to a sedentary lifestyle, and occurs as a result of muscle inactivity, leading to a rapid decrease in muscle strength, mass, and oxidative capacity. The early changes that appear in the first days of inactivity must be studied to determine effective methods for the prevention of muscle deconditioning. To evaluate the mechanisms of muscle early changes and the vascular effect of a thigh cuff, a five-day dry immersion (DI) experiment was conducted by the French Space Agency at the MEDES Space Clinic (Rangueil, Toulouse). Eighteen healthy males were recruited and divided into a control group and a thigh cuff group, who wore a thigh cuff at 30 mmHg. All participants underwent five days of DI. Prior to and at the end of the DI, the lower limb maximal strength was measured and muscle biopsies were collected from the vastus lateralis muscle. Five days of DI resulted in muscle deconditioning in both groups. The maximal voluntary isometric contraction of knee extension decreased significantly. The muscle fiber cross-sectional area decreased significantly by 21.8%, and the protein balance seems to be impaired, as shown by the reduced activation of the mTOR pathway. Measurements of skinned muscle fibers supported these results and potential changes in oxidative capacity were highlighted by a decrease in PGC1-α levels. The use of the thigh cuff did not prevent muscle deconditioning or impact muscle function. These results suggest that the major effects of muscle deconditioning occur during the first few days of inactivity, and countermeasures against muscle deconditioning should target this time period. These results are also relevant for the understanding of muscle weakness induced by muscle diseases, aging, and patients in intensive care.
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15
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Pratt J, De Vito G, Narici M, Boreham C. Neuromuscular Junction Aging: A Role for Biomarkers and Exercise. J Gerontol A Biol Sci Med Sci 2021; 76:576-585. [PMID: 32832976 DOI: 10.1093/gerona/glaa207] [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] [Received: 05/22/2020] [Indexed: 12/13/2022] Open
Abstract
Age-related skeletal muscle degradation known as "sarcopenia" exerts considerable strain on public health systems globally. While the pathogenesis of such atrophy is undoubtedly multifactorial, disruption at the neuromuscular junction (NMJ) has recently gained traction as a key explanatory factor. The NMJ, an essential communicatory link between nerve and muscle, undergoes profound changes with advancing age. Ascertaining whether such changes potentiate the onset of sarcopenia would be paramount in facilitating a timely implementation of targeted therapeutic strategies. Hence, there is a growing level of importance to further substantiate the effects of age on NMJs, in parallel with developing measures to attenuate such changes. As such, this review aimed to establish the current standpoint on age-related NMJ deterioration and consequences for skeletal muscle, while illuminating a role for biomarkers and exercise in ameliorating these alterations. Recent insights into the importance of key biomarkers for NMJ stability are provided, while the stimulative benefits of exercise in preserving NMJ function are demonstrated. Further elucidation of the diagnostic and prognostic relevance of biomarkers, coupled with the therapeutic benefits of regular exercise may be crucial in combating age-related NMJ and skeletal muscle degradation.
