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Pajski ML, Maroto R, Byrd C, Graber TG. Longitudinal Decline of Exercise Capacity in Male and Female Mice. J Gerontol A Biol Sci Med Sci 2025; 80:glae293. [PMID: 39693388 PMCID: PMC11809237 DOI: 10.1093/gerona/glae293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Indexed: 12/20/2024] Open
Abstract
The population of older adults is exponentially expanding. Alongside aging comes the onset of chronic disease, decline of functional capacity, and reduced quality of life. Thus, this population increase will stress the capacity and financial viability of health and long-term care systems. Developing preclinical models for age-related functional decline is imperative to advancing therapies that extend healthspan and prolong independence. Previously in a cross-sectional study, we established a powerful composite scoring system we termed CFAB (Comprehensive Functional Assessment Battery). CFAB measures physical function and exercise capacity using well-validated determinants to measure overall motor function, fore-limb strength, four-limb strength/endurance, aerobic capacity, and volitional exercise/activity rate. In the current work, we used CFAB to track cohorts of male and female C57BL/6 mice over the lifespan (measuring CFAB at 6, 12, 18, 24, and 28 months of age). Overall, we found statistically significantly declining function as the mice aged, with some differences between males and females in trajectory and slope. We also determined that body mass changes presented differently between sexes, and tracked body composition (fat percentage, using magnetic resonance imagery) in females. In a subset of mice, we tracked in vivo contractile physiology noting declines in plantar flexor maximum isometric torque. In summary, our data suggest that males and females declined at different rates. We confirmed the efficacy of CFAB to track longitudinal changes in exercise capacity and physical fitness in both males and females, further validating the system to track age-related functional decline.
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Affiliation(s)
- Megan L Pajski
- Department of Physical Therapy, East Carolina University (ECU), Greenville, North Carolina, USA
| | - Rosario Maroto
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Chris Byrd
- Department of Physical Therapy, East Carolina University (ECU), Greenville, North Carolina, USA
| | - Ted G Graber
- Department of Physical Therapy, East Carolina University (ECU), Greenville, North Carolina, USA
- Department of Physiology, East Carolina University (ECU), Greenville, North Carolina, USA
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2
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Fessard A, Zavoriti A, Boyer N, Guillemaud J, Rahmati M, Del Carmine P, Gobet C, Chazaud B, Gondin J. Neuromuscular electrical stimulation training induces myonuclear accretion and hypertrophy in mice without overt signs of muscle damage and regeneration. Skelet Muscle 2025; 15:3. [PMID: 39910613 DOI: 10.1186/s13395-024-00372-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 12/23/2024] [Indexed: 02/07/2025] Open
Abstract
BACKGROUND Skeletal muscle is a plastic tissue that adapts to increased mechanical loading/contractile activity through fusion of muscle stem cells (MuSCs) with myofibers, a physiological process referred to as myonuclear accretion. However, it is still unclear whether myonuclear accretion is driven by increased mechanical loading per se, or occurs, at least in part, in response to muscle injury/regeneration. Here, we developed a non-damaging protocol to evaluate contractile activity-induced myonuclear accretion/hypertrophy in physiological conditions. METHODS Contractile activity was generated by applying repeated electrical stimuli over the mouse plantar flexor muscles. This method is commonly referred to as NeuroMuscular Electrical Simulation (NMES) in Human. Each NMES training session consisted of 80 isometric contractions delivered at ∼15% of maximal tetanic force to avoid muscle damage. C57BL/6J male mice were submitted to either a short (i.e., 6 sessions) or long (i.e., 12 sessions) individualized NMES training program while unstimulated mice were used as controls. Histological investigations were performed to assess the impact of NMES on MuSC number and status, myonuclei content and muscle tissue integrity, typology and size. RESULTS NMES led to a robust proliferation of MuSCs and myonuclear accretion in the absence of overt signs of muscle damage/regeneration. NMES-induced myonuclear accretion was specific to type IIB myofibers and was an early event preceding muscle hypertrophy inasmuch as a mild increase in myofiber cross-sectional area was only observed in response to the long-term NMES training protocol. CONCLUSION We conclude that NMES-induced myonuclear accretion and muscle hypertrophy are driven by a mild increase in mechanical loading in the absence of overt signs of muscle injury.
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Affiliation(s)
- Aurélie Fessard
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Aliki Zavoriti
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Natacha Boyer
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Jules Guillemaud
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Masoud Rahmati
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
- Department of Exercise Physiology, Faculty of Literature and Human Sciences, Lorestan University, Khoramabad, Iran
| | - Peggy Del Carmine
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Christelle Gobet
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Bénédicte Chazaud
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France
| | - Julien Gondin
- Institut NeuroMyoGène (INMG), Unité Physiopathologie et Génétique du Neurone et du Muscle, Université Claude Bernard Lyon 1, CNRS UMR 5261, Inserm U1315, 8 Avenue Rockefeller, Lyon, France.
