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Zhao Y, Li C, Zhou S, He Y, Wang Y, Zhang Y, Wen L. Enhanced glucose utilization of skeletal muscle after 4 weeks of intermittent hypoxia in a mouse model of type 2 diabetes. PLoS One 2024; 19:e0296815. [PMID: 38271325 PMCID: PMC10810429 DOI: 10.1371/journal.pone.0296815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 12/19/2023] [Indexed: 01/27/2024] Open
Abstract
BACKGROUND Intermittent hypoxia intervention (IHI) has been shown to reduces blood glucose and improves insulin resistance in type 2 diabetes (T2D) and has been suggested as a complementary or alternative intervention to exercise for individuals with limited mobility. Previous research on IHI has assessed cellular glucose uptake rather than utilization. The purpose of this study was to determine the effect of a 4-week IHI, with or without an aerobic exercise, on skeletal muscle glucose utilization as indicated by the changes in pyruvate, lactate, NAD+, and NADH, using a mouse model of diet-induced T2D. In addition, the effects of one exposure to hypoxia (acute) and of a 4-week IHI (chronic) were compared to explore their relationship. METHODS C57BL/6J mice were randomly assigned to normal control and high-fat-diet groups, and the mice that developed diet-induced diabetes were assigned to diabetes control, and intervention groups with 1 hour (acute) or 4 weeks (1 hour/day, 6 days/week) exposure to a hypoxic envrionment (0.15 FiO2), exercise (treadmill run) in normoxia, and exercise in hypoxia, respectively, with N = 7 in each group. The effects of the interventions on concentrations of fasting blood glucose, muscle glucose, GLUT4, lactate, pyruvate, nicotinamide adenine dinucleotide (NAD+), and NADH were measured, and statistically compared between the groups. RESULTS Compared with diabetes control group, the mice treated in the hypoxic environment for 4 weeks showed a significantly higher pyruvate levels and lower lactate/pyruvate ratios in the quadriceps muscle, and the mice exposed to hypoxia without or with aerobic exercise for either for 4 weeks or just 1 hour showed higher NAD+ levels and lower NADH/NAD+ ratios. CONCLUSIONS Exposure to moderate hypoxia for either one bout or 4 weeks significantly increased the body's mitochondrial NAD cyclethe in diabetic mice even in the absence of aerobic exercise. The hypoxia and exercise interventions exhibited synergistic effects on glycolysis. These findings provide mechanistic insights into the effects of IHI in respect of the management of hyperglycemia.
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Affiliation(s)
- Yuqi Zhao
- School of Social Sports and Health Sciences, Tianjin University of Sport, Tianjin, China
- School of Exercise and Health, Nanjing Sport Institute, Nanjing, Jiangsu, China
| | - Chaoqun Li
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Shi Zhou
- Faculty of Health, Southern Cross University, Lismore, Australia
| | - Youyu He
- School of Social Sports and Health Sciences, Tianjin University of Sport, Tianjin, China
| | - Yun Wang
- Faculty of Health, Southern Cross University, Lismore, Australia
| | - Yuan Zhang
- Faculty of Health, Southern Cross University, Lismore, Australia
| | - Li Wen
- School of Social Sports and Health Sciences, Tianjin University of Sport, Tianjin, China
- School of Exercise and Health, Nanjing Sport Institute, Nanjing, Jiangsu, China
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Aneis YM, El Refaye GE, Taha MM, Aldhahi MI, Elsisi HF. Concurrent Aerobic and Strength Training with Caloric Restriction Reduces Insulin Resistance in Obese Premenopausal Women: A Randomized Controlled Trial. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:1193. [PMID: 37512005 PMCID: PMC10384259 DOI: 10.3390/medicina59071193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 06/14/2023] [Accepted: 06/20/2023] [Indexed: 07/30/2023]
Abstract
Background and Objectives: Obese premenopausal women are at high risk of developing insulin resistance (IR). Concurrent aerobic and strength training (CAST) has been shown to provide remarkable advantages, yet its effects, along with caloric restriction in such a high-risk population, are not yet established. This study aimed to investigate the impact of concurrent aerobic and strength training with caloric restriction (CAST-CR) on IR in obese premenopausal women. Materials and Methods: Forty-two obese premenopausal women with reported IR, aged 40-50 years, were randomly allocated to either the (CAST-CR) intervention group, who underwent CAST with caloric restriction, or the (AT-CR) control group, who received aerobic training in addition to caloric restriction. Both groups completed 12 weeks of controlled training with equivalent training time. Aerobic training began at 60% and gradually progressed to achieve 75% of the maximum heart rate, while strength training was executed at 50% to 70% of the one-repetition maximum (1RM). Anthropometric measures, abdominal adiposity, metabolic parameters, and homeostasis model assessment-estimated insulin resistance (HOMA-IR) were evaluated prior to and following the intervention. Results: Both groups experienced a substantial enhancement in the selected parameters compared to the baseline (p < 0.001), with higher improvement within the CAST-CR group. The changes in HOMA-IR were -1.24 (95%CI, -1.37 to -1.12) in the CAST-CR group vs. -1.07 (95%CI, -1.19 to -0.94) in the AT-CR group. Conclusions: While AT-CR improved insulin sensitivity in premenopausal women who were obese and hyperinsulinemic, CAST with calorie restriction improved insulin sensitivity more significantly, suggesting it as a preferable alternative.
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Affiliation(s)
- Yasser M Aneis
- Department of Basic Sciences, Faculty of Physical Therapy, Cairo University, Giza 11432, Egypt
- Department of Basic Sciences, Faculty of Physical Therapy, Delta University for Science and Technology, Gamasa 11152, Egypt
| | - Ghada E El Refaye
- Department of Physical Therapy for Women's Health, Faculty of Physical Therapy, Cairo University, Giza 11432, Egypt
- Department of Physical Therapy for Women's Health, Faculty of Physical Therapy, Pharos University, Alexandria 21311, Egypt
| | - Mona Mohamed Taha
- Department of Rehabilitation Sciences, College of Health and Rehabilitation Sciences, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Monira I Aldhahi
- Department of Rehabilitation Sciences, College of Health and Rehabilitation Sciences, Princess Nourah Bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia
| | - Hany F Elsisi
- Department of Physical Therapy for Cardiovascular/Respiratory Disorders and Geriatrics, Faculty of Physical Therapy, Cairo University, Giza 11432, Egypt
- Department of Respiratory Therapy, College of Applied Medical Sciences, University of Bisha, Bisha 61922, Saudi Arabia
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Miglietta S, Cristiano L, Espinola MSB, Masiello MG, Micara G, Battaglione E, Linari A, Palmerini MG, Familiari G, Aragona C, Bizzarri M, Macchiarelli G, Nottola SA. Effects of Simulated Microgravity In Vitro on Human Metaphase II Oocytes: An Electron Microscopy-Based Study. Cells 2023; 12:1346. [PMID: 37408181 DOI: 10.3390/cells12101346] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 05/04/2023] [Accepted: 05/05/2023] [Indexed: 07/07/2023] Open
Abstract
The Gravity Force to which living beings are subjected on Earth rules the functionality of most biological processes in many tissues. It has been reported that a situation of Microgravity (such as that occurring in space) causes negative effects on living beings. Astronauts returning from space shuttle missions or from the International Space Station have been diagnosed with various health problems, such as bone demineralization, muscle atrophy, cardiovascular deconditioning, and vestibular and sensory imbalance, including impaired visual acuity, altered metabolic and nutritional status, and immune system dysregulation. Microgravity has profound effects also on reproductive functions. Female astronauts, in fact, suppress their cycles during space travels, and effects at the cellular level in the early embryo development and on female gamete maturation have also been observed. The opportunities to use space flights to study the effects of gravity variations are limited because of the high costs and lack of repeatability of the experiments. For these reasons, the use of microgravity simulators for studying, at the cellular level, the effects, such as those, obtained during/after a spatial trip, are developed to confirm that these models can be used in the study of body responses under conditions different from those found in a unitary Gravity environment (1 g). In view of this, this study aimed to investigate in vitro the effects of simulated microgravity on the ultrastructural features of human metaphase II oocytes using a Random Positioning Machine (RPM). We demonstrated for the first time, by Transmission Electron Microscopy analysis, that microgravity might compromise oocyte quality by affecting not only the localization of mitochondria and cortical granules due to a possible alteration of the cytoskeleton but also the function of mitochondria and endoplasmic reticulum since in RPM oocytes we observed a switch in the morphology of smooth endoplasmic reticulum (SER) and associated mitochondria from mitochondria-SER aggregates to mitochondria-vesicle complexes. We concluded that microgravity might negatively affect oocyte quality by interfering in vitro with the normal sequence of morphodynamic events essential for acquiring and maintaining a proper competence to fertilization in human oocytes.
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Affiliation(s)
- Selenia Miglietta
- Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00165 Rome, Italy
| | - Loredana Cristiano
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Maria Salomé B Espinola
- Systems Biology Group, Department of Experimental Medicine, Sapienza University, 00165 Rome, Italy
| | - Maria Grazia Masiello
- Systems Biology Group, Department of Experimental Medicine, Sapienza University, 00165 Rome, Italy
| | - Giulietta Micara
- Department of Maternal, Infantile and Urological Sciences, Sapienza University, 00165 Rome, Italy
| | - Ezio Battaglione
- Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00165 Rome, Italy
| | - Antonella Linari
- Department of Maternal, Infantile and Urological Sciences, Sapienza University, 00165 Rome, Italy
| | - Maria Grazia Palmerini
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Giuseppe Familiari
- Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00165 Rome, Italy
| | - Cesare Aragona
- Systems Biology Group, Department of Experimental Medicine, Sapienza University, 00165 Rome, Italy
| | - Mariano Bizzarri
- Systems Biology Group, Department of Experimental Medicine, Sapienza University, 00165 Rome, Italy
| | - Guido Macchiarelli
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Stefania A Nottola
- Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, Sapienza University, 00165 Rome, Italy
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Zhang J, Li Y. Propofol-Induced Developmental Neurotoxicity: From Mechanisms to Therapeutic Strategies. ACS Chem Neurosci 2023; 14:1017-1032. [PMID: 36854650 DOI: 10.1021/acschemneuro.2c00755] [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: 03/02/2023] Open
Abstract
Propofol is the most commonly used intravenous general anesthetic in clinical anesthesia, and it is also widely used in general anesthesia for pregnant women and infants. Some clinical and preclinical studies have found that propofol causes damage to the immature nervous system, which may lead to neurodevelopmental disorders and cognitive dysfunction in infants and children. However, its potential molecular mechanism has not been fully elucidated. Recent in vivo and in vitro studies have found that some exogenous drugs and interventions can effectively alleviate propofol-induced neurotoxicity. In this review, we focus on the relevant preclinical studies and summarize the latest findings on the potential mechanisms and therapeutic strategies of propofol-induced developmental neurotoxicity.
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Affiliation(s)
- Jing Zhang
- Department of Anesthesiology, Affiliated Hospital of Qingdao University, Qingdao 266000, China.,Department of Medicine, Qingdao University, Qingdao 266000, China
| | - Yu Li
- Department of Anesthesiology, Affiliated Hospital of Qingdao University, Qingdao 266000, China
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Yang Q, Wang Y, Zhao C, Pang S, Lu J, Chan P. α-Synuclein aggregation causes muscle atrophy through neuromuscular junction degeneration. J Cachexia Sarcopenia Muscle 2023; 14:226-242. [PMID: 36416282 PMCID: PMC9891985 DOI: 10.1002/jcsm.13123] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 09/15/2022] [Accepted: 10/12/2022] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Sarcopenia is common in patients with Parkinson's disease (PD), showing mitochondrial oxidative stress in skeletal muscle. The aggregation of α-synuclein (α-Syn) to induce oxidative stress is a key pathogenic process of PD; nevertheless, we know little about its potential role in regulating peripheral nerves and the function of the muscles they innervate. METHODS To investigate the role of α-Syn aggregation on neuromuscular system, we used the Thy1 promoter to overexpress human α-Syn transgenic mice (mThy1-hSNCA). hα-Syn expression was evaluated by western blot, and its localization was determined by confocal microscopy. The impact of α-Syn aggregation on the structure and function of skeletal muscle mitochondria and neuromuscular junctions (NMJs), as well as muscle mass and function were characterized by flow cytometry, transmission electron microscopy, Seahorse XF24 metabolic assay, and AAV9 in vivo injection. We assessed the regenerative effect of mitochondrial-targeted superoxide dismutase (Mito-TEMPO) after skeletal muscle injury in mThy1-hSNCA mice. RESULTS Overexpressed hα-Syn protein localized in motor neuron axons and NMJs in muscle and formed aggregates. α-Syn aggregation increased the number of abnormal mitochondrial in the intramuscular axons and NMJs by over 60% (P < 0.01), which inhibited the release of acetylcholine (ACh) from presynaptic vesicles in NMJs (P < 0.05). The expression of genes associated with NMJ activity, neurotransmission and regulation of reactive oxygen species (ROS) metabolic process were significantly decreased in mThy1-hSNCA mice, resulting in ROS production elevated by ~220% (P < 0.05), thereby exacerbating oxidative stress. Such process altered mitochondrial spatial relationships to sarcomeric structures, decreased Z-line spacing by 36% (P < 0.05) and increased myofibre apoptosis by ~10% (P < 0.05). Overexpression of α-Syn altered the metabolic profile of muscle satellite cells (MuSCs), including basal respiratory capacity (~170% reduction) and glycolytic capacity (~150% reduction) (P < 0.05) and decreased cell migration and fusion during muscle regeneration (~60% and ~40%, respectively) (P < 0.05). We demonstrated that Mito-TEMPO treatment could restore the oxidative stress status (the complex I/V protein and enzyme activities increased ~200% and ~150%, respectively), which caused by α-Syn aggregation, and improve the ability of muscle regeneration after injury. In addition, the NMJ receptor fragmentation and ACh secretion were also improved. CONCLUSIONS These results reveal that the α-synuclein aggregation plays an important role in regulating acetylcholine release from neuromuscular junctions and induces intramuscular mitochondrial oxidative stress, which can provide new insights into the aetiology of muscle atrophy in patients with Parkinson's disease.