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Affiliation(s)
- Jedd Pratt
- Institute for Sport and Health, University College Dublin, Ireland.,Genuity Science, Dublin, Ireland
| | - Giuseppe De Vito
- Department of Biomedical Sciences, CIR-Myo Myology Centre, Neuromuscular Physiology Laboratory, University of Padua, Italy
| | - Marco Narici
- Department of Biomedical Sciences, CIR-Myo Myology Centre, Neuromuscular Physiology Laboratory, University of Padua, Italy
| | - Colin Boreham
- Institute for Sport and Health, University College Dublin, Ireland
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16
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Quinlan JI, Franchi MV, Gharahdaghi N, Badiali F, Francis S, Hale A, Phillips BE, Szewczyk N, Greenhaff PL, Smith K, Maganaris C, Atherton PJ, Narici MV. Muscle and tendon adaptations to moderate load eccentric vs. concentric resistance exercise in young and older males. GeroScience 2021; 43:1567-1584. [PMID: 34196903 PMCID: PMC8492846 DOI: 10.1007/s11357-021-00396-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/27/2021] [Indexed: 02/07/2023] Open
Abstract
Resistance exercise training (RET) is well-known to counteract negative age-related changes in both muscle and tendon tissue. Traditional RET consists of both concentric (CON) and eccentric (ECC) contractions; nevertheless, isolated ECC contractions are metabolically less demanding and, thus, may be more suitable for older populations. However, whether submaximal (60% 1RM) CON or ECC contractions differ in their effectiveness is relatively unknown. Further, whether the time course of muscle and tendon adaptations differs to the above is also unknown. Therefore, this study aimed to establish the time course of muscle and tendon adaptations to submaximal CON and ECC RET. Twenty healthy young (24.5 ± 5.1 years) and 17 older males (68.1 ± 2.4 years) were randomly allocated to either isolated CON or ECC RET which took place 3/week for 8 weeks. Tendon biomechanical properties, muscle architecture and maximal voluntary contraction were assessed every 2 weeks and quadriceps muscle volume every 4 weeks. Positive changes in tendon Young's modulus were observed after 4 weeks in all groups after which adaptations in young males plateaued but continued to increase in older males, suggesting a dampened rate of adaptation with age. However, both CON and ECC resulted in similar overall changes in tendon Young's modulus, in all groups. Muscle hypertrophy and strength increases were similar between CON and ECC in all groups. However, pennation angle increases were greater in CON, and fascicle length changes were greater in ECC. Notably, muscle and tendon adaptations appeared to occur in synergy, presumably to maintain the efficacy of the muscle-tendon unit.
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Affiliation(s)
- Jonathan Iain Quinlan
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.,National Institute for Health Research, Birmingham Biomedical Research Centre At University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.,MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Martino Vladimiro Franchi
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK.,Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Nima Gharahdaghi
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Francesca Badiali
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Susan Francis
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Andrew Hale
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Bethan Eileen Phillips
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Nathaniel Szewczyk
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK.,Ohio Musculoskeletal and Neurological Institute (OMNI) and Department of Biomedical Sciences, Ohio University, Athens, OH, 43147, USA
| | - Paul Leonard Greenhaff
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Kenneth Smith
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | | | - Phillip James Atherton
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK
| | - Marco Vincenzo Narici
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research and NIHR Nottingham Biomedical Research Centre, University of Nottingham's Royal Derby Hospital Centre, Nottingham, UK. .,Department of Biomedical Sciences, University of Padova, Padova, Italy. .,CIR-MYO Myology Center, University of Padova, Padova, Italy.
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17
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Jakobsen JR, Schjerling P, Svensson RB, Buhl R, Carstensen H, Koch M, Krogsgaard MR, Kjær M, Mackey AL. RNA sequencing and immunofluorescence of the myotendinous junction of mature horses and humans. Am J Physiol Cell Physiol 2021; 321:C453-C470. [PMID: 34260300 DOI: 10.1152/ajpcell.00218.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The myotendinous junction (MTJ) is a specialized interface for transmitting high forces between the muscle and tendon and yet the MTJ is a common site of strain injury with a high recurrence rate. The aim of this study was to identify previously unknown MTJ components in mature animals and humans. Samples were obtained from the superficial digital flexor (SDF) muscle-tendon interface of 20 horses, and the tissue was separated through a sequential cryosectioning approach into muscle, MTJ (muscle tissue enriched in myofiber tips attached to the tendon), and tendon fractions. RT-PCR was performed for genes known to be expressed in the three tissue fractions and t-distributed stochastic neighbor embedding (t-SNE) plots were used to select the muscle, MTJ, and tendon samples from five horses for RNA sequencing. The expression of previously known and unknown genes identified through RNA sequencing was studied by immunofluorescence on human hamstring MTJ tissue. The main finding was that RNA sequencing identified the expression of a panel of 61 genes enriched at the MTJ. Of these, 48 genes were novel for the MTJ and 13 genes had been reported to be associated with the MTJ in earlier studies. The expression of known [COL22A1 (collagen XXII), NCAM (neural cell adhesion molecule), POSTN (periostin), NES (nestin), OSTN (musclin/osteocrin)] and previously undescribed [MNS1 (meiosis-specific nuclear structural protein 1), and LCT (lactase)] MTJ genes was confirmed at the protein level by immunofluorescence on tissue sections of human MTJ. In conclusion, in muscle-tendon interface tissue enriched with myofiber tips, we identified the expression of previously unknown MTJ genes representing diverse biological processes, which may be important in the maintenance of the specialized MTJ.
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Affiliation(s)
- Jens R Jakobsen
- Section for Sports Traumatology M51, Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Rene B Svensson
- Institute of Sports Medicine Copenhagen, Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Rikke Buhl
- Department of Veterinary Clinical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Helena Carstensen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Manuel Koch
- Institute for Dental Research and Oral Musculoskeletal Biology, Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.,Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Michael R Krogsgaard
- Section for Sports Traumatology M51, Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark
| | - Michael Kjær
- Institute of Sports Medicine Copenhagen, Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopaedic Surgery, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark.,Xlab, Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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18
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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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19
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Monti E, Reggiani C, Franchi MV, Toniolo L, Sandri M, Armani A, Zampieri S, Giacomello E, Sarto F, Sirago G, Murgia M, Nogara L, Marcucci L, Ciciliot S, Šimunic B, Pišot R, Narici MV. Neuromuscular junction instability and altered intracellular calcium handling as early determinants of force loss during unloading in humans. J Physiol 2021; 599:3037-3061. [PMID: 33881176 PMCID: PMC8359852 DOI: 10.1113/jp281365] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/30/2021] [Indexed: 01/18/2023] Open
Abstract
Key points Few days of unloading are sufficient to induce a decline of skeletal muscle mass and function; notably, contractile force is lost at a faster rate than muscle mass. The reasons behind this disproportionate loss of muscle force are still poorly understood. We provide strong evidence of two mechanisms only hypothesized until now for the rapid muscle force loss in only 10 days of bed rest. Our results show that an initial neuromuscular junction instability, accompanied by alterations in the innervation status and impairment of single fibre sarcoplasmic reticulum function contribute to the loss of contractile force in front of a preserved myofibrillar function and central activation capacity. Early onset of neuromuscular junction instability and impairment in calcium dynamics involved in excitation–contraction coupling are proposed as eligible determinants to the greater decline in muscle force than in muscle size during unloading.
Abstract Unloading induces rapid skeletal muscle atrophy and functional decline. Importantly, force is lost at a much higher rate than muscle mass. We aimed to investigate the early determinants of the disproportionate loss of force compared to that of muscle mass in response to unloading. Ten young participants underwent 10 days of bed rest (BR). At baseline (BR0) and at 10 days (BR10), quadriceps femoris (QF) volume (VOL) and isometric maximum voluntary contraction (MVC) were assessed. At BR0 and BR10 blood samples and biopsies of vastus lateralis (VL) muscle were collected. Neuromuscular junction (NMJ) stability and myofibre innervation status were assessed, together with single fibre mechanical properties and sarcoplasmic reticulum (SR) calcium handling. From BR0 to BR10, QFVOL and MVC decreased by 5.2% (P = 0.003) and 14.3% (P < 0.001), respectively. Initial and partial denervation was detected from increased neural cell adhesion molecule (NCAM)‐positive myofibres at BR10 compared with BR0 (+3.4%, P = 0.016). NMJ instability was further inferred from increased C‐terminal agrin fragment concentration in serum (+19.2% at BR10, P = 0.031). Fast fibre cross‐sectional area (CSA) showed a trend to decrease by 15% (P = 0.055) at BR10, while single fibre maximal tension (force/CSA) was unchanged. However, at BR10 SR Ca2+ release in response to caffeine decreased by 35.1% (P < 0.002) and 30.2% (P < 0.001) in fast and slow fibres, respectively, pointing to an impaired excitation–contraction coupling. These findings support the view that the early onset of NMJ instability and impairment in SR function are eligible mechanisms contributing to the greater decline in muscle force than in muscle size during unloading. Few days of unloading are sufficient to induce a decline of skeletal muscle mass and function; notably, contractile force is lost at a faster rate than muscle mass. The reasons behind this disproportionate loss of muscle force are still poorly understood. We provide strong evidence of two mechanisms only hypothesized until now for the rapid muscle force loss in only 10 days of bed rest. Our results show that an initial neuromuscular junction instability, accompanied by alterations in the innervation status and impairment of single fibre sarcoplasmic reticulum function contribute to the loss of contractile force in front of a preserved myofibrillar function and central activation capacity. Early onset of neuromuscular junction instability and impairment in calcium dynamics involved in excitation–contraction coupling are proposed as eligible determinants to the greater decline in muscle force than in muscle size during unloading.
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Affiliation(s)
- Elena Monti
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Science and Research Center Koper, Institute for Kinesiology Research, Koper, 6000, Slovenia
| | - Martino V Franchi
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Luana Toniolo
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Marco Sandri
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Department of Biomedical Sciences, Venetian Institute of Molecular Medicine, University of Padova, Via Orus 2, Padova, 35129, Italy
| | - Andrea Armani
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Department of Biomedical Sciences, Venetian Institute of Molecular Medicine, University of Padova, Via Orus 2, Padova, 35129, Italy
| | - Sandra Zampieri
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Department of Surgery, Oncology, and Gastroenterology, University of Padova, Padova, 35124, Italy
| | - Emiliana Giacomello
- Clinical Department of Medical, Surgical and Health Sciences, Strada di Fiume, 447, Trieste, 34149, Italy
| | - Fabio Sarto
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Giuseppe Sirago
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Marta Murgia
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry Am Klopferspitz 18, Martinsried, 82152, Germany
| | - Leonardo Nogara
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Lorenzo Marcucci
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy
| | - Stefano Ciciliot
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Department of Biomedical Sciences, Venetian Institute of Molecular Medicine, University of Padova, Via Orus 2, Padova, 35129, Italy
| | - Boštjan Šimunic
- Science and Research Center Koper, Institute for Kinesiology Research, Koper, 6000, Slovenia
| | - Rado Pišot
- Science and Research Center Koper, Institute for Kinesiology Research, Koper, 6000, Slovenia
| | - Marco V Narici
- Department of Biomedical Sciences, University of Padova, Padova, 35131, Italy.,Science and Research Center Koper, Institute for Kinesiology Research, Koper, 6000, Slovenia.,CIR-MYO Myology Center, University of Padova, Padova, 35131, Italy
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20
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Solovyeva EM, Ibebunjo C, Utzinger S, Eash JK, Dunbar A, Naumann U, Zhang Y, Serluca FC, Demirci S, Oberhauser B, Black F, Rausch M, Hoersch S, Meyer AS. New insights into molecular changes in skeletal muscle aging and disease: Differential alternative splicing and senescence. Mech Ageing Dev 2021; 197:111510. [PMID: 34019916 DOI: 10.1016/j.mad.2021.111510] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 05/09/2021] [Accepted: 05/17/2021] [Indexed: 02/08/2023]
Abstract
Progressive loss of muscle mass and function due to muscle fiber atrophy and loss in the elderly and chronically ill is now defined as sarcopenia. It is a major contributor to loss of independence, disability, need of long-term care as well as overall mortality. Sarcopenia is a heterogenous disease and underlying mechanisms are not completely understood. Here, we newly identified and used Tmem158, alongside Cdkn1a, as relevant senescence and denervation markers (SDMs), associated with muscle fiber atrophy. Subsequent application of laser capture microdissection (LCM) and RNA analyses revealed age- and disease-associated differences in gene expression and alternative splicing patterns in a rodent sarcopenia model. Of note, genes exhibiting such differential alternative splicing (DAS) are mainly involved in the contractile function of the muscle. Many of these splicing events are also found in a mouse model for myotonic dystrophy type 1 (DM1), underscoring the premature aging phenotype of this disease. We propose to add differential alternative splicing to the hallmarks of aging.
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Affiliation(s)
- Elizaveta M Solovyeva
- NIBR Informatics, 4056, Basel, Switzerland; V.L. Talrose Institute for Energy Problems of Chemical Physics, N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, Moscow, 119334, Russia; Moscow Institute of Physics and Technology (State University), Dolgoprudny, Moscow Region, 141701, Russia
| | | | - Stephan Utzinger
- Novartis Institute for Biomedical Research (NIBR), Musculoskeletal Diseases, 4056, Basel, Switzerland
| | - John K Eash
- NIBR, Musculoskeletal Diseases, Cambridge, MA, 02139, USA
| | - Andrew Dunbar
- NIBR, Analytical Sciences and Imaging, 4056, Basel, Switzerland
| | - Ulrike Naumann
- NIBR, Chemical Biology & Therapeutics, 4056, Basel, Switzerland
| | - Yunyu Zhang
- NIBR, Musculoskeletal Diseases, Cambridge, MA, 02139, USA
| | | | - Sabrina Demirci
- Novartis Institute for Biomedical Research (NIBR), Musculoskeletal Diseases, 4056, Basel, Switzerland
| | | | - Frederique Black
- NIBR, Cardiovascular & Metabolic Diseases, Cambridge, MA02139, USA
| | - Martin Rausch
- NIBR, Analytical Sciences and Imaging, 4056, Basel, Switzerland
| | | | - Angelika S Meyer
- Novartis Institute for Biomedical Research (NIBR), Musculoskeletal Diseases, 4056, Basel, Switzerland.
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21
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Graham ZA, Lavin KM, O'Bryan SM, Thalacker-Mercer AE, Buford TW, Ford KM, Broderick TJ, Bamman MM. Mechanisms of exercise as a preventative measure to muscle wasting. Am J Physiol Cell Physiol 2021; 321:C40-C57. [PMID: 33950699 DOI: 10.1152/ajpcell.00056.2021] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Skeletal muscle is the most abundant tissue in healthy individuals and it has important roles in health beyond voluntary movement. The overall mass and energy requirements of skeletal muscle require it to be metabolically active and flexible to multiple energy substrates. The tissue has evolved to be largely load dependent and it readily adapts in a number of positive ways to repetitive overload, such as various forms of exercise training. However, unloading from extended bed rest and/or metabolic derangements in response to trauma, acute illness, or severe pathology, commonly results in rapid muscle wasting. Decline in muscle mass contributes to multimorbidity, reduces function, and exerts a substantial, negative impact on the quality of life. The principal mechanisms controlling muscle mass have been well described and these cellular processes are intricately regulated by exercise. Accordingly, exercise has shown great promise and efficacy in preventing or slowing muscle wasting through changes in molecular physiology, organelle function, cell signaling pathways, and epigenetic regulation. In this review, we focus on the role of exercise in altering the molecular landscape of skeletal muscle in a manner that improves or maintains its health and function in the presence of unloading or disease.epigenetics; exercise; muscle wasting; resistance training; skeletal muscle.
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Affiliation(s)
- Zachary A Graham
- Birmingham VA Medical Center, Birmingham, Alabama.,Florida Institute for Human and Machine Cognition, Pensacola, Florida.,Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama.,UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Kaleen M Lavin
- Florida Institute for Human and Machine Cognition, Pensacola, Florida.,Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama.,UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Samia M O'Bryan
- Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama.,UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Anna E Thalacker-Mercer
- Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama.,UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Thomas W Buford
- UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama.,Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama.,Nathan Shock Center, The University of Alabama at Birmingham, Birmingham, Alabama
| | - Kenneth M Ford
- Florida Institute for Human and Machine Cognition, Pensacola, Florida
| | | | - Marcas M Bamman
- Florida Institute for Human and Machine Cognition, Pensacola, Florida.,Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama.,UAB Center for Exercise Medicine, The University of Alabama at Birmingham, Birmingham, Alabama.,Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama
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22
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Abstract
PURPOSE OF REVIEW This review encompasses the main novelties regarding nonimmune mechanisms implicated in the pathogenesis of idiopathic inflammatory myopathies (IIM). RECENT FINDINGS In recent years, growing data support a role for endoplasmic-reticulum (ER) stress as a propagator of muscular damage, together with the release of interferon type I and reactive oxygen species in hypoxemic muscle fibers. Other studies evaluating the relationship between autophagy and Toll-like receptors (TLRs) in IIM subtypes have shown increased TLR3 and TLR4 expression in fibers of IIM patients and colocalization with LC3, an autophagy marker, submitting autophagy as a likely player in IIM pathogenesis. Most novel evidences concern the potential role of denervation of the neuromuscular junction in IIM, possibly connected to hyperexpression of MHC-I, and trafficking of extracellular vesicles, which may represent a connection between nonimmune and immune-mediated mechanisms of muscle inflammation and damage. SUMMARY Nonimmune mechanisms contribute to the pathogenesis of IIM, likely cooperating with immune-mediated inflammation. Consistent data were released for ER stress, autophagy, mitochondrial dysfunction and hypoxia; in addition to, neuromuscular denervation and extracellular vesicles have been proposed as thoughtful links between muscle inflammation, damage and atrophy. Further understanding of nonimmune abnormalities and potential reversible pathways is needed to improve the management of IIM.
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23
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Sewry CA, Feng L, Chambers D, Matthews E, Phadke R. Importance of immunohistochemical evaluation of developmentally regulated myosin heavy chains in human muscle biopsies. Neuromuscul Disord 2021; 31:371-384. [PMID: 33685841 DOI: 10.1016/j.nmd.2021.02.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/13/2021] [Accepted: 02/09/2021] [Indexed: 01/01/2023]
Abstract
Our retrospective immunohistochemical study of normal quadriceps muscle biopsies shows that embryonic myosin heavy chains are down-regulated by, or soon after, birth. Fetal myosin heavy chains are down-regulated by 4-6 months. Thus the presence of an appreciable number of fibres with embryonic myosin heavy chains at birth or of fetal myosin heavy chains after 6 months of age suggests a delay in maturation or an underlying abnormality. Regenerating fibres in dystrophic muscle often co-express both embryonic and fetal myosin heavy chains but more fibres with fetal than embryonic myosin heavy chains can occur. Embryonic myosin heavy chains are a useful marker of regeneration but effects of denervation, stress, disuse, and fibre maintenance also have to be taken into account. In neurogenic disorders fibres with embryonic myosin heavy chains are rare but fetal myosin heavy chain expression is common, particularly in 5q spinal muscle atrophy. Nuclear clumps in denervated muscle show fetal and sometimes embryonic myosin heavy chains. Developmentally regulated myosins are useful for highlighting the perifascicular atrophy in juvenile dermatomyositis. Our studies highlight the importance of baseline data for embryonic and fetal myosin heavy chains in human muscle biopsies and the importance of assessing them in a spectrum of neuromuscular disorders.
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Affiliation(s)
- C A Sewry
- The Dubowitz Neuromuscular Centre, UCL Queen Square Institute of Neurology Division of Neuropathology & National Hospital for Neurology and Neurosurgery, London WC1N 3BG, United Kingdom; Department of Musculoskeletal Histopathology and the Wolfson Centre for Inherited Neuromuscular Diseases, RJAH Orthopaedic Hospital NHS Trust, Oswestry, SY10 7AG, United Kingdom; Department of Cellular Pathology, Salford Royal Hospital NHS Foundation Trust, Northern Care Alliance NHS Group, Stott Lane, Salford M6 8HD, United Kingdom; The Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, United Kingdom.
| | - L Feng
- The Dubowitz Neuromuscular Centre, UCL Queen Square Institute of Neurology Division of Neuropathology & National Hospital for Neurology and Neurosurgery, London WC1N 3BG, United Kingdom; The Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, United Kingdom
| | - D Chambers
- The Dubowitz Neuromuscular Centre, UCL Queen Square Institute of Neurology Division of Neuropathology & National Hospital for Neurology and Neurosurgery, London WC1N 3BG, United Kingdom; The Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, United Kingdom; The Dubowitz Neuromuscular Centre, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health 30 Guildford Street, London, WC1N 1EH, United Kingdom
| | - E Matthews
- Atkinson-Morley Neuromuscular Centre, Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, SW17 0QT, United Kingdom; Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London WC1N 3BG, United Kingdom
| | - R Phadke
- The Dubowitz Neuromuscular Centre, UCL Queen Square Institute of Neurology Division of Neuropathology & National Hospital for Neurology and Neurosurgery, London WC1N 3BG, United Kingdom; The Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, United Kingdom; Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 3BG, United Kingdom
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24
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Bao Z, Cui C, Chow SKH, Qin L, Wong RMY, Cheung WH. AChRs Degeneration at NMJ in Aging-Associated Sarcopenia-A Systematic Review. Front Aging Neurosci 2020; 12:597811. [PMID: 33362532 PMCID: PMC7759742 DOI: 10.3389/fnagi.2020.597811] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 11/19/2020] [Indexed: 12/16/2022] Open
Abstract
Sarcopenia is an aging process with a decline of skeletal muscle mass and function, which is a challenging public health problem with reduced quality of life in patients. The endplate, the post-synaptic part of the neuromuscular junction (NMJ), occupies 0.1% of the myofiber surface area only, but is composed of millions of acetylcholine receptors (AChRs) that are efficient in binding to acetylcholine (ACh) and triggering skeletal muscle contraction. This systematic review aims to examine aging-associated alterations of post-synaptic AChRs, including morphology, function and related gene expression. A systematic literature search was conducted in PubMed, Embase and Web of Science with relevant keywords by two independent reviewers. Original pre-clinical and clinical studies regarding AChRs changes during aging with available full text and written in English were included. Information was extracted from the included studies for further review. In total, 30 articles were included. Various parameters assessing AChRs alterations by radioassay, immunofluorescence, electrophysiology and mechanical test were reported. Endplate fragmentation and denervation were common in old skeletal muscles during aging. To ensure efficient NMJ transmission and force generation, type I or IIb muscle fibers tended to have increased ACh quanta releasing after electrical stimulations, while type IIa muscle fibers tended to have stronger binding between ACh and AChRs, but the overall function of AChRs was reduced during aging. Alterations of AChRs area depended on muscle type, species and the progress of muscle atrophy and type I muscles fibers tended to demonstrate enlarging AChRs areas. Myogenic regulator factors (MRFs) can regulate the expression of AChRs subunits, while decreased MRF4 may lead to expression changes of AChRs subunits during aging. Sarcoglycan-α can delay low-density lipoprotein receptor-related protein 4 (LRP4) degradation. This protein was increased in old muscles but still cannot suppress the degradation of LRP4. Investigating the role of these AChRs-related genes in the process of aging may provide a potential target to treat sarcopenia.
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Affiliation(s)
- Zhengyuan Bao
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Can Cui
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Simon Kwoon-Ho Chow
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Ling Qin
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Ronald Man Yeung Wong
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Wing-Hoi Cheung
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
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25
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Shirakawa T, Miyawaki A, Matsubara T, Okumura N, Okamoto H, Nakai N, Rojasawasthien T, Morikawa K, Inoue A, Goto A, Washio A, Tsujisawa T, Kawamoto T, Kokabu S. Daily Oral Administration of Protease-Treated Royal Jelly Protects Against Denervation-Induced Skeletal Muscle Atrophy. Nutrients 2020; 12:E3089. [PMID: 33050588 PMCID: PMC7600733 DOI: 10.3390/nu12103089] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 10/07/2020] [Accepted: 10/07/2020] [Indexed: 12/13/2022] Open
Abstract
Honeybees produce royal jelly (RJ) from their cephalic glands. Royal jelly is a source of nutrition for the queen honey bee throughout its lifespan and is also involved in fertility and longevity. Royal jelly has long been considered beneficial to human health. We recently observed that RJ delayed impairment of motor function during aging, affecting muscle fiber size. However, how RJ affects skeletal muscle metabolism and the functional component of RJ is as of yet unidentified. We demonstrate that feeding mice with RJ daily prevents a decrease in myofiber size following denervation without affecting total muscle weight. RJ did not affect atrophy-related genes but stimulated the expression of myogenesis-related genes, including IGF-1 and IGF receptor. Trans-10-hydroxy-2-decenoic acid (10H2DA) and 10-hydroxydecanoic acid (10HDAA), two major fatty acids contained in RJ. After ingestion, 10H2DA and 10HDAA are metabolized into 2-decenedioic acid (2DA) and sebacic acid (SA) respectively. We found that 10H2DA, 10HDAA, 2DA, and SA all regulated myogenesis of C2C12 cells, murine myoblast cells. These novel findings may be useful for potential preventative and therapeutic applications for muscle atrophy disease included in Sarcopenia, an age-related decline in skeletal muscle mass and strength.
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Affiliation(s)
- Tomohiko Shirakawa
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
- Division of Orofacial Functions and Orthodontics, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan;
| | - Aki Miyawaki
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
| | - Takuma Matsubara
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
| | - Nobuaki Okumura
- Institute for Bee Products and Health Science, Yamada Bee Company, Inc., Tomata, Okayama 708-0393, Japan; (N.O.); (H.O.)
| | - Hideto Okamoto
- Institute for Bee Products and Health Science, Yamada Bee Company, Inc., Tomata, Okayama 708-0393, Japan; (N.O.); (H.O.)
| | - Naoya Nakai
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
| | - Thira Rojasawasthien
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
| | - Kazumasa Morikawa
- Division of Pediatric and Special Care Dentistry, Department of Developmental Oral Health Science, School of Dentistry, Iwate Medical University, Shiwa, Iwate 028-3694, Japan;
| | - Asako Inoue
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
| | - Akino Goto
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
| | - Ayako Washio
- Division of Endodontics and Restorative Dentistry, Department of Oral Functions, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan;
| | - Toshiyuki Tsujisawa
- School of Oral Health Sciences, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan;
| | - Tatsuo Kawamoto
- Division of Orofacial Functions and Orthodontics, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan;
| | - Shoichiro Kokabu
- Division of Molecular Signaling and Biochemistry, Department of Health Improvement, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan; (T.S.); (A.M.); (T.M.); (N.N.); (T.R.); (A.I.); (A.G.)
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26
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Portaro S, Biasini F, Bramanti P, Naro A, Calabrò RS. Chronic inflammatory demyelinating polyradiculoneuropathy relapse after mexiletine withdrawal in a patient with concomitant myotonia congenita: A case report on a potential treatment option. Medicine (Baltimore) 2020; 99:e21117. [PMID: 32664137 PMCID: PMC7360317 DOI: 10.1097/md.0000000000021117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
INTRODUCTION we report on the first case of a woman affected by chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and recessive myotonia congenita (MC), treated with mexiletine. We aimed at describing the possible role of mexiletine in CIDP management. PATIENT CONCERNS A 44-year-old female affected by CIDP and MC, gained beneficial effects for CIDP symptoms (muscle weakness, cramps, and fatigue) and relapses, after mexiletine intake (200 mg twice a day). The patient presented with detrimental effects after mexiletine drop out, with a worsening of CIDP symptoms. INTERVENTIONS The patient reported a nearly complete remission of muscle stiffness and weakness up to 3 years since mexiletine intake. Then, she developed an allergic reaction with glottis edema, maybe related to mexiletine intake, as per emergency room doctors' evaluation, who suggested withdrawing the drug. OUTCOMES The patient significantly worsened after the medication drop out concerning both CIDP and MC symptoms. CONCLUSION This is the first report on the association of CIDP and MC in the same patient. Such diseases may share some clinical symptoms related to a persistent sodium currents increase, which maybe due either to the over-expression of sodium channels following axonal damage due to demyelination or to the chloride channel genes mutations. This is the possible reason why mexiletine maybe promising to treat CIDP symptoms.
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27
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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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28
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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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