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Lecce E, Bellini A, Greco G, Martire F, Scotto di Palumbo A, Sacchetti M, Bazzucchi I. Physiological mechanisms of neuromuscular impairment in diabetes-related complications: Can physical exercise help prevent it? J Physiol 2025. [PMID: 39898972 DOI: 10.1113/jp287589] [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: 09/20/2024] [Accepted: 01/14/2025] [Indexed: 02/04/2025] Open
Abstract
Diabetes mellitus is a chronic disorder that progressively induces complications, compromising daily independence. Among these, diabetic neuropathy is particularly prevalent and contributes to substantial neuromuscular impairments in both types 1 and 2 diabetes. This condition leads to structural damage affecting both the central and peripheral nervous systems, resulting in a significant decline in sensorimotor functions. Alongside neuropathy, diabetic myopathy also contributes to muscle impairment and reduced motor performance, intensifying the neuromuscular decline. Diabetic neuropathy typically implicates neurogenic muscle atrophy, motoneuron loss and clustering of muscle fibres as a result of aberrant denervation-reinervation processes. These complications are associated with compromised neuromuscular junctions, where alterations occur in pre-synaptic vesicles, mitochondrial content and post-synaptic signalling. Neural damage is intensified by chronic hyperglycaemia and oxidative stress, exacerbating vascular dysfunction and reducing oxygen delivery. These complications imply a severe decline in neuromuscular performance, evidenced by reductions in maximal force and power output, rate of force development and muscle endurance. Furthermore, diabetes-related complications are compounded by age-related degenerative changes in long-term patients. Aerobic and resistance training offer promising approaches for managing blood glucose levels and neuromuscular function. Aerobic exercise promotes mitochondrial biogenesis and angiogenesis, supporting metabolic and cardiovascular health. Resistance training primarily enhances neural plasticity, muscle strength and hypertrophy, which are crucial factors for mitigating sarcopenia and preserving functional independence. This topical review examines current evidence on the physiological mechanisms underlying diabetic neuropathy and the potential impact of physical activity in counteracting this decline.
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Affiliation(s)
- Edoardo Lecce
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
| | - Alessio Bellini
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
| | - Giuseppe Greco
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
| | - Fiorella Martire
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
| | - Alessandro Scotto di Palumbo
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
| | - Massimo Sacchetti
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
| | - Ilenia Bazzucchi
- Laboratory of Exercise Physiology, Department of Movement, Human, and Health Sciences, University of 'Foro Italico', Rome, Italy
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Chambers TL, Dimet‐Wiley A, Keeble AR, Haghani A, Lo W, Kang G, Brooke R, Horvath S, Fry CS, Watowich SJ, Wen Y, Murach KA. Methylome-proteome integration after late-life voluntary exercise training reveals regulation and target information for improved skeletal muscle health. J Physiol 2025; 603:211-237. [PMID: 39058663 PMCID: PMC11702923 DOI: 10.1113/jp286681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/02/2024] [Indexed: 07/28/2024] Open
Abstract
Exercise is a potent stimulus for combatting skeletal muscle ageing. To study the effects of exercise on muscle in a preclinical setting, we developed a combined endurance-resistance training stimulus for mice called progressive weighted wheel running (PoWeR). PoWeR improves molecular, biochemical, cellular and functional characteristics of skeletal muscle and promotes aspects of partial epigenetic reprogramming when performed late in life (22-24 months of age). In this investigation, we leveraged pan-mammalian DNA methylome arrays and tandem mass-spectrometry proteomics in skeletal muscle to provide detailed information on late-life PoWeR adaptations in female mice relative to age-matched sedentary controls (n = 7-10 per group). Differential CpG methylation at conserved promoter sites was related to transcriptional regulation genes as well as Nr4a3, Hes1 and Hox genes after PoWeR. Using a holistic method of -omics integration called binding and expression target analysis (BETA), methylome changes were associated with upregulated proteins related to global and mitochondrial translation after PoWeR (P = 0.03). Specifically, BETA implicated methylation control of ribosomal, mitoribosomal, and mitochondrial complex I protein abundance after training. DNA methylation may also influence LACTB, MIB1 and UBR4 protein induction with exercise - all are mechanistically linked to muscle health. Computational cistrome analysis predicted several transcription factors including MYC as regulators of the exercise trained methylome-proteome landscape, corroborating prior late-life PoWeR transcriptome data. Correlating the proteome to muscle mass and fatigue resistance revealed positive relationships with VPS13A and NPL levels, respectively. Our findings expose differential epigenetic and proteomic adaptations associated with translational regulation after PoWeR that could influence skeletal muscle mass and function in aged mice. KEY POINTS: Late-life combined endurance-resistance exercise training from 22-24 months of age in mice is shown to improve molecular, biochemical, cellular and in vivo functional characteristics of skeletal muscle and promote aspects of partial epigenetic reprogramming and epigenetic age mitigation. Integration of DNA CpG 36k methylation arrays using conserved sites (which also contain methylation ageing clock sites) with exploratory proteomics in skeletal muscle extends our prior work and reveals coordinated and widespread regulation of ribosomal, translation initiation, mitochondrial ribosomal (mitoribosomal) and complex I proteins after combined voluntary exercise training in a sizeable cohort of female mice (n = 7-10 per group and analysis). Multi-omics integration predicted epigenetic regulation of serine β-lactamase-like protein (LACTB - linked to tumour resistance in muscle), mind bomb 1 (MIB1 - linked to satellite cell and type 2 fibre maintenance) and ubiquitin protein ligase E3 component N-recognin 4 (UBR4 - linked to muscle protein quality control) after training. Computational cistrome analysis identified MYC as a regulator of the late-life training proteome, in agreement with prior transcriptional analyses. Vacuolar protein sorting 13 homolog A (VPS13A) was positively correlated to muscle mass, and the glycoprotein/glycolipid associated sialylation enzyme N-acetylneuraminate pyruvate lyase (NPL) was associated to in vivo muscle fatigue resistance.
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Affiliation(s)
- Toby L. Chambers
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and RecreationUniversity of ArkansasFayettevilleARUSA
| | | | - Alexander R. Keeble
- University of Kentucky Center for Muscle BiologyLexingtonKYUSA
- Department of Athletic Training and Clinical NutritionUniversity of KentuckyLexingtonKYUSA
| | - Amin Haghani
- Department of Human GeneticsUniversity of California Los AngelesLos AngelesCAUSA
- Altos LabsSan DiegoCAUSA
| | - Wen‐Juo Lo
- Department of Educational Statistics and Research MethodsUniversity of ArkansasFayettevilleARUSA
| | - Gyumin Kang
- University of Kentucky Center for Muscle BiologyLexingtonKYUSA
- Department of PhysiologyUniversity of KentuckyLexingtonKYUSA
- Division of Biomedical Informatics, Department of Internal MedicineUniversity of KentuckyLexingtonKYUSA
| | - Robert Brooke
- Epigenetic Clock Development FoundationLos AngelesCAUSA
| | - Steve Horvath
- Department of Human GeneticsUniversity of California Los AngelesLos AngelesCAUSA
- Altos LabsSan DiegoCAUSA
- Epigenetic Clock Development FoundationLos AngelesCAUSA
| | - Christopher S. Fry
- University of Kentucky Center for Muscle BiologyLexingtonKYUSA
- Department of Athletic Training and Clinical NutritionUniversity of KentuckyLexingtonKYUSA
| | - Stanley J. Watowich
- Ridgeline TherapeuticsHoustonTXUSA
- Department of Biochemistry and Molecular BiologyUniversity of Texas Medical BranchGalvestonTXUSA
| | - Yuan Wen
- University of Kentucky Center for Muscle BiologyLexingtonKYUSA
- Department of PhysiologyUniversity of KentuckyLexingtonKYUSA
- Division of Biomedical Informatics, Department of Internal MedicineUniversity of KentuckyLexingtonKYUSA
| | - Kevin A. Murach
- Exercise Science Research Center, Molecular Muscle Mass Regulation Laboratory, Department of Health, Human Performance, and RecreationUniversity of ArkansasFayettevilleARUSA
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5
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Matta L, Blaas L, Gibis C, Guerra J. Functions require junctions: endurance exercise protects from age-induced alterations of the neuromuscular system. J Physiol 2025; 603:37-39. [PMID: 38530283 DOI: 10.1113/jp286232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 03/12/2024] [Indexed: 03/27/2024] Open
Affiliation(s)
- Leonardo Matta
- Institute for Cardiovascular Prevention (IPEK), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
- Institute for Diabetes and Cancer (IDC), Helmholtz Centre Munich, German Research Centre for Environmental Health, Neuherberg, Germany
| | - Lukas Blaas
- Institute for Cardiovascular Prevention (IPEK), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Christoph Gibis
- Institute for Cardiovascular Prevention (IPEK), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Joel Guerra
- Institute for Cardiovascular Prevention (IPEK), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
- Institute for Diabetes and Cancer (IDC), Helmholtz Centre Munich, German Research Centre for Environmental Health, Neuherberg, Germany
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6
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Sundberg CW. Physiology of ageing skeletal muscle and the protective effects of exercise. J Physiol 2025; 603:3-6. [PMID: 39742435 DOI: 10.1113/jp287926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2024] [Accepted: 12/17/2024] [Indexed: 01/03/2025] Open
Affiliation(s)
- Christopher W Sundberg
- Exercise Science Program, Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin, USA
- Athletic and Human Performance Research Center, Marquette University, Milwaukee, Wisconsin, USA
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7
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Lessard LER, Girard E, Streichenberger N, Petiot P, Acquaviva C, Pagan C, Mulligan P, Bouhour F, Schaeffer L, Jacquier A. Mitochondrial disorders are associated with morphological neuromuscular junction defects. Neuromuscul Disord 2024; 45:105235. [PMID: 39509867 DOI: 10.1016/j.nmd.2024.105235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2024] [Revised: 10/20/2024] [Accepted: 10/24/2024] [Indexed: 11/15/2024]
Abstract
We aimed to evaluate whether inherited mitochondrial dysfunction is associated with neuromuscular junction remodeling in patients with mitochondrial disorders. Muscle biopsies from 15 patients with mitochondrial disorders and 10 control patients were analyzed through immunostaining for various neuromuscular junction components. The patient group, with a mean age of 49.9 years, exhibited various mitochondrial disorders including chronic progressive external ophthalmoplegia, Kearns-Sayre syndrome, and mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes. Patients with mitochondrial disorders had a high percentage of remodeled (p= 0.0001), neoformed (p= 0.0049) and dilated (p= 0.016) endplates. There was a trend toward an increased proportion of neuromuscular junctions with terminal Schwann cell extension in these patients (p= 0.052). No significant difference was found in myofiber diameter between the groups. The observed neuromuscular junction defects varied widely across different mitochondrial disorder phenotypes and were present even without accompanying muscle weakness or neuropathy. This suggest that mitochondrial disorders are associated with a primary NMJ remodeling independent of muscle structural damage. Pathomechanisms underpinning this remodeling of the neuromuscular junction, as well as clinical factors predictive of this remodeling, remain to be fully characterized.
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Affiliation(s)
- Lola E R Lessard
- Service d'Electroneuromyographie et de pathologies neuromusculaires, Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, France; INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France
| | - Emmanuelle Girard
- INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France; Plateforme ANIPHY, UAR CNRS 3453, Inserm US7, Université Lyon 1, SFR Santé Lyon-Est, Lyon, France
| | - Nathalie Streichenberger
- INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France; Département d'Anatomo-Pathologie, Groupement Hospitalier Est, Hospices Civils de Lyon, Lyon, France
| | - Philippe Petiot
- Service d'Electroneuromyographie et de pathologies neuromusculaires, Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, France
| | - Cécile Acquaviva
- Service de Biochimie et Biologie Moléculaire - Unité Pathologies Héréditaires du Métabolisme, Hospices Civils De Lyon, Lyon, France
| | - Cécile Pagan
- Service de Biochimie et Biologie Moléculaire - Unité Pathologies Héréditaires du Métabolisme, Hospices Civils De Lyon, Lyon, France
| | - Peter Mulligan
- INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France
| | - Françoise Bouhour
- Service d'Electroneuromyographie et de pathologies neuromusculaires, Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, France; INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France
| | - Laurent Schaeffer
- INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France; Centre de Biotechnologie Cellulaire, Hospices Civils De Lyon, Lyon, France.
| | - Arnaud Jacquier
- INMG-PGNM, UMR CNRS 5261 - INSERM U1315, Université Lyon 1, Lyon, France; Centre de Biotechnologie Cellulaire, Hospices Civils De Lyon, Lyon, France
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8
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Tsentsevitsky AN, Sibgatullina GV, Odoshivkina YG, Khuzakhmetova VF, Tokmakova AR, Ponomareva AA, Salnikov VV, Zakirjanova GF, Petrov AM, Bukharaeva EA. Functional and Structural Changes in Diaphragm Neuromuscular Junctions in Early Aging. Int J Mol Sci 2024; 25:8959. [PMID: 39201644 PMCID: PMC11354816 DOI: 10.3390/ijms25168959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2024] [Revised: 08/10/2024] [Accepted: 08/15/2024] [Indexed: 09/02/2024] Open
Abstract
Age-related impairment of the diaphragm causes respiratory complications. Neuromuscular junction (NMJ) dysfunction can be one of the triggering events in diaphragm weaknesses in old age. Prominent structural and functional alterations in diaphragm NMJs were described in elderly rodents, but NMJ changes in middle age remain unclear. Here, we compared diaphragm muscles from young adult (3 months) and middle-aged (12 months) BALB/c mice. Microelectrode recordings, immunofluorescent staining, electron microscopy, myography, and whole-body plethysmography were used. We revealed presynaptic (i) and postsynaptic (ii) changes. The former (i) included an increase in both action potential propagation velocity and neurotransmitter release evoked by low-, moderate-, and high-frequency activity but a decrease in immunoexpression of synapsin 1 and synaptic vesicle clustering. The latter (ii) consisted of a decrease in currents via nicotinic acetylcholine receptors and the area of their distribution. These NMJ changes correlated with increased contractile responses to moderate- to high-frequency nerve activation. Additionally, we found alterations in the pattern of respiration (an increase in peak inspiratory flow and a tendency of elevation of the tidal volume), which imply increased diaphragm activity in middle-aged mice. We conclude that enhancement of neuromuscular communication (due to presynaptic mechanism) accompanied by improved contractile responses occurs in the diaphragm in early aging.
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Affiliation(s)
- Andrei N. Tsentsevitsky
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
| | - Guzel V. Sibgatullina
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
| | - Yulia G. Odoshivkina
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
- Department of Normal Physiology, Kazan State Medical University, 49 Butlerova Street, 420012 Kazan, Russia
| | - Venera F. Khuzakhmetova
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
| | - Anna R. Tokmakova
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
| | - Anastasia A. Ponomareva
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
| | - Vadim V. Salnikov
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
| | - Guzalia F. Zakirjanova
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
- Department of Normal Physiology, Kazan State Medical University, 49 Butlerova Street, 420012 Kazan, Russia
| | - Alexey M. Petrov
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
- Department of Normal Physiology, Kazan State Medical University, 49 Butlerova Street, 420012 Kazan, Russia
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 420008 Kazan, Russia
| | - Ellya A. Bukharaeva
- Kazan Institute of Biochemistry and Biophysics, Federal Research Center “Kazan Scientific Center of RAS”, 2/31 Lobachevsky Street, P.O. Box 30, 420111 Kazan, Russia; (A.N.T.); (G.V.S.); (Y.G.O.); (V.F.K.); (A.R.T.); (A.A.P.); (V.V.S.); (G.F.Z.)
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9
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Pajski ML, Maroto R, Byrd C, Graber TG. Longitudinal Decline of Exercise Capacity in Male and Female Mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.29.605646. [PMID: 39131298 PMCID: PMC11312590 DOI: 10.1101/2024.07.29.605646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
The population of older adults is exponentially expanding. Alongside aging comes the onset of chronic disease, decline of functional capacity, and reduced quality of life. Thus, this population increase will stress the capacity and financial viability of health and long-term care systems. Developing pre-clinical models for age-related functional decline is imperative to advancing therapies that extend healthspan and prolong independence. Previously in a cross-sectional study, we established a powerful composite scoring system we termed CFAB (comprehensive functional assessment battery). CFAB measures physical function and exercise capacity using well-validated determinants to measure overall motor function, fore-limb strength, four-limb strength/endurance, aerobic capacity, and volitional exercise/activity rate. In the current work, we used CFAB to track cohorts of male and female C57BL/6 mice over the lifespan (measuring CFAB at 6, 12, 18, 24, and 28 months of age). Overall, we found statistically significantly declining function as the mice aged, with some differences between males and females in trajectory and slope. We also determined that body mass changes presented differently between sexes, and tracked body composition (fat percentage, using magnetic resonance imagery) in females. In a subset of mice, we tracked in vivo contractile physiology noting declines in plantar flexor maximum isometric torque. In summary, our data suggest that males and females declined at different rates. We confirmed the efficacy of CFAB to track longitudinal changes in exercise capacity and physical fitness in both males and females, further validating the system to track age-related functional decline.
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Affiliation(s)
| | - Rosario Maroto
- University of Texas Medical Branch, Dept. of Biochemistry & Molecular Biology
| | - Chris Byrd
- East Carolina University (ECU) Dept. of Physical Therapy
| | - Ted G. Graber
- East Carolina University (ECU) Dept. of Physical Therapy
- ECU Dept. of Kinesiology
- ECU Dept. of Physiology
- East Carolina Obesity and Diabetes Institute
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