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Affiliation(s)
- Qiumei Yang
- Department of Neurology, Geriatrics and Neurobiology, National Clinical Research Center of Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Yanyan Wang
- Department of Neurology, Geriatrics and Neurobiology, National Clinical Research Center of Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Chunsong Zhao
- Department of Neurology, Geriatrics and Neurobiology, National Clinical Research Center of Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Shimin Pang
- Department of Neurology, Geriatrics and Neurobiology, National Clinical Research Center of Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jing Lu
- Department of Neurology, Geriatrics and Neurobiology, National Clinical Research Center of Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Piu Chan
- Department of Neurology, Geriatrics and Neurobiology, National Clinical Research Center of Geriatric Disorders, Xuanwu Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China.,Clinical Center for Parkinson's Disease, Capital Medical University, Beijing Institute of Geriatrics, Beijing, China.,Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing Key Laboratory for Parkinson's Disease, Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, China
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Qiu Y, Fernández-García B, Lehmann HI, Li G, Kroemer G, López-Otín C, Xiao J. Exercise sustains the hallmarks of health. JOURNAL OF SPORT AND HEALTH SCIENCE 2023; 12:8-35. [PMID: 36374766 PMCID: PMC9923435 DOI: 10.1016/j.jshs.2022.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/10/2022] [Accepted: 09/02/2022] [Indexed: 05/23/2023]
Abstract
Exercise has long been known for its active role in improving physical fitness and sustaining health. Regular moderate-intensity exercise improves all aspects of human health and is widely accepted as a preventative and therapeutic strategy for various diseases. It is well-documented that exercise maintains and restores homeostasis at the organismal, tissue, cellular, and molecular levels to stimulate positive physiological adaptations that consequently protect against various pathological conditions. Here we mainly summarize how moderate-intensity exercise affects the major hallmarks of health, including the integrity of barriers, containment of local perturbations, recycling and turnover, integration of circuitries, rhythmic oscillations, homeostatic resilience, hormetic regulation, as well as repair and regeneration. Furthermore, we summarize the current understanding of the mechanisms responsible for beneficial adaptations in response to exercise. This review aimed at providing a comprehensive summary of the vital biological mechanisms through which moderate-intensity exercise maintains health and opens a window for its application in other health interventions. We hope that continuing investigation in this field will further increase our understanding of the processes involved in the positive role of moderate-intensity exercise and thus get us closer to the identification of new therapeutics that improve quality of life.
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Affiliation(s)
- Yan Qiu
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong 226011, China; Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai 200444, China
| | - Benjamin Fernández-García
- Health Research Institute of the Principality of Asturias (ISPA), Oviedo 33011, Spain; Department of Morphology and Cell Biology, Anatomy, University of Oviedo, Oviedo 33006, Spain
| | - H Immo Lehmann
- Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Guoping Li
- Cardiovascular Division of the Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Guido Kroemer
- Centre de Recherche des Cordeliers, Equipe labellisée par la Ligue contre le cancer, Université de Paris Cité, Sorbonne Université, Inserm U1138, Institut Universitaire de France, Paris 75231, France; Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, Villejuif 94805, France; Institut du Cancer Paris CARPEM, Department of Biology, Hôpital Européen Georges Pompidou, AP-HP, Paris 75015, France.
| | - Carlos López-Otín
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Instituto Universitario de Oncología, Universidad de Oviedo, Oviedo 33006, Spain; Centro de Investigación Biomédica en Red Enfermedades Cáncer (CIBERONC), Oviedo 33006, Spain.
| | - Junjie Xiao
- Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong 226011, China; Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Life Science, Shanghai University, Shanghai 200444, China.
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The Impact of Exercise Training Intensity on Physiological Adaptations and Insulin Resistance in Women with Abdominal Obesity. Healthcare (Basel) 2022; 10:healthcare10122533. [PMID: 36554057 PMCID: PMC9778339 DOI: 10.3390/healthcare10122533] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022] Open
Abstract
Abdominal obesity has emerged globally as a major public health issue due to its high prevalence and morbidity. The benefits of physical exercise among the obese population are well documented. However, the optimal exercise intensity for reducing body fat and preventing insulin resistance and metabolic disorders is still under debate. This study aimed to examine the effects of three different intensities of combined endurance and strength training programs on anthropometric variables, physiological and muscular adaptations, and insulin sensitivity. Forty-three obese young women (age 26.4 ± 4.7 years, BMI 33.1 ± 2.5 kg/m2) were randomly assigned to one of four groups: a control group (G0), a moderate-intensity training group (G50, exercising brisk walking at 50% heart rate reserve HRR), a high-intensity training group (G75, exercise jogging at 75% HRR), and an alternated-intensity training group (G50/75, exercise brisk-walking/jogging at 50−75% HRR) with additional strength training once a week for each group. Body composition, waist circumference (WC), fasting blood glucose, insulin sensitivity and resistance (Homa-IR), resting heart rate (RHR), 6-min walk distance (6MWD), 1-repetition maximum (1-RM), and time to exhaustion (TTE) at 45% and 75% maximal voluntary contraction (MVC) for both the flexor and extensor muscle groups of the knees, were recorded before and after three months of exercise training. All training groups showed significant decreases in body mass, BMI, total body fat, body fat percentage, WC, abdominal and visceral mass (p < 0.001), with a greater reduction of body mass and BMI in G75 (p < 0.05). Lean mass increased significantly only in G50/75 (p < 0.05). The insulin sensitivity and Homa-IR decreased in the three training groups (p < 0.01), with greater enhanced resistance in G50 compared to G75 and G50/75 (p < 0.05). In contrast, there were no pre-post changes in all groups for fasting blood glucose (p > 0.05). 1-RM and TTE of the knee flexor and extensor muscles were improved in the three groups (p < 0.01), with greater improvement in G50/75 for 1RM and G75 in most of the TTE parameters (p < 0.05). RHR decreased and 6MWD increased significantly in the three training groups (p < 0.01), with greater 6MWD improvement in G75 (p < 0.05). In conclusion, the three training intensities seem to generate benefits in terms of body composition, physiological and muscular adaptations, and insulin resistance. High training intensity resulted in greater improvements in body mass, BMI, and endurance and strength, whereas moderate training intensity resulted in greater improvements of insulin resistance and homo-IR. Following alternate-intensity training, greater improvements were observed in lean mass and maximal strength performance.
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Lyu P, Jiang H. RNA-Sequencing Reveals Upregulation and a Beneficial Role of Autophagy in Myoblast Differentiation and Fusion. Cells 2022; 11:cells11223549. [PMID: 36428978 PMCID: PMC9688917 DOI: 10.3390/cells11223549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/02/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022] Open
Abstract
Myoblast differentiation is a complex process whereby the mononuclear muscle precursor cells myoblasts express skeletal-muscle-specific genes and fuse with each other to form multinucleated myotubes. The objective of this study was to identify potentially novel mechanisms that mediate myoblast differentiation. We first compared transcriptomes in C2C12 myoblasts before and 6 days after induction of myogenic differentiation by RNA-seq. This analysis identified 11,046 differentially expressed genes, of which 5615 and 5431 genes were upregulated and downregulated, respectively, from before differentiation to differentiation. Functional enrichment analyses revealed that the upregulated genes were associated with skeletal muscle contraction, autophagy, and sarcomeres while the downregulated genes were associated with ribonucleoprotein complex biogenesis, mRNA processing, ribosomes, and other biological processes or cellular components. Western blot analyses showed an increased conversion of LC3-I to LC3-II protein during myoblast differentiation, further demonstrating the upregulation of autophagy during myoblast differentiation. Blocking the autophagic flux in C2C12 cells with chloroquine inhibited the expression of skeletal-muscle-specific genes and the formation of myotubes, confirming a positive role for autophagy in myoblast differentiation and fusion.
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Bioactive Components in Whole Grains for the Regulation of Skeletal Muscle Function. Foods 2022; 11:foods11182752. [PMID: 36140879 PMCID: PMC9498156 DOI: 10.3390/foods11182752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 12/03/2022] Open
Abstract
Skeletal muscle plays a primary role in metabolic health and physical performance. Conversely, skeletal muscle dysfunctions such as muscular dystrophy, atrophy and aging-related sarcopenia could lead to frailty, decreased independence and increased risk of hospitalization. Dietary intervention has become an effective approach to improving muscle health and function. Evidence shows that whole grains possess multiple health benefits compared with refined grains. Importantly, there is growing evidence demonstrating that bioactive substances derived from whole grains such as polyphenols, γ-oryzanol, β-sitosterol, betaine, octacosanol, alkylresorcinols and β-glucan could contribute to enhancing myogenesis, muscle mass and metabolic function. In this review, we discuss the potential role of whole-grain-derived bioactive components in the regulation of muscle function, emphasizing the underlying mechanisms by which these compounds regulate muscle biology. This work will contribute toward increasing awareness of nutraceutical supplementation of whole grain functional ingredients for the prevention and treatment of muscle dysfunctions.
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Dzięgielewska A, Dunislawska A. Mitochondrial Dysfunctions and Potential Molecular Markers in Sport Horses. Int J Mol Sci 2022; 23:ijms23158655. [PMID: 35955789 PMCID: PMC9369138 DOI: 10.3390/ijms23158655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 02/01/2023] Open
Abstract
Mitochondria are an essential part of most eukaryotic cells. The crucial role of these organelles is the production of metabolic energy, which is converted into ATP in oxidative phosphorylation. They are also involved in and constitute apoptosis, the site of many metabolic processes. Some of the factors that negatively affect mitochondria are stress, excessive exercise, disease, and the aging process. Exercise can cause the release of large amounts of free radicals, inflammation, injury, and stress. All of these factors can contribute to mitochondrial dysfunction, which can consistently lead to inflammatory responses, tissue damage, organ dysfunction, and a host of diseases. The functions of the mitochondria and the consequences of their disturbance can be of great importance in the breeding and use of horses. The paper reviews mitochondrial disorders in horses and, based on the literature, indicates genetic markers strongly related to this issue.
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Genome-wide identification of enhancers and transcription factors regulating the myogenic differentiation of bovine satellite cells. BMC Genomics 2021; 22:901. [PMID: 34915843 PMCID: PMC8675486 DOI: 10.1186/s12864-021-08224-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 11/29/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Satellite cells are the myogenic precursor cells in adult skeletal muscle. The objective of this study was to identify enhancers and transcription factors that regulate gene expression during the differentiation of bovine satellite cells into myotubes. RESULTS Chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) was performed to identify genomic regions where lysine 27 of H3 histone is acetylated (H3K27ac), i.e., active enhancers, from bovine satellite cells before and during differentiation into myotubes. A total of 19,027 and 47,669 H3K27ac-marked enhancers were consistently identified from two biological replicates of before- and during-differentiation bovine satellite cells, respectively. Of these enhancers, 5882 were specific to before-differentiation, 35,723 to during-differentiation, and 13,199 common to before- and during-differentiation bovine satellite cells. Whereas most of the before- or during-differentiation-specific H3K27ac-marked enhancers were located distally to the transcription start site, the enhancers common to before- and during-differentiation were located both distally and proximally to the transcription start site. The three sets of H3K27ac-marked enhancers were associated with functionally different genes and enriched with different transcription factor binding sites. Specifically, many of the H3K27ac-marked enhancers specific to during-differentiation bovine satellite cells were associated with genes involved in muscle structure and development, and were enriched with binding sites for the MyoD, AP-1, KLF, TEAD, and MEF2 families of transcription factors. A positive role was validated for Fos and FosB, two AP-1 family transcription factors, in the differentiation of bovine satellite cells into myotubes by siRNA-mediated knockdown. CONCLUSIONS Tens of thousands of H3K27ac-marked active enhancers have been identified from bovine satellite cells before or during differentiation. These enhancers contain binding sites not only for transcription factors whose role in satellite cell differentiation is well known but also for transcription factors whose role in satellite cell differentiation is unknown. These enhancers and transcription factors are valuable resources for understanding the complex mechanism that mediates gene expression during satellite cell differentiation. Because satellite cell differentiation is a key step in skeletal muscle growth, the enhancers, the transcription factors, and their target genes identified in this study are also valuable resources for identifying and interpreting skeletal muscle trait-associated DNA variants in cattle.
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12
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Dayanidhi S, Buckner EH, Redmond RS, Chambers HG, Schenk S, Lieber RL. Skeletal muscle maximal mitochondrial activity in ambulatory children with cerebral palsy. Dev Med Child Neurol 2021; 63:1194-1203. [PMID: 33393083 DOI: 10.1111/dmcn.14785] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/19/2020] [Indexed: 12/16/2022]
Abstract
AIM To compare skeletal muscle mitochondrial enzyme activity and mitochondrial content between independently ambulatory children with cerebral palsy (CP) and typically developing children. METHOD Gracilis biopsies were obtained from 12 children during surgery (n=6/group, children with CP: one female, five males, mean age 13y 4mo, SD 5y 1mo, 4y 1mo-17y 10mo; typically developing children: three females, three males, mean age 16y 5mo, SD 1y 4mo, 14y 6mo-18y 2mo). Spectrophotometric enzymatic assays were used to evaluate the activity of mitochondrial electron transport chain complexes. Mitochondrial content was evaluated using citrate synthase assay, mitochondrial DNA copy number, and immunoblots for specific respiratory chain proteins. RESULTS Maximal enzyme activity was significantly (50-80%) lower in children with CP versus typically developing children, for complex I (11nmol/min/mg protein, standard error of the mean [SEM] 1.7 vs 20.7nmol/min/mg protein, SEM 4), complex II (6.9nmol/min/mg protein, SEM 1.2 vs 21nmol/min/mg protein, SEM 2.7), complex III (31.9nmol/min/mg protein, SEM 7.4 vs 72.7nmol/min/mg protein, SEM 7.2), and complex I+III (7.4nmol/min/mg protein, SEM 2.5 vs 31.8nmol/min/mg protein, SEM 9.3). Decreased electron transport chain activity was not the result of lower mitochondrial content. INTERPRETATION Skeletal muscle mitochondrial electron transport chain enzymatic activity but not mitochondrial content is reduced in independently ambulatory children with CP. Decreased mitochondrial oxidative capacity might explain reported increased energetics of movement and fatigue in ambulatory children with CP. What this paper adds Skeletal muscle mitochondrial electron transport chain enzymatic activity is reduced in independently ambulatory children with cerebral palsy (CP). Mitochondrial content appears to be similar between children with CP and typically developing children.
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Affiliation(s)
- Sudarshan Dayanidhi
- Department of Orthopaedic Surgery, University of California, San Diego, CA, USA.,Department of Veterans Affairs Medical Center, San Diego, CA, USA.,Shirley Ryan AbilityLab, Chicago, IL, USA
| | - Elisa H Buckner
- Department of Orthopaedic Surgery, University of California, San Diego, CA, USA.,Biomedical Sciences Program, University of California, San Diego, CA, USA
| | | | - Henry G Chambers
- Department of Orthopaedic Surgery, University of California, San Diego, CA, USA.,Department of Orthopaedics, Rady Children's Hospital, San Diego, CA, USA
| | - Simon Schenk
- Department of Orthopaedic Surgery, University of California, San Diego, CA, USA.,Biomedical Sciences Program, University of California, San Diego, CA, USA
| | - Richard L Lieber
- Department of Orthopaedic Surgery, University of California, San Diego, CA, USA.,Department of Veterans Affairs Medical Center, San Diego, CA, USA.,Shirley Ryan AbilityLab, Chicago, IL, USA.,Department of Bioengineering, University of California, San Diego, CA, USA
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13
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Dayanidhi S. Skeletal Muscle Mitochondrial Physiology in Children With Cerebral Palsy: Considerations for Healthy Aging. Front Neurol 2021; 12:735009. [PMID: 34589051 PMCID: PMC8473886 DOI: 10.3389/fneur.2021.735009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/09/2021] [Indexed: 11/24/2022] Open
Abstract
Skeletal muscle contractile proteins require a constant supply of energy to produce force needed for movement. Energy (ATP) is primarily produced by mitochondrial organelles, located within and around muscle fibers, by oxidative phosphorylation that couples electron flux through the electron transport chain to create a proton gradient across the inner mitochondrial membrane that is in turn used by the ATP synthase. Mitochondrial networks increase in size by biogenesis to increase mitochondrial abundance and activity in response to endurance exercise, while their function and content reduce with constant inactivity, such as during muscle atrophy. During healthy aging, there is an overall decline in mitochondrial activity and abundance, increase in mitochondrial DNA mutations, potential increase in oxidative stress, and reduction in overall muscular capacity. Many of these alterations can be attenuated by consistent endurance exercise. Children with cerebral palsy (CP) have significantly increased energetics of movement, reduced endurance capacity, and increased perceived effort. Recent work in leg muscles in ambulatory children with CP show a marked reduction in mitochondrial function. Arm muscles show that mitochondrial protein content and mitochondria DNA copy number are lower, suggesting a reduction in mitochondrial abundance, along with a reduction in markers for mitochondrial biogenesis. Gene expression networks are reduced for glycolytic and mitochondrial pathways and share similarities with gene networks with aging and chronic inactivity. Given the importance of mitochondria for energy production and changes with aging, future work needs to assess changes in mitochondria across the lifespan in people with CP and the effect of exercise on promoting metabolic health.
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Affiliation(s)
- Sudarshan Dayanidhi
- Shirley Ryan AbilityLab, Chicago, IL, United States.,Department of Physical Medicine and Rehabilitation and Physical Therapy and Human Movement Science, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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14
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Regulation of Energy Substrate Metabolism in Endurance Exercise. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18094963. [PMID: 34066984 PMCID: PMC8124511 DOI: 10.3390/ijerph18094963] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 12/25/2022]
Abstract
The human body requires energy to function. Adenosine triphosphate (ATP) is the cellular currency for energy-requiring processes including mechanical work (i.e., exercise). ATP used by the cells is ultimately derived from the catabolism of energy substrate molecules—carbohydrates, fat, and protein. In prolonged moderate to high-intensity exercise, there is a delicate interplay between carbohydrate and fat metabolism, and this bioenergetic process is tightly regulated by numerous physiological, nutritional, and environmental factors such as exercise intensity and duration, body mass and feeding state. Carbohydrate metabolism is of critical importance during prolonged endurance-type exercise, reflecting the physiological need to regulate glucose homeostasis, assuring optimal glycogen storage, proper muscle fuelling, and delaying the onset of fatigue. Fat metabolism represents a sustainable source of energy to meet energy demands and preserve the ‘limited’ carbohydrate stores. Coordinated neural, hormonal and circulatory events occur during prolonged endurance-type exercise, facilitating the delivery of fatty acids from adipose tissue to the working muscle for oxidation. However, with increasing exercise intensity, fat oxidation declines and is unable to supply ATP at the rate of the exercise demand. Protein is considered a subsidiary source of energy supporting carbohydrates and fat metabolism, contributing to approximately 10% of total ATP turnover during prolonged endurance-type exercise. In this review we present an overview of substrate metabolism during prolonged endurance-type exercise and the regulatory mechanisms involved in ATP turnover to meet the energetic demands of exercise.
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15
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Sport Performance and Manual Therapies: A Review on the Effects on Mitochondrial, Sarcoplasmatic and Ca 2+ Flux Response. Healthcare (Basel) 2021; 9:healthcare9020181. [PMID: 33572071 PMCID: PMC7915302 DOI: 10.3390/healthcare9020181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/26/2021] [Accepted: 02/04/2021] [Indexed: 11/17/2022] Open
Abstract
The present narrative review aims to highlight the possible effects manual therapies could have on cells and mitochondria, as these effects could improve athletic performance management. To this aim, this review summarizes the relationship between mechanical stimulation, with a special focus on physical activity, and cell response based on the most recent mechanobiology findings. Mechanobiology analyzes how cells respond to mechanical stressors coming from the environment. Indeed, endogenous (e.g., blood pressure, heartbeat and gastrointestinal motility) and exogenous (e.g., physical activity and manual therapies) stimuli can induce biochemical and epigenetic modifications that alter protein synthesis with heavy consequences on cell behavior. Mechanical stress can also influence mitochondrial behavior (i.e., biogenesis, autophagy, fusion, fission and energy production), sarcoplasmic response and calcium ion (Ca2+) flux. Since manual therapies have been shown to affect the extracellular matrix, which represents a primary source of mechanical stress that may alter both the cytoskeleton and mitochondrial metabolism, it is conceivable manual therapies could also affect cellular and mitochondrial behavior. Lastly, by suggesting possible directions for future laboratory and clinical studies, the authors expect this review to inspire further research on how manual therapies could affect bioenergetic metabolism and, thus, athletic performance.
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16
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A 12-week aerobic exercise intervention results in improved metabolic function and lower adipose tissue and ectopic fat in high-fat diet fed rats. Biosci Rep 2021; 41:227560. [PMID: 33432988 PMCID: PMC7846962 DOI: 10.1042/bsr20201707] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 12/25/2020] [Accepted: 01/07/2021] [Indexed: 02/06/2023] Open
Abstract
Investigations of long-term exercise interventions in humans to reverse obesity is expensive and is hampered by poor compliance and confounders. In the present study, we investigated intrahepatic and muscle fat, visceral and subcutaneous fat pads, plasma metabolic profile and skeletal muscle inflammatory markers in response to 12-week aerobic exercise in an obese rodent model. Six-week-old male Wistar rats (n=20) were randomized to chow-fed control (Control, n=5), sedentary high-fat diet (HFD, n=5), chow-fed exercise (Exercise, n=5) and HFD-fed exercise (HFD+Exercise, n=5) groups. The exercise groups were subjected to 12 weeks of motorized treadmill running at a speed of 18 m/min for 30 min/day. Differences in post-intervention measures were assessed by analysis of covariance (ANCOVA), adjusted for baseline bodyweight and pre-intervention measures, where available. Post-hoc analyses were performed with Bonferroni correction. Plasma metabolic profile was worsened and fat pads, ectopic fat in muscle and liver and inflammatory markers in skeletal muscle were elevated in sedentary HFD-fed animals relative to chow-fed controls. HFD+Exercise animals had significantly lower leptin (P=0.0004), triglycerides (P=0.007), homeostatic model assessment of insulin resistance (HOMA-IR; P=0.065), intramyocellular lipids (IMCLs; P=0.003), intrahepatic lipids (IHLs; P<0.0001), body fat% (P=0.001), subcutaneous adipose tissue (SAT; P<0.0001), visceral adipose (P<0.0001) and total fat mass (P<0.0001), relative to sedentary HFD-fed animals, despite only modestly lower bodyweight. Messenger RNA (mRNA) expression of inflammatory markers Interleukin 6 (IL6) and Tumor necrosis factor α (TNFα) were also reduced with aerobic exercise in skeletal muscle. Our results suggest that 12 weeks of aerobic exercise training is effective in improving metabolic health, fat depots, ectopic fat and inflammation even against a high-fat dietary background.
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17
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Miller VJ, LaFountain RA, Barnhart E, Sapper TS, Short J, Arnold WD, Hyde PN, Crabtree CD, Kackley ML, Kraemer WJ, Villamena FA, Volek JS. A ketogenic diet combined with exercise alters mitochondrial function in human skeletal muscle while improving metabolic health. Am J Physiol Endocrinol Metab 2020; 319:E995-E1007. [PMID: 32985255 DOI: 10.1152/ajpendo.00305.2020] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Animal data indicate that ketogenic diets are associated with improved mitochondrial function, but human data are lacking. We aimed to characterize skeletal muscle mitochondrial changes in response to a ketogenic diet combined with exercise training in healthy individuals. Twenty-nine physically active adults completed a 12-wk supervised exercise program after self-selection into a ketogenic diet (KD, n = 15) group or maintenance of their habitual mixed diet (MD, n = 14). Measures of metabolic health and muscle biopsies (vastus lateralis) were obtained before and after the intervention. Mitochondria were isolated from muscle and studied after exposure to carbohydrate (pyruvate), fat (palmitoyl-l-carnitine), and ketone (β-hydroxybutyrate+acetoacetate) substrates. Compared with MD, the KD resulted in increased whole body resting fat oxidation (P < 0.001) and decreased fasting insulin (P = 0.019), insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR), P = 0.022], and visceral fat (P < 0.001). The KD altered mitochondrial function as evidenced by increases in mitochondrial respiratory control ratio (19%, P = 0.009), ATP production (36%, P = 0.028), and ATP/H2O2 (36%, P = 0.033) with the fat-based substrate. ATP production with the ketone-based substrate was four to eight times lower than with other substrates, indicating minimal oxidation. The KD resulted in a small decrease in muscle glycogen (14%, P = 0.035) and an increase in muscle triglyceride (81%, P = 0.006). These results expand our understanding of human adaptation to a ketogenic diet combined with exercise. In conjunction with weight loss, we observed altered skeletal muscle mitochondrial function and efficiency, an effect that may contribute to the therapeutic use of ketogenic diets in various clinical conditions, especially those associated with insulin resistance.
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Affiliation(s)
- Vincent J Miller
- OSU Interdisciplinary PhD Program in Nutrition, Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | | | - Emily Barnhart
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | - Teryn S Sapper
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | - Jay Short
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | - W David Arnold
- Department of Neurology, Wexner Medical Center, The Ohio State University, Columbus, Ohio
| | - Parker N Hyde
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | | | - Madison L Kackley
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | - William J Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
| | - Frederick A Villamena
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, Ohio
| | - Jeff S Volek
- OSU Interdisciplinary PhD Program in Nutrition, Department of Human Sciences, The Ohio State University, Columbus, Ohio
- Department of Human Sciences, The Ohio State University, Columbus, Ohio
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18
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Wright TJ, Davis RW, Holser RR, Hückstädt LA, Danesi CP, Porter C, Widen SG, Williams TM, Costa DP, Sheffield-Moore M. Changes in Northern Elephant Seal Skeletal Muscle Following Thirty Days of Fasting and Reduced Activity. Front Physiol 2020; 11:564555. [PMID: 33123026 PMCID: PMC7573231 DOI: 10.3389/fphys.2020.564555] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/17/2020] [Indexed: 12/21/2022] Open
Abstract
Northern elephant seals (NES, Mirounga angustirostris) undergo an annual molt during which they spend ∼40 days fasting on land with reduced activity and lose approximately one-quarter of their body mass. Reduced activity and muscle load in stereotypic terrestrial mammalian models results in decreased muscle mass and capacity for force production and aerobic metabolism. However, the majority of lost mass in fasting female NES is from fat while muscle mass is largely preserved. Although muscle mass is preserved, potential changes to the metabolic and contractile capacity are unknown. To assess potential changes in NES skeletal muscle during molt, we collected muscle biopsies from 6 adult female NES before the molt and after ∼30 days at the end of the molt. Skeletal muscle was assessed for respiratory capacity using high resolution respirometry, and RNA was extracted to assess changes in gene expression. Despite a month of reduced activity, fasting, and weight loss, skeletal muscle respiratory capacity was preserved with no change in OXPHOS respiratory capacity. Molt was associated with 162 upregulated genes including those favoring lipid metabolism. We identified 172 downregulated genes including those coding for ribosomal proteins and genes associated with skeletal muscle force transduction and glucose metabolism. Following ∼30 days of molt, NES skeletal muscle metabolic capacity is preserved although mechanotransduction may be compromised. In the absence of exercise stimulus, fasting-induced shifts in muscle metabolism may stimulate pathways associated with preserving the mass and metabolic capacity of slow oxidative muscle.
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Affiliation(s)
- Traver J Wright
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, United States.,Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Randall W Davis
- Department of Marine Biology, Texas A&M University, Galveston, TX, United States
| | - Rachel R Holser
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Luis A Hückstädt
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Christopher P Danesi
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Craig Porter
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
| | - Terrie M Williams
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Daniel P Costa
- Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Melinda Sheffield-Moore
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, United States.,Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
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19
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Jeppesen TD. Aerobic Exercise Training in Patients With mtDNA-Related Mitochondrial Myopathy. Front Physiol 2020; 11:349. [PMID: 32508662 PMCID: PMC7253634 DOI: 10.3389/fphys.2020.00349] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 03/26/2020] [Indexed: 01/15/2023] Open
Abstract
In patients with mitochondrial DNA (mtDNA) mutation, a pathogenic mtDNA mutation is heteroplasmically distributed among tissues. The ratio between wild-type and mutated mtDNA copies determines the mtDNA mutation load of the tissue, which correlates inversively with oxidative capacity of the tissue. In patients with mtDNA mutation, the mutation load is often very high in skeletal muscle compared to other tissues. Additionally, skeletal muscle can increase its oxygen demand up to 100-fold from rest to exercise, which is unmatched by any other tissue. Thus, exercise intolerance is the most common symptom in patients with mtDNA mutation. The impaired oxidative capacity in skeletal muscle in patients with mtDNA mutation results in limitation in physical capacity that interferes with daily activities and impairs quality of life. Additionally, patients with mitochondrial disease due to mtDNA mutation often live a sedentary lifestyle, which further impair oxidative capacity and exercise tolerance. Since aerobic exercise training increase mitochondrial function and volume density in healthy individuals, studies have investigated if aerobic training could be used to counteract the progressive exercise intolerance in patients with mtDNA mutation. Overall studies investigating the effect of aerobic training in patients with mtDNA mutation have shown that aerobic training is an efficient way to improve oxidative capacity in this condition, and aerobic training seems to be safe even for patients with high mtDNA mutation in skeletal muscle.
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Affiliation(s)
- Tina Dysgaard Jeppesen
- Copenhagen Neuromuscular Clinic, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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20
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Salerno GRF, Bortolini MAT, Gomes RCT, Feitosa SM, Simões MJ, Zanoteli E, Castanho FL, Castro RA. The molecular effects of electrical stimulation on the muscle components of the urethra of female rats after trauma by vaginal distention. Neurourol Urodyn 2019; 39:576-585. [DOI: 10.1002/nau.24243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 11/18/2019] [Indexed: 12/27/2022]
Affiliation(s)
- Gisela R. F. Salerno
- Department of Gynecology, Sector of Urogynecology and Vaginal Surgery Universidade Federal de São Paulo São Paulo Brazil
| | - Maria A. T. Bortolini
- Department of Gynecology, Sector of Urogynecology and Vaginal Surgery Universidade Federal de São Paulo São Paulo Brazil
| | - Regina C. T. Gomes
- Histology and Structural Biology Division, Department of Morphology and Genetics Universidade Federal de São Paulo São Paulo Brazil
| | - Suellen M. Feitosa
- Department of Gynecology, Sector of Urogynecology and Vaginal Surgery Universidade Federal de São Paulo São Paulo Brazil
| | - Manuel J. Simões
- Histology and Structural Biology Division, Department of Morphology and Genetics Universidade Federal de São Paulo São Paulo Brazil
| | - Edmar Zanoteli
- Department of Neurology, Faculdade de Medicina da Universidade de São Paulo Hospital das Clínicas São Paulo Brazil
| | - Fernanda L. Castanho
- Department of Gynecology, Sector of Urogynecology and Vaginal Surgery Universidade Federal de São Paulo São Paulo Brazil
| | - Rodrigo A. Castro
- Department of Gynecology, Sector of Urogynecology and Vaginal Surgery Universidade Federal de São Paulo São Paulo Brazil
- Sector of Gynecology Hospital Samaritano São Paulo Brazil
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Mitochondrial dysfunction is the cause of one of the earliest changes seen on magnetic resonance imaging in Charcot neuroarthopathy - Oedema of the small muscles in the foot. Med Hypotheses 2019; 134:109439. [PMID: 31644972 DOI: 10.1016/j.mehy.2019.109439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 10/17/2019] [Indexed: 12/20/2022]
Abstract
The hypothesis laid out in this thesis states that the early changes seen on an MR imaging in those with early Charcot neuroarthopathy may be due to mitochondrial dysfunction. In a Charcot foot, there is movement between bones. In an attempt to prevent this movement, the small muscles of the foot contract continuously when the foot is weight bearing. This contraction takes energy in the form of ATP. However, the reduction of glucose transport into the muscle cells due to insulin resistance / insufficiency, leads to reduction in the ATP producing capacity of the mitochondria. The ATP depletion affects the cell membrane gradient leading to mitochondrial and cellular swelling. These early cellular changes could then be picked up with MR imaging as muscle oedema.
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22
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Bland KA, Kirkham AA, Bovard J, Shenkier T, Zucker D, McKenzie DC, Davis MK, Gelmon KA, Campbell KL. Effect of Exercise on Taxane Chemotherapy-Induced Peripheral Neuropathy in Women With Breast Cancer: A Randomized Controlled Trial. Clin Breast Cancer 2019; 19:411-422. [PMID: 31601479 DOI: 10.1016/j.clbc.2019.05.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/10/2019] [Accepted: 05/24/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND Chemotherapy-induced peripheral neuropathy (CIPN) is a dose-limiting adverse effect of taxanes. We sought to evaluate the effect of exercise on taxane CIPN in women with breast cancer. PATIENTS AND METHODS Women (n = 27) were randomized to immediate exercise (IE, during taxane chemotherapy) or delayed exercise (DE, after chemotherapy). Supervised aerobic, resistance, and balance training was offered 3 days a week for 8-12 weeks. CIPN symptoms and quality of life were assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ) C30 and CIPN20 (scored from 0 to 100). The percentage of participants reporting moderate to severe sensory symptoms ('3/4' or '4/4' for CIPN20 sensory items) was also evaluated, along with clinical sensory testing at the lower limb (vibration sense and pinprick). Taxane treatment adherence, including relative dose intensity, was extracted from patient medical records. Assessments occurred at: baseline (before taxane chemotherapy), pre-cycle 4 (before the final taxane cycle), the end of chemotherapy, and follow-up (10-15 weeks after chemotherapy). RESULTS No differences in the EORTC QLQ CIPN20 symptom scores were detected between groups at any time point. At pre-cycle 4, there was a significant difference between groups in patient-reported moderate to severe numbness in the toes or feet (IE: n = 1, 9%, DE: n = 7, 50%, P = .04) and impaired vibration sense in the feet (IE: n = 2, 18%, DE: n = 10, 83%, P < .01). Overall global health status/quality of life was higher in IE compared to DE at the end of chemotherapy (P = .05), yet both groups had worse CIPN20 sensory (Δ24.3 ± 4.6, P < .01) and motor symptom scores (Δ10.5 ± 1.9, P < .01) relative to baseline. By the end of chemotherapy, no differences between groups were found for moderate to severe numbness in the toes or feet (P = 1.0) or impaired vibration sense in the feet (P = .71). More IE participants received ≥ 85% relative dose intensity (IE: n = 12, 100%, DE: n = 10, 67%, P < .05). CONCLUSION Exercise may attenuate CIPN over the course of taxane chemotherapy and possibly improve taxane adherence in women with breast cancer. These findings, as well as whether exercise can attenuate CIPN by the end of taxane chemotherapy, should be confirmed in larger trials.
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Affiliation(s)
- Kelcey A Bland
- Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Amy A Kirkham
- Department of Biomedical Engineering, University of Alberta, Edmonton, Canada
| | - Joshua Bovard
- School of Kinesiology, University of British Columbia, Vancouver, Canada
| | | | - David Zucker
- Swedish Cancer Institute, Swedish Medical Center, Seattle, WA
| | - Donald C McKenzie
- School of Kinesiology, University of British Columbia, Vancouver, Canada
| | - Margot K Davis
- Division of Cardiology, Gordon & Leslie Diamond Health Care Centre, University of British Columbia, Vancouver, Canada
| | | | - Kristin L Campbell
- Rehabilitation Sciences, University of British Columbia, Vancouver, Canada; Department of Physical Therapy, University of British Columbia, Vancouver, Canada.
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Berg J, Undebakke V, Rasch-Halvorsen Ø, Aakerøy L, Sandbakk Ø, Tjønna AE. Comparison of Mitochondrial Respiration in M. triceps brachii and M. vastus lateralis Between Elite Cross-Country Skiers and Physically Active Controls. Front Physiol 2019; 10:365. [PMID: 31024334 PMCID: PMC6461012 DOI: 10.3389/fphys.2019.00365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 03/15/2019] [Indexed: 11/13/2022] Open
Abstract
Rationale The main purposes of this study were to compare mitochondrial respiration in M. triceps brachii and M. vastus lateralis between elite cross-country (XC) skiers and physically active controls (CON), and to explore the associations between mitochondrial respiration in these muscles and peak oxygen uptake ( V ˙ O2peak) in arm- and leg-dominant exercise modes. Methods Thirteen male elite XC skiers (age: 25 ± 4; peak oxygen uptake ( V ˙ O2peak): 75.5 ± 4.2 mL⋅kg-1⋅min-1) and twelve CON (age: 26 ± 3; V ˙ O2peak: 57.2 ± 6.4 mL⋅kg-1⋅min-1) had microbiopsies taken from M. vastus lateralis and M. triceps brachii, which were analyzed for various measures of mitochondrial respiration using high-resolution respirometry. Thereafter, all participants tested V ˙ O2peak in both running (RUN) and upper body poling (UBP). Results XC skiers had generally higher mitochondrial respiration in M. triceps brachii compared to CON (P < 0.001), whereas no significant group-differences in mitochondrial respiration in M. vastus lateralis were revealed. XC skiers had higher mitochondrial respiration in M. triceps brachii compared to M. vastus lateralis (P = 0.005-0.058), whereas in CON, most mitochondrial respiration measures were higher in M. vastus lateralis than in M. triceps brachii (P < 0.01). When all athletes were pooled, there was a strong positive correlation between V ˙ O2peak in UBP and mitochondrial respiration in M. triceps brachii on several measures (P < 0.01), whereas no correlation was found for RUN. Conclusion The higher mitochondrial respiration found in M. triceps brachii compared to M. vastus lateralis among our elite XC skiers demonstrates the potential for the arm muscles to adapt to aerobic endurance training. The opposite pattern found in CON, clearly showed lower mitochondrial respiration in M. triceps brachii compared to XC skiers, whereas respiration in M. vastus lateralis did not differ between groups. The strong positive correlation between mitochondrial respiration in M. triceps brachii and V ˙ O2peak in UBP indicate that arm muscles' respiratory function may be a limiting factor for V ˙ O2peak in arm-dominant exercise modes.
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Affiliation(s)
- Jonathan Berg
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Vidar Undebakke
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Øystein Rasch-Halvorsen
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.,Clinic of Thoracic and Occupational Medicine, St. Olav's University Hospital, Trondheim, Norway
| | - Lars Aakerøy
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.,Clinic of Thoracic and Occupational Medicine, St. Olav's University Hospital, Trondheim, Norway
| | - Øyvind Sandbakk
- Centre for Elite Sports Research, Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
| | - Arnt Erik Tjønna
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
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24
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Leng X, Ji X, Hou Y, Settlage R, Jiang H. Roles of the proteasome and inhibitor of DNA binding 1 protein in myoblast differentiation. FASEB J 2019; 33:7403-7416. [PMID: 30865843 DOI: 10.1096/fj.201800574rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
This study was conducted to further understand the mechanism that controls myoblast differentiation, a key step in skeletal muscle formation. RNA sequencing of primary bovine myoblasts revealed many genes encoding the ubiquitin-proteasome system were up-regulated during myoblast differentiation. This up-regulation was accompanied by increased proteasomal activity. Treating myoblasts with the proteasome-specific inhibitor lactacystin impeded myoblast differentiation. Adenovirus-mediated overexpression of inhibitor of DNA binding 1 (ID1) protein inhibited myoblast differentiation too. Further experiments were conducted to determine whether the proteasome promotes myoblast differentiation by degrading ID1 protein. Both ID1 protein and mRNA expression decreased during myoblast differentiation. However, treating myoblasts with lactacystin reversed the decrease in ID1 protein but not in ID1 mRNA expression. Surprisingly, this reversal was not observed when myoblasts were also treated with the mRNA translation inhibitor cycloheximide. Direct incubation of ID1 protein with proteasomes from myoblasts did not show differentiation stage-associated degradation of ID1 protein. Furthermore, ubiquitinated ID1 protein was not detected in lactacystin-treated myoblasts. Overall, the results of this study suggest that, during myoblast differentiation, the proteasomal activity is up-regulated to further myoblast differentiation and that the increased proteasomal activity improves myoblast differentiation partly by inhibiting the synthesis, not the degradation, of ID1 protein.-Leng, X., Ji, X., Hou, Y., Settlage, R., Jiang, H. Roles of the proteasome and inhibitor of DNA binding 1 protein in myoblast differentiation.
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Affiliation(s)
- Xinyan Leng
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Xu Ji
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, Virginia, USA.,College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China; and
| | - Yuguo Hou
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | - Robert Settlage
- Advanced Research Computing Unit, Division of Information Technology, Virginia Tech, Blacksburg, Virginia, USA
| | - Honglin Jiang
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, Virginia, USA
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25
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Silva LA, Tromm CB, Doyenart R, Thirupathi A, Silveira PCL, Pinho RA. Effects of different frequencies of physical training on electron transport chain and oxidative damage in healthy mice. MOTRIZ: REVISTA DE EDUCACAO FISICA 2018. [DOI: 10.1590/s1980-6574201800040008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Luciano A. Silva
- Universidade do Extremo Sul Catarinense, Brazil; Escola superiror de Criciúma, Brazil; Centro Universitario Barriga Verde, Brazil
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26
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Rezvyakov PN, Shaimardanova GF, Lisukov AN, Kuznetsov MS, Islamov RR, Nikolskiy EE. Morphological Study of Myelinated Fibers of the Sciatic Nerve in Mice after Space Flight and Readaptation to the Conditions of Earth Gravity. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2018; 482:174-177. [PMID: 30402752 DOI: 10.1134/s0012496618050101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Indexed: 11/23/2022]
Abstract
We revealed a decrease in the thickness of the myelin sheath and myelin delamination in the tibial nerve of C57BL/6N mice after a 30-day flight aboard the biosatellite Bion-M1. The processes of myelin degeneration continued for seven days after return of the animals to Earth and adaptation to the conditions of natural gravity. Our data add to hypothesis on the role of neurogenic component in pathogenesis of hypogravity motor syndrome.
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Affiliation(s)
- P N Rezvyakov
- Kazan State Medical University, Kazan, Tatarstan, Russia.
| | - G F Shaimardanova
- Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Sciences, Kazan, Tatarstan, Russia
| | - A N Lisukov
- Kazan State Medical University, Kazan, Tatarstan, Russia
| | - M S Kuznetsov
- Kazan State Medical University, Kazan, Tatarstan, Russia
| | - R R Islamov
- Kazan State Medical University, Kazan, Tatarstan, Russia.,Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Sciences, Kazan, Tatarstan, Russia
| | - E E Nikolskiy
- Kazan State Medical University, Kazan, Tatarstan, Russia.,Kazan Institute of Biochemistry and Biophysics, Kazan Scientific Center, Russian Academy of Sciences, Kazan, Tatarstan, Russia.,Kazan (Privolzhskii) Federal University, Kazan, Tatarstan, Russia
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27
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Ørtenblad N, Nielsen J, Boushel R, Söderlund K, Saltin B, Holmberg HC. The Muscle Fiber Profiles, Mitochondrial Content, and Enzyme Activities of the Exceptionally Well-Trained Arm and Leg Muscles of Elite Cross-Country Skiers. Front Physiol 2018; 9:1031. [PMID: 30116201 PMCID: PMC6084043 DOI: 10.3389/fphys.2018.01031] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/11/2018] [Indexed: 01/11/2023] Open
Abstract
As one of the most physically demanding sports in the Olympic Games, cross-country skiing poses considerable challenges with respect to both force generation and endurance during the combined upper- and lower-body effort of varying intensity and duration. The isoforms of myosin in skeletal muscle have long been considered not only to define the contractile properties, but also to determine metabolic capacities. The current investigation was designed to explore the relationship between these isoforms and metabolic profiles in the arms (triceps brachii) and legs (vastus lateralis) as well as the range of training responses in the muscle fibers of elite cross-country skiers with equally and exceptionally well-trained upper and lower bodies. The proportion of myosin heavy chain (MHC)-1 was higher in the leg (58 ± 2% [34-69%]) than arm (40 ± 3% [24-57%]), although the mitochondrial volume percentages [8.6 ± 1.6 (leg) and 9.0 ± 2.0 (arm)], and average number of capillaries per fiber [5.8 ± 0.8 (leg) and 6.3 ± 0.3 (arm)] were the same. In these comparable highly trained leg and arm muscles, the maximal citrate synthase (CS) activity was the same. Still, 3-hydroxy-acyl-CoA-dehydrogenase (HAD) capacity was 52% higher (P < 0.05) in the leg compared to arm muscles, suggesting a relatively higher capacity for lipid oxidation in leg muscle, which cannot be explained by the different fiber type distributions. For both limbs combined, HAD activity was correlated with the content of MHC-1 (r2 = 0.32, P = 0.011), whereas CS activity was not. Thus, in these highly trained cross-country skiers capillarization of and mitochondrial volume in type 2 fiber can be at least as high as in type 1 fibers, indicating a divergence between fiber type pattern and aerobic metabolic capacity. The considerable variability in oxidative metabolism with similar MHC profiles provides a new perspective on exercise training. Furthermore, the clear differences between equally well-trained arm and leg muscles regarding HAD activity cannot be explained by training status or MHC distribution, thereby indicating an intrinsic metabolic difference between the upper and lower body. Moreover, trained type 1 and type 2A muscle fibers exhibited similar aerobic capacity regardless of whether they were located in an arm or leg muscle.
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Affiliation(s)
- Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster, University of Southern Denmark, Odense, Denmark.,School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Joachim Nielsen
- Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster, University of Southern Denmark, Odense, Denmark
| | - Robert Boushel
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Karin Söderlund
- Åstrand Laboratory, The Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Bengt Saltin
- Copenhagen Muscle Research Centre, Copenhagen, Denmark
| | - Hans-Christer Holmberg
- Swedish Winter Sports Research Centre, Mid Sweden University, Östersund, Sweden.,School of Sport Sciences, UiT The Arctic University of Norway, Tromsø, Norway
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28
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Heydemann A. Skeletal Muscle Metabolism in Duchenne and Becker Muscular Dystrophy-Implications for Therapies. Nutrients 2018; 10:nu10060796. [PMID: 29925809 PMCID: PMC6024668 DOI: 10.3390/nu10060796] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/14/2018] [Accepted: 06/16/2018] [Indexed: 02/06/2023] Open
Abstract
The interactions between nutrition and metabolism and skeletal muscle have long been known. Muscle is the major metabolic organ—it consumes more calories than other organs—and therefore, there is a clear need to discuss these interactions and provide some direction for future research areas regarding muscle pathologies. In addition, new experiments and manuscripts continually reveal additional highly intricate, reciprocal interactions between metabolism and muscle. These reciprocal interactions include exercise, age, sex, diet, and pathologies including atrophy, hypoxia, obesity, diabetes, and muscle myopathies. Central to this review are the metabolic changes that occur in the skeletal muscle cells of muscular dystrophy patients and mouse models. Many of these metabolic changes are pathogenic (inappropriate body mass changes, mitochondrial dysfunction, reduced adenosine triphosphate (ATP) levels, and increased Ca2+) and others are compensatory (increased phosphorylated AMP activated protein kinase (pAMPK), increased slow fiber numbers, and increased utrophin). Therefore, reversing or enhancing these changes with therapies will aid the patients. The multiple therapeutic targets to reverse or enhance the metabolic pathways will be discussed. Among the therapeutic targets are increasing pAMPK, utrophin, mitochondrial number and slow fiber characteristics, and inhibiting reactive oxygen species. Because new data reveals many additional intricate levels of interactions, new questions are rapidly arising. How does muscular dystrophy alter metabolism, and are the changes compensatory or pathogenic? How does metabolism affect muscular dystrophy? Of course, the most profound question is whether clinicians can therapeutically target nutrition and metabolism for muscular dystrophy patient benefit? Obtaining the answers to these questions will greatly aid patients with muscular dystrophy.
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Affiliation(s)
- Ahlke Heydemann
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, USA.
- Center for Cardiovascular Research, The University of Illinois at Chicago, Chicago, IL 60612, USA.
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29
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Smolina N, Bruton J, Kostareva A, Sejersen T. Assaying Mitochondrial Respiration as an Indicator of Cellular Metabolism and Fitness. Methods Mol Biol 2018; 1601:79-87. [PMID: 28470519 DOI: 10.1007/978-1-4939-6960-9_7] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Mitochondrial respiration is the most important generator of cellular energy under most circumstances. It is a process of energy conversion of substrates into ATP. The Seahorse equipment allows measuring oxygen consumption rate (OCR) in living cells and estimates key parameters of mitochondrial respiration in real-time mode. Through use of mitochondrial inhibitors, four key mitochondrial respiration parameters can be measured: basal, ATP production-linked, maximal, and proton leak-linked OCR. This approach requires application of mitochondrial inhibitors-oligomycin to block ATP synthase, FCCP-to make the inner mitochondrial membrane permeable for protons and allow maximum electron flux through the electron transport chain, and rotenone and antimycin A-to inhibit complexes I and III, respectively. This chapter describes the protocol of OCR assessment in the culture of primary myotubes obtained upon satellite cell fusion.
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Affiliation(s)
- Natalia Smolina
- Karolinska Institutet, Stockholm, Sweden. .,Federal Almazov North-West Medical Research Centre, Akkuratova Str. 2, Saint Petersburg, 197341, Russia.
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30
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Associations of Mitochondrial Fatty Acid Oxidation with Body Fat in Premenopausal Women. J Nutr Metab 2017; 2017:7832057. [PMID: 29204295 PMCID: PMC5674507 DOI: 10.1155/2017/7832057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 09/07/2017] [Accepted: 09/17/2017] [Indexed: 11/24/2022] Open
Abstract
Higher in vivo fatty acid (FA) oxidation rates have been reported in obese individuals compared to lean counterparts; however whether this reflects a shift in substrate-specific oxidative capacity at the level of the skeletal muscle mitochondria has not been examined. The purpose of this study was to test the hypothesis that in situ measures of skeletal muscle mitochondria FA oxidation would be positively associated with total body fat. Participants were 38 premenopausal women (BMI = 26.5 ± 4.3 kg/m2). Total and regional fat were assessed by dual-energy X-ray absorptiometry (DXA). Mitochondrial FA oxidation was assessed in permeabilized myofibers using high-resolution respirometry and a palmitoyl carnitine substrate. We found positive associations of total fat mass with State 3 (ADP-stimulated respiration) (r = 0.379, p < 0.05) and the respiratory control ratio (RCR, measure of mitochondrial coupling) (r = 0.348, p < 0.05). When participants were dichotomized by high or low body fat percent, participants with high total body fat displayed a higher RCR compared to those with low body fat (p < 0.05). There were no associations between any measure of regional fat and mitochondrial FA oxidation independent of total fat mass. In conclusion, greater FA oxidation in obesity may reflect molecular processes that enhance FA oxidation capacity at the mitochondrial level.
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31
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Clawson LL, Cudkowicz M, Krivickas L, Brooks BR, Sanjak M, Allred P, Atassi N, Swartz A, Steinhorn G, Uchil A, Riley KM, Yu H, Schoenfeld DA, Maragakis NJ. A randomized controlled trial of resistance and endurance exercise in amyotrophic lateral sclerosis. Amyotroph Lateral Scler Frontotemporal Degener 2017; 19:250-258. [PMID: 29191052 DOI: 10.1080/21678421.2017.1404108] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Evaluate the safety and tolerability of resistance and endurance exercise in ALS participants as measured by their ability to complete this six-month study. METHODS Participants were randomized to Resistance, Endurance, or Stretching/Range of Motion (SROM the exercise regimen prescribed for most ALS patients) exercises. All exercises were performed at home with an individualized regimen designed by a physical therapist trained in ALS management. Primary outcome measures were tolerability of the exercises at 24 weeks defined by 50% of participants completing at least 50% of the prescribed exercise regimen. Secondary outcome measures included the ALSFRS-R, pulmonary FVC, and other measures of ALS function. RESULTS At 12 and 24 weeks, all three exercise regimens were tolerated according to our pre-specified criteria. Compliance to the prescribed exercise regimen was the highest in the resistance and SROM arms of the study. All three forms of exercise were considered safe as there were no differences in the rates of disease progression among groups. There were no differences in the secondary outcome measures and feasibility for evaluating these measures was successful. In a post-hoc analysis, there was a trend towards fewer falls in the Resistance and Endurance groups. CONCLUSIONS This study demonstrates that SROM, resistance, and endurance exercise are all safe to be performed with the specified regimen without any worsening of outcomes as related to ALS function. All three forms of exercise were tolerated with resistance and SROM exercises showing the highest compliance over the 24 week-period.
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Affiliation(s)
- Lora L Clawson
- a Department of Neurology, School of Medicine , Johns Hopkins University , Baltimore , MD , USA
| | - Merit Cudkowicz
- b Neurology Clinical Research Institute , Massachusetts General Hospital , Boston , MA , USA
| | - Lisa Krivickas
- c Department of Physical Medicine and Rehabilitation , Harvard University , Boston , MA , USA
| | - Benjamin R Brooks
- d Carolinas Neuromuscular/ALS-MDA Center, Department of Neurology, Neuroscience and Spine Institute , Carolinas HealthCare System , Charlotte , NC , USA , and
| | - Mohammed Sanjak
- d Carolinas Neuromuscular/ALS-MDA Center, Department of Neurology, Neuroscience and Spine Institute , Carolinas HealthCare System , Charlotte , NC , USA , and
| | - Peggy Allred
- e Department of Neurology, Cedars-Sinai Medical Center , Los Angeles , CA , USA
| | - Nazem Atassi
- b Neurology Clinical Research Institute , Massachusetts General Hospital , Boston , MA , USA
| | - Amy Swartz
- b Neurology Clinical Research Institute , Massachusetts General Hospital , Boston , MA , USA
| | - Gabrielle Steinhorn
- a Department of Neurology, School of Medicine , Johns Hopkins University , Baltimore , MD , USA
| | - Alpa Uchil
- a Department of Neurology, School of Medicine , Johns Hopkins University , Baltimore , MD , USA
| | - Kristen M Riley
- a Department of Neurology, School of Medicine , Johns Hopkins University , Baltimore , MD , USA
| | - Hong Yu
- b Neurology Clinical Research Institute , Massachusetts General Hospital , Boston , MA , USA
| | - David A Schoenfeld
- b Neurology Clinical Research Institute , Massachusetts General Hospital , Boston , MA , USA
| | - Nicholas J Maragakis
- a Department of Neurology, School of Medicine , Johns Hopkins University , Baltimore , MD , USA
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32
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Zampieri S, Mammucari C, Romanello V, Barberi L, Pietrangelo L, Fusella A, Mosole S, Gherardi G, Höfer C, Löfler S, Sarabon N, Cvecka J, Krenn M, Carraro U, Kern H, Protasi F, Musarò A, Sandri M, Rizzuto R. Physical exercise in aging human skeletal muscle increases mitochondrial calcium uniporter expression levels and affects mitochondria dynamics. Physiol Rep 2017; 4:4/24/e13005. [PMID: 28039397 PMCID: PMC5210373 DOI: 10.14814/phy2.13005] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 09/26/2016] [Accepted: 09/26/2016] [Indexed: 01/04/2023] Open
Abstract
Age‐related sarcopenia is characterized by a progressive loss of muscle mass with decline in specific force, having dramatic consequences on mobility and quality of life in seniors. The etiology of sarcopenia is multifactorial and underlying mechanisms are currently not fully elucidated. Physical exercise is known to have beneficial effects on muscle trophism and force production. Alterations of mitochondrial Ca2+ homeostasis regulated by mitochondrial calcium uniporter (MCU) have been recently shown to affect muscle trophism in vivo in mice. To understand the relevance of MCU‐dependent mitochondrial Ca2+ uptake in aging and to investigate the effect of physical exercise on MCU expression and mitochondria dynamics, we analyzed skeletal muscle biopsies from 70‐year‐old subjects 9 weeks trained with either neuromuscular electrical stimulation (ES) or leg press. Here, we demonstrate that improved muscle function and structure induced by both trainings are linked to increased protein levels of MCU. Ultrastructural analyses by electron microscopy showed remodeling of mitochondrial apparatus in ES‐trained muscles that is consistent with an adaptation to physical exercise, a response likely mediated by an increased expression of mitochondrial fusion protein OPA1. Altogether these results indicate that the ES‐dependent physiological effects on skeletal muscle size and force are associated with changes in mitochondrial‐related proteins involved in Ca2+ homeostasis and mitochondrial shape. These original findings in aging human skeletal muscle confirm the data obtained in mice and propose MCU and mitochondria‐related proteins as potential pharmacological targets to counteract age‐related muscle loss.
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Affiliation(s)
- Sandra Zampieri
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria .,Venetian Institute of Molecular Medicine, Padova, Italy.,Department of Biomedical Science, University of Padova, Padova, Italy
| | | | | | - Laura Barberi
- DAHFMO-Unit of Histology and Medical Embryology, IIM, Institute Pasteur Cenci-Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Laura Pietrangelo
- Department of Neuroscience, Imaging and Clinical Sciences, CeSI-Met - Center for Research on Aging and Translational Medicine & DNICS University G. d'Annunzio, Chieti, Italy
| | - Aurora Fusella
- Department of Neuroscience, Imaging and Clinical Sciences, CeSI-Met - Center for Research on Aging and Translational Medicine & DNICS University G. d'Annunzio, Chieti, Italy
| | - Simone Mosole
- Department of Biomedical Science, University of Padova, Padova, Italy
| | - Gaia Gherardi
- Department of Biomedical Science, University of Padova, Padova, Italy
| | - Christian Höfer
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Stefan Löfler
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Nejc Sarabon
- Science and Research Centre, Institute for Kinesiology Research, University of Primorska, Koper, Slovenia
| | - Jan Cvecka
- Faculty of Physical Education and Sport, Comenius University, Bratislava, Slovakia
| | - Matthias Krenn
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Ugo Carraro
- Institute of Electrodynamics, Microwave and Circuit Engineering, Vienna University of Technology, Vienna, Austria.,IRCCS Fondazione Ospedale San Camillo, Venezia, Italy
| | - Helmut Kern
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Feliciano Protasi
- Department of Neuroscience, Imaging and Clinical Sciences, CeSI-Met - Center for Research on Aging and Translational Medicine & DNICS University G. d'Annunzio, Chieti, Italy
| | - Antonio Musarò
- DAHFMO-Unit of Histology and Medical Embryology, IIM, Institute Pasteur Cenci-Bolognetti, Sapienza University of Rome, Rome, Italy.,Center for Life Nano Science at Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Marco Sandri
- Venetian Institute of Molecular Medicine, Padova, Italy.,Department of Biomedical Science, University of Padova, Padova, Italy
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Michaletti A, Gioia M, Tarantino U, Zolla L. Effects of microgravity on osteoblast mitochondria: a proteomic and metabolomics profile. Sci Rep 2017; 7:15376. [PMID: 29133864 PMCID: PMC5684136 DOI: 10.1038/s41598-017-15612-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 10/30/2017] [Indexed: 01/21/2023] Open
Abstract
The response of human primary osteoblasts exposed to simulated microgravity has been investigated and analysis of metabolomic and proteomic profiles demonstrated a prominent dysregulation of mitochondrion homeostasis. Gravitational unloading treatment induced a decrease in mitochondrial proteins, mainly affecting efficiency of the respiratory chain. Metabolomic analysis revealed that microgravity influenced several metabolic pathways; stimulating glycolysis and the pentose phosphate pathways, while the Krebs cycle was interrupted at succinate-fumarate transformation. Interestingly, proteomic analysis revealed that Complex II of the mitochondrial respiratory chain, which catalyses the biotransformation of this step, was under-represented by 50%. Accordingly, down-regulation of quinones 9 and 10 was measured. Complex III resulted in up-regulation by 60%, while Complex IV was down-regulated by 14%, accompanied by a reduction in proton transport synthesis of ATP. Finally, microgravity treatment induced an oxidative stress response, indicated by significant decreases in oxidised glutathione and antioxidant enzymes. Decrease in malate dehydrogenase induced a reverse in the malate-aspartate shuttle, contributing to dysregulation of ATP synthesis. Beta-oxidation of fatty acids was inhibited, promoting triglyceride production along with a reduction in the glycerol shuttle. Taken together, our findings suggest that microgravity may suppress bone cell functions, impairing mitochondrial energy potential and the energy state of the cell.
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Affiliation(s)
- Anna Michaletti
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Magda Gioia
- Department of Clinical Medicine and Translational Science, University of Rome Tor Vergata, Rome, Italy
| | - Umberto Tarantino
- Department of Clinical Medicine and Translational Science, University of Rome Tor Vergata, Rome, Italy
| | - Lello Zolla
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy.
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34
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Miller MS, Callahan DM, Tourville TW, Slauterbeck JR, Kaplan A, Fiske BR, Savage PD, Ades PA, Beynnon BD, Toth MJ. Moderate-intensity resistance exercise alters skeletal muscle molecular and cellular structure and function in inactive older adults with knee osteoarthritis. J Appl Physiol (1985) 2017; 122:775-787. [PMID: 28082334 DOI: 10.1152/japplphysiol.00830.2016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/27/2016] [Accepted: 01/09/2017] [Indexed: 12/25/2022] Open
Abstract
High-intensity resistance exercise (REX) training increases physical capacity, in part, by improving muscle cell size and function. Moderate-intensity REX, which is more feasible for many older adults with disease and/or disability, also increases physical function, but the mechanisms underlying such improvements are not understood. Therefore, we measured skeletal muscle structure and function from the molecular to the tissue level in response to 14 wk of moderate-intensity REX in physically inactive older adults with knee osteoarthritis (n = 17; 70 ± 1 yr). Although REX training increased quadriceps muscle cross-sectional area (CSA), average single-fiber CSA was unchanged because of reciprocal changes in myosin heavy chain (MHC) I and IIA fibers. Intermyofibrillar mitochondrial content increased with training because of increases in mitochondrial size in men, but not women, with no changes in subsarcolemmal mitochondria in either sex. REX increased whole muscle contractile performance similarly in men and women. In contrast, adaptations in single-muscle fiber force production per CSA (i.e., tension) and contractile velocity varied between men and women in a fiber type-dependent manner, with adaptations being explained at the molecular level by differential changes in myosin-actin cross-bridge kinetics and mechanics and single-fiber MHC protein expression. Our results are notable compared with studies of high-intensity REX because they show that the effects of moderate-intensity REX in older adults on muscle fiber size/structure and myofilament function are absent or modest. Moreover, our data highlight unique sex-specific adaptations due to differential cellular and subcellular structural and functional changes.NEW & NOTEWORTHY Moderate-intensity resistance training causes sex-specific adaptations in skeletal muscle structure and function at the cellular and molecular levels in inactive older adult men and women with knee osteoarthritis. However, these responses were minimal compared with high-intensity resistance training. Thus adjuncts to moderate-intensity training need to be developed to correct underlying cellular and molecular structural and functional deficits that are at the root of impaired physical function in this mobility-limited population.
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Affiliation(s)
- Mark S Miller
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont.,Department of Kinesiology, University of Massachusetts, Amherst, Massachusetts
| | | | - Timothy W Tourville
- Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, Vermont.,Department of Rehabilitation and Movement Science, University of Vermont, Burlington, Vermont; and
| | - James R Slauterbeck
- Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, Vermont
| | - Anna Kaplan
- Department of Medicine, University of Vermont, Burlington, Vermont
| | - Brad R Fiske
- Department of Medicine, University of Vermont, Burlington, Vermont
| | - Patrick D Savage
- Department of Medicine, University of Vermont, Burlington, Vermont
| | - Philip A Ades
- Department of Medicine, University of Vermont, Burlington, Vermont
| | - Bruce D Beynnon
- Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, Vermont
| | - Michael J Toth
- Department of Medicine, University of Vermont, Burlington, Vermont.,Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont.,Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, Vermont
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Cheng LH, Hung KF, Lee TC, Huang CY, Chiu WT, Lo JF, Huang TF. Mitochondrial co-chaperone protein Tid1 is required for energy homeostasis during skeletal myogenesis. Stem Cell Res Ther 2016; 7:185. [PMID: 27927223 PMCID: PMC5143475 DOI: 10.1186/s13287-016-0443-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 11/01/2016] [Accepted: 11/17/2016] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Tid1 is a mitochondrial co-chaperone protein and its transcript is abundantly expressed in skeletal muscle tissues. However, the physiological function of Tid1 during skeletal myogenesis remains unclear. METHODS In vitro induced differentiation assay of mouse myoblast C2C12 cells was applied to examine the physiological role of Tid1 during skeletal myogenesis. In addition, transgenic mice with muscle specific (HSA-Cre) Tid1 deletion were established and examined to determine the physiological function of Tid1 during skeletal muscle development in vivo. RESULTS Expression of Tid1 protein was upregulated in the differentiated C2C12 cells, and the HSA-Tid1f/f mice displayed muscular dystrophic phenotype. The expression of myosin heavy chain (MyHC), the protein served as the muscular development marker, was reduced in HSA-Tid1f/f mice at postnatal day (P)5 and P8. The protein levels of ATP sensor (p-AMPK) and mitochondrial biogenesis protein (PGC-1α) were also significantly reduced in HSA-Tid1f/f mice. Moreover, Tid1 deficiency induced apoptotic marker Caspase-3 in muscle tissues of HSA-Tid1f/f mice. Consistent with the in vivo finding, we observed that downregulation of Tid1 not only reduced the ATP production but also abolished the differentiation ability of C2C12 cells by impairing the mitochondrial activity. CONCLUSION Together, our results suggest that Tid1 deficiency reduces ATP production and abolishes mitochondrial activity, resulting in energy imbalance and promoting apoptosis of muscle cells during myogenesis. It will be of importance to understand the function of Tid1 during human muscular dystrophy in the future.
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Affiliation(s)
- Li-Hao Cheng
- Institute of Oral Biology, National Yang-Ming University, Taipei, Taiwan, Republic of China
| | - Kai-Feng Hung
- Department of Dentistry, School of Dentistry, National Yang-Ming University, Taipei, Taiwan, Republic of China
| | - Te-Chang Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Chih-Yang Huang
- Graduate Institute of Chinese Medical Science and Institute of Medical Science, China Medical University, Taichung, Taiwan, Republic of China.,Institute of Basic Medical Science, China Medical University, Taichung, Taiwan, Republic of China.,Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan, Republic of China
| | - Wen-Ting Chiu
- Institute of Oral Biology, National Yang-Ming University, Taipei, Taiwan, Republic of China
| | - Jeng-Fan Lo
- Institute of Oral Biology, National Yang-Ming University, Taipei, Taiwan, Republic of China. .,Department of Dentistry, School of Dentistry, National Yang-Ming University, Taipei, Taiwan, Republic of China. .,Graduate Institute of Chinese Medical Science and Institute of Medical Science, China Medical University, Taichung, Taiwan, Republic of China. .,Department of Dentistry, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China. .,Genome Research Center, National Yang-Ming University, Taipei, Taiwan, Republic of China. .,National Yang-Ming University VGH Genome Research Center, Taipei, Taiwan, Republic of China.
| | - Tung-Fu Huang
- School of Medicine, National Yang-Ming University, Taipei, Taiwan, Republic of China. .,Department of Orthopedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China.
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36
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Wawrzyniak NR, Joseph AM, Levin DG, Gundermann DM, Leeuwenburgh C, Sandesara B, Manini TM, Adhihetty PJ. Idiopathic chronic fatigue in older adults is linked to impaired mitochondrial content and biogenesis signaling in skeletal muscle. Oncotarget 2016; 7:52695-52709. [PMID: 27447862 PMCID: PMC5288142 DOI: 10.18632/oncotarget.10685] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 06/09/2016] [Indexed: 12/22/2022] Open
Abstract
Fatigue is a symptom of many diseases, but it can also manifest as a unique medical condition, such as idiopathic chronic fatigue (ICF). While the prevalence of ICF increases with age, mitochondrial content and function decline with age, which may contribute to ICF. The purpose of this study was to determine whether skeletal muscle mitochondrial dysregulation and oxidative stress is linked to ICF in older adults. Sedentary, old adults (n = 48, age 72.4 ± 5.3 years) were categorized into ICF and non-fatigued (NF) groups based on the FACIT-Fatigue questionnaire. ICF individuals had a FACIT score one standard deviation below the mean for non-anemic adults > 65 years and were excluded according to CDC diagnostic criteria for ICF. Vastus lateralis muscle biopsies were analyzed, showing reductions in mitochondrial content and suppression of mitochondrial regulatory proteins Sirt3, PGC-1α, NRF-1, and cytochrome c in ICF compared to NF. Additionally, mitochondrial morphology proteins, antioxidant enzymes, and lipid peroxidation were unchanged in ICF individuals. Our data suggests older adults with ICF have reduced skeletal muscle mitochondrial content and biogenesis signaling that cannot be accounted for by increased oxidative damage.
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Affiliation(s)
- Nicholas R. Wawrzyniak
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Anna-Maria Joseph
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, Florida, USA
| | - David G. Levin
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - David M. Gundermann
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, Florida, USA
| | - Christiaan Leeuwenburgh
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, Florida, USA
| | - Bhanuprasad Sandesara
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, Florida, USA
| | - Todd M. Manini
- Department of Aging and Geriatric Research, Division of Biology of Aging, University of Florida, Gainesville, Florida, USA
| | - Peter J. Adhihetty
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
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Lau J, Goh CC, Devi S, Keeble J, See P, Ginhoux F, Ng LG. Intravital multiphoton imaging of mouse tibialis anterior muscle. INTRAVITAL 2016; 5:e1156272. [PMID: 28243520 PMCID: PMC5226003 DOI: 10.1080/21659087.2016.1156272] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 02/11/2016] [Accepted: 02/15/2016] [Indexed: 01/03/2023]
Abstract
Intravital imaging by multiphoton microscopy is a powerful tool to gain invaluable insight into tissue biology and function. Here, we provide a step-by-step tissue preparation protocol for imaging the mouse tibialis anterior skeletal muscle. Additionally, we include steps for jugular vein catheterization that allow for well-controlled intravenous reagent delivery. Preparation of the tibialis anterior muscle is minimally invasive, reducing the chances of inducing damage and inflammation prior to imaging. The tibialis anterior muscle is useful for imaging leukocyte interaction with vascular endothelium, and to understand muscle contraction biology. Importantly, this model can be easily adapted to study neuromuscular diseases and myopathies.
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Affiliation(s)
- Jasmine Lau
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , Biopolis, Singapore
| | - Chi Ching Goh
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , Biopolis, Singapore
| | - Sapna Devi
- Department of Microbiology and Immunology, The Peter Doherty Institute, The University of Melbourne , Parkville, Victoria, Australia
| | - Jo Keeble
- Department of Medicine, University of Melbourne, Department of Rheumatology, Royal Melbourne Hospital, Inflammation Division, Walter and Eliza Hall Institute of Medical Research , Melbourne, Australia
| | - Peter See
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , Biopolis, Singapore
| | - Florent Ginhoux
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , Biopolis, Singapore
| | - Lai Guan Ng
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR) , Biopolis, Singapore
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38
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Mitochondria in White, Brown, and Beige Adipocytes. Stem Cells Int 2016; 2016:6067349. [PMID: 27073398 PMCID: PMC4814709 DOI: 10.1155/2016/6067349] [Citation(s) in RCA: 147] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 01/17/2016] [Accepted: 01/28/2016] [Indexed: 12/18/2022] Open
Abstract
Mitochondria play a key role in energy metabolism in many tissues, including cardiac and skeletal muscle, brain, liver, and adipose tissue. Three types of adipose depots can be identified in mammals, commonly classified according to their colour appearance: the white (WAT), the brown (BAT), and the beige/brite/brown-like (bAT) adipose tissues. WAT is mainly involved in the storage and mobilization of energy and BAT is predominantly responsible for nonshivering thermogenesis. Recent data suggest that adipocyte mitochondria might play an important role in the development of obesity through defects in mitochondrial lipogenesis and lipolysis, regulation of adipocyte differentiation, apoptosis, production of oxygen radicals, efficiency of oxidative phosphorylation, and regulation of conversion of white adipocytes into brown-like adipocytes. This review summarizes the main characteristics of each adipose tissue subtype and describes morphological and functional modifications focusing on mitochondria and their activity in healthy and unhealthy adipocytes.
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Park SY, Rossman MJ, Gifford JR, Bharath LP, Bauersachs J, Richardson RS, Abel ED, Symons JD, Riehle C. Exercise training improves vascular mitochondrial function. Am J Physiol Heart Circ Physiol 2016; 310:H821-9. [PMID: 26825520 DOI: 10.1152/ajpheart.00751.2015] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/25/2016] [Indexed: 12/17/2022]
Abstract
Exercise training is recognized to improve cardiac and skeletal muscle mitochondrial respiratory capacity; however, the impact of chronic exercise on vascular mitochondrial respiratory function is unknown. We hypothesized that exercise training concomitantly increases both vascular mitochondrial respiratory capacity and vascular function. Arteries from both sedentary (SED) and swim-trained (EX, 5 wk) mice were compared in terms of mitochondrial respiratory function, mitochondrial content, markers of mitochondrial biogenesis, redox balance, nitric oxide (NO) signaling, and vessel function. Mitochondrial complex I and complex I + II state 3 respiration and the respiratory control ratio (complex I + II state 3 respiration/complex I state 2 respiration) were greater in vessels from EX relative to SED mice, despite similar levels of arterial citrate synthase activity and mitochondrial DNA content. Furthermore, compared with the SED mice, arteries from EX mice displayed elevated transcript levels of peroxisome proliferative activated receptor-γ coactivator-1α and the downstream targets cytochrome c oxidase subunit IV isoform 1,isocitrate dehydrogenase(Idh)2, and Idh3a, increased manganese superoxide dismutase protein expression, increased endothelial NO synthase phosphorylation (Ser(1177)), and suppressed reactive oxygen species generation (all P< 0.05). Although there were no differences in EX and SED mice concerning endothelium-dependent and endothelium-independent vasorelaxation, phenylephrine-induced vasocontraction was blunted in vessels from EX compared with SED mice, and this effect was normalized by NOS inhibition. These training-induced increases in vascular mitochondrial respiratory capacity and evidence of improved redox balance, which may, at least in part, be attributable to elevated NO bioavailability, have the potential to protect against age- and disease-related challenges to arterial function.
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Affiliation(s)
- Song-Young Park
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Matthew J Rossman
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Leena P Bharath
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah; Division of Endocrinology, Metabolism and Diabetes, and Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah; and
| | - Johann Bauersachs
- Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - E Dale Abel
- Division of Endocrinology, Metabolism and Diabetes, and Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah; and Fraternal Order of Eagles Diabetes Research Center and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - J David Symons
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah; Division of Endocrinology, Metabolism and Diabetes, and Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah; and
| | - Christian Riehle
- Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany; Division of Endocrinology, Metabolism and Diabetes, and Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah; and Fraternal Order of Eagles Diabetes Research Center and Division of Endocrinology and Metabolism, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
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Christ ER, Egger A, Allemann S, Buehler T, Kreis R, Boesch C. Effects of aerobic exercise on ectopic lipids in patients with growth hormone deficiency before and after growth hormone replacement therapy. Sci Rep 2016; 6:19310. [PMID: 26792091 PMCID: PMC4726290 DOI: 10.1038/srep19310] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 12/09/2015] [Indexed: 01/21/2023] Open
Abstract
Growth hormone replacement therapy (GHRT) increases exercise capacity and insulin resistance while it decreases fat mass in growth hormone-deficient patients (GHD). Ectopic lipids (intramyocellular (IMCL) and intrahepatocellular lipids (IHCL) are related to insulin resistance. The effect of GHRT on ectopic lipids is unknown. It is hypothesized that exercise-induced utilization of ectopic lipids is significantly decreased in GHD patients and normalized by GHRT. GHD (4 females, 6 males) and age/gender/waist-matched control subjects (CS) were studied. VO2max was assessed on a treadmill and insulin sensitivity determined by a two-step hyperinsulinaemic-euglycaemic clamp. Visceral (VAT) and subcutaneous (SAT) fat were quantified by MR-imaging. IHCL and IMCL were measured before and after a 2 h exercise at 50-60% of VO2max using MR-spectroscopy (∆IMCL, ∆IHCL). Identical investigations were performed after 6 months of GHRT. VO2max was similar in GHD and CS and significantly increased after GHRT; GHRT significantly decreased SAT and VAT. 2 h-exercise resulted in a decrease in IMCL (significant in CS and GHRT) and a significant increase in IHCL in CS and GHD pre and post GHRT. GHRT didn't significantly impact on ∆IMCL and ∆IHCL. We conclude that aerobic exercise affects ectopic lipids in patients and controls. GHRT increases exercise capacity without influencing ectopic lipids.
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Affiliation(s)
- Emanuel R Christ
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, CH-3010 Bern, Switzerland
| | - Andrea Egger
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, CH-3010 Bern, Switzerland.,Department of Internal Medicine, University Hospital of Basel, CH-4056 Basel, Switzerland
| | - Sabin Allemann
- Division of Endocrinology, Diabetology and Clinical Nutrition, University Hospital of Bern, Inselspital, CH-3010 Bern, Switzerland
| | - Tania Buehler
- Department of Clinical Research, Division of MR-Spectroscopy and Methodology, University of Bern, Inselspital, CH-3010 Bern, Switzerland
| | - Roland Kreis
- Department of Clinical Research, Division of MR-Spectroscopy and Methodology, University of Bern, Inselspital, CH-3010 Bern, Switzerland
| | - Chris Boesch
- Department of Clinical Research, Division of MR-Spectroscopy and Methodology, University of Bern, Inselspital, CH-3010 Bern, Switzerland
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Obesity-Related Diseases and Syndromes: Insulin Resistance, Type 2 Diabetes Mellitus, Non-alcoholic Fatty Liver Disease, Cardiovascular Disease, and Metabolic Syndrome. Obesity (Silver Spring) 2016. [DOI: 10.1007/978-3-319-39409-1_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Kim Y, Kim D, Good DJ, Park Y. Effects of postweaning administration of conjugated linoleic acid on development of obesity in nescient basic helix-loop-helix 2 knockout mice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:5212-5223. [PMID: 25976059 DOI: 10.1021/acs.jafc.5b00840] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Conjugated linoleic acid (CLA) has been reported to prevent body weight gain and fat accumulation in part by improving physical activity in mice. However, the effects of postweaning administration of CLA on the development of obesity later in life have not yet been demonstrated. The current study investigated the role of postweaning CLA treatment on skeletal muscle energy metabolism in genetically induced inactive adult-onset obese model, nescient basic helix-loop-helix 2 knockout (N2KO) mice. Four-week-old male N2KO and wild type mice were fed either control or a CLA-containing diet (0.5%) for 4 weeks, and then CLA was withdrawn and control diet provided to all mice for the following 8 weeks. Postweaning CLA supplementation in wild type animals, but not N2KO mice, may activate AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor-δ (PPARδ) as well as promote desensitization of phosphatase and tensin homologue (PTEN) and sensitization of protein kinase B (AKT) at threonine 308 in gastrocnemius skeletal muscle, improving voluntary activity and glucose homeostasis. We suggest that postweaning administration of CLA may in part stimulate the underlying molecular targets involved in muscle energy metabolism to reduce weight gain in normal animals, but not in the genetically induced inactive adult-onset animal model.
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Affiliation(s)
| | | | - Deborah J Good
- §Department of Human Nutrition, Foods and Exercise, Virginia Tech, Blacksburg, Virginia 24061, United States
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Lee I, Hüttemann M, Kruger A, Bollig-Fischer A, Malek MH. (-)-Epicatechin combined with 8 weeks of treadmill exercise is associated with increased angiogenic and mitochondrial signaling in mice. Front Pharmacol 2015; 6:43. [PMID: 25821434 PMCID: PMC4358069 DOI: 10.3389/fphar.2015.00043] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 02/18/2015] [Indexed: 11/13/2022] Open
Abstract
The purpose of this study was to conduct an 8 week endurance training program with and without (–)–epicatechin treatment and to determine whether there is a possible cumulative effect on protein markers of angiogenesis and mitochondrial biogenesis. Thirty-four 14-month old male mice (C57BL/6N) were randomized into four groups: control (C); (–)–epicatechin only ((–)–Epi); control with endurance training (CE); and (–)–epicatechin with endurance training ((–)–Epi-Ex). Mice in the training groups performed treadmill exercise for 8 weeks (5 × /week for 60 min/session), whereas mice in the (–)–epicatechin group received 1.0 mg/kg of body mass twice daily during the training period. At 8 weeks, distance ran on the treadmill increased by 46, 69, and 84% in the (–)–Epi, CE, and (–)–Epi-Ex groups, respectively compared to the control group (p < 0.001 for all comparisons). Furthermore, the (–)–Epi-Ex group had significantly higher exercise capacity than the (–)–Epi and CE group. For angiogenic regulators, the (–)–Epi-Ex group had significantly higher VEGF-R2 protein expression with a concomitant reduction in TSP-1 protein expression than the exercise group. Interestingly, FoxO1 protein expression was significantly reduced for all three experimental groups compared to the control group. Protein markers such as PGC-1β and TFAM were significantly higher in the (–)–Epi-Ex group compared to the three other groups. These findings suggest that (–)–epicatechin treatment combined with 8 weeks of endurance training provide a cumulative effect on a number of angiogenic and mitochondrial signaling which functionally translates to enhanced exercise tolerance.
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Affiliation(s)
- Icksoo Lee
- College of Medicine, Dankook University , Cheonan-si, South Korea
| | - Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine , Detroit, MI, USA ; Cardiovascular Research Institute, Wayne State University School of Medicine , Detroit, MI, USA
| | - Adele Kruger
- Department of Obstetrics and Gynecology, Wayne State University , Detroit, MI, USA
| | | | - Moh H Malek
- Cardiovascular Research Institute, Wayne State University School of Medicine , Detroit, MI, USA ; Integrative Physiology of Exercise Laboratory, Department of Health Care Sciences, Wayne State University Eugene Applebaum College of Pharmacy and Health Sciences , Detroit, MI, USA
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Crescenzo R, Bianco F, Mazzoli A, Giacco A, Liverini G, Iossa S. Mitochondrial efficiency and insulin resistance. Front Physiol 2015; 5:512. [PMID: 25601841 PMCID: PMC4283517 DOI: 10.3389/fphys.2014.00512] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/09/2014] [Indexed: 01/02/2023] Open
Abstract
Insulin resistance, “a relative impairment in the ability of insulin to exert its effects on glucose, protein and lipid metabolism in target tissues,” has many detrimental effects on metabolism and is strongly correlated to deposition of lipids in non-adipose tissues. Mitochondria are the main cellular sites devoted to ATP production and fatty acid oxidation. Therefore, a role for mitochondrial dysfunction in the onset of skeletal muscle insulin resistance has been proposed and many studies have dealt with possible alteration in mitochondrial function in obesity and diabetes, both in humans and animal models. Data reporting evidence of mitochondrial dysfunction in type two diabetes mellitus are numerous, even though the issue that this reduced mitochondrial function is causal in the development of the disease is not yet solved, also because a variety of parameters have been used in the studies carried out on this subject. By assessing the alterations in mitochondrial efficiency as well as the impact of this parameter on metabolic homeostasis of skeletal muscle cells, we have obtained results that allow us to suggest that an increase in mitochondrial efficiency precedes and therefore can contribute to the development of high-fat-induced insulin resistance in skeletal muscle.
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Affiliation(s)
| | - Francesca Bianco
- Department of Biology, University of Naples "Federico II" Napoli, Italy
| | - Arianna Mazzoli
- Department of Biology, University of Naples "Federico II" Napoli, Italy
| | - Antonia Giacco
- Department of Biology, University of Naples "Federico II" Napoli, Italy
| | - Giovanna Liverini
- Department of Biology, University of Naples "Federico II" Napoli, Italy
| | - Susanna Iossa
- Department of Biology, University of Naples "Federico II" Napoli, Italy
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45
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Ferretti G. Maximal oxygen consumption in healthy humans: theories and facts. Eur J Appl Physiol 2014; 114:2007-36. [PMID: 24986693 DOI: 10.1007/s00421-014-2911-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 05/12/2014] [Indexed: 12/17/2022]
Abstract
This article reviews the concept of maximal oxygen consumption ([Formula: see text]) from the perspective of multifactorial models of [Formula: see text] limitation. First, I discuss procedural aspects of [Formula: see text] measurement: the implications of ramp protocols are analysed within the theoretical work of Morton. Then I analyse the descriptive physiology of [Formula: see text], evidencing the path that led to the view of monofactorial cardiovascular or muscular [Formula: see text] limitation. Multifactorial models, generated by the theoretical work of di Prampero and Wagner around the oxygen conductance equation, represented a radical change of perspective. These models are presented in detail and criticized with respect to the ensuing experimental work. A synthesis between them is proposed, demonstrating how much these models coincide and converge on the same conclusions. Finally, I discuss the cases of hypoxia and bed rest, the former as an example of the pervasive effects of the shape of the oxygen equilibrium curve, the latter as a neat example of adaptive changes concerning the entire respiratory system. The conclusion is that the concept of cardiovascular [Formula: see text] limitation is reinforced by multifactorial models, since cardiovascular oxygen transport provides most of the [Formula: see text] limitation, at least in normoxia. However, the same models show that the role of peripheral resistances is significant and cannot be neglected. The role of peripheral factors is greater the smaller is the active muscle mass. In hypoxia, the intervention of lung resistances as limiting factors restricts the role played by cardiovascular and peripheral factors.
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Affiliation(s)
- Guido Ferretti
- Département des Neurosciences Fondamentales, Université de Genève, 1 Rue Michel Servet, 1211, Geneva 4, Switzerland,
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Murray AJ. Mitochondria at the extremes: pioneers, protectorates, protagonists. EXTREME PHYSIOLOGY & MEDICINE 2014; 3:10. [PMID: 24822089 PMCID: PMC4017221 DOI: 10.1186/2046-7648-3-10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 04/28/2014] [Indexed: 11/10/2022]
Abstract
The engulfment of a proto-mitochondrion by a primitive unicellular organism gave rise to the first eukaryotic cell, and ever since, mitochondrial function has been a vital aspect of eukaryotic life. Under conditions of physiological stress, the mitochondrion is far from a passive bystander, instead playing a key role in signalling pathways and the cellular responses they elicit. In this thematic series of Extreme Physiology & Medicine, the role of the mitochondrion in the response to physiological stress will be considered anew, through research articles, reviews, viewpoints and methodology papers that aim to reposition the organelle as a key player in the human response to a wide range of extreme conditions.
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Affiliation(s)
- Andrew J Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
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Bucher J, Krüsi M, Zueger T, Ith M, Stettler C, Diem P, Boesch C, Kreis R, Christ E. The effect of a single 2 h bout of aerobic exercise on ectopic lipids in skeletal muscle, liver and the myocardium. Diabetologia 2014; 57:1001-5. [PMID: 24563325 DOI: 10.1007/s00125-014-3193-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 01/28/2014] [Indexed: 11/26/2022]
Abstract
AIMS/HYPOTHESIS Ectopic lipids are fuel stores in non-adipose tissues (skeletal muscle [intramyocellular lipids; IMCL], liver [intrahepatocellular lipids; IHCL] and heart [intracardiomyocellular lipids; ICCL]). IMCL can be depleted by physical activity. Preliminary data suggest that aerobic exercise increases IHCL. Data on exercise-induced changes on ICCL is scarce. Increased IMCL and IHCL have been related to insulin resistance in skeletal muscles and liver, whereas this has not been documented in the heart. The aim of this study was to assess the acute effect of aerobic exercise on the flexibility of IMCL, IHCL and ICCL in insulin-sensitive participants in relation to fat availability, insulin sensitivity and exercise capacity. METHODS Healthy physically active men were included. VO(2max) was assessed by spiroergometry and insulin sensitivity was calculated using the HOMA index. Visceral and subcutaneous fat were separately quantified by MRI. Following a standardised dietary fat load over 3 days, IMCL, IHCL and ICCL were measured using MR spectroscopy before and after a 2 h exercise session at 50-60% of VO(2max). Metabolites were measured during exercise. RESULTS Ten men (age 28.9 ± 6.4 years, mean ± SD; VO(2max) 56.3 ± 6.4 ml kg(-1) min(-1); BMI 22.75 ± 1.4 kg/m(2)) were recruited. A 2 h exercise session resulted in a significant decrease in IMCL (-17 ± 22%, p = 0.008) and ICCL (-17 ± 14%, p = 0.002) and increase in IHCL (42 ± 29%, p = 0.004). No significant correlations were found between the relative changes in ectopic lipids, fat availability, insulin sensitivity, exercise capacity or changes of metabolites during exercise. CONCLUSIONS/INTERPRETATION In this group, physical exercise decreased ICCL and IMCL but increased IHCL. Fat availability, insulin sensitivity, exercise capacity and metabolites during exercise are not the only factors affecting ectopic lipids during exercise.
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Affiliation(s)
- Julie Bucher
- Department of Endocrinology, Diabetology and Clinical Nutrition, Inselspital, University Hospital of Bern, Freiburgstrasse, 3010, Bern, Switzerland
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Mills DE, Johnson MA, McPhilimey MJ, Williams NC, Gonzalez JT, Barnett YA, Sharpe GR. Influence of oxidative stress, diaphragm fatigue, and inspiratory muscle training on the plasma cytokine response to maximum sustainable voluntary ventilation. J Appl Physiol (1985) 2014; 116:970-9. [DOI: 10.1152/japplphysiol.01271.2013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The influence of oxidative stress, diaphragm fatigue, and inspiratory muscle training (IMT) on the cytokine response to maximum sustainable voluntary ventilation (MSVV) is unknown. Twelve healthy males were divided equally into an IMT or placebo (PLA) group, and before and after a 6-wk intervention they undertook, on separate days, 1 h of ( 1) passive rest and ( 2) MSVV, whereby participants undertook volitional hyperpnea at rest that mimicked the breathing and respiratory muscle recruitment patterns commensurate with heavy cycling exercise. Plasma cytokines remained unchanged during passive rest. There was a main effect of time ( P < 0.01) for plasma interleukin-1β (IL-1β) and interleukin-6 (IL-6) concentrations and a strong trend ( P = 0.067) for plasma interleukin-1 receptor antagonist concentration during MSVV. Plasma IL-6 concentration was reduced after IMT by 27 ± 18% (main effect of intervention, P = 0.029), whereas there was no change after PLA ( P = 0.753). There was no increase in a systemic marker of oxidative stress [DNA damage in peripheral blood mononuclear cells (PBMC)], and diaphragm fatigue was not related to the increases in plasma IL-1β and IL-6 concentrations. A dose-response relationship was observed between respiratory muscle work and minute ventilation and increases in plasma IL-6 concentration. In conclusion, increases in plasma IL-1β and IL-6 concentrations during MSVV were not due to diaphragm fatigue or DNA damage in PBMC. Increases in plasma IL-6 concentration during MSVV are attenuated following IMT, and the plasma IL-6 response is dependent upon the level of respiratory muscle work and minute ventilation.
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Affiliation(s)
- Dean E. Mills
- Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; and
| | - Michael A. Johnson
- Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; and
| | - Martin J. McPhilimey
- Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; and
| | - Neil C. Williams
- Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; and
| | - Javier T. Gonzalez
- School of Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Yvonne A. Barnett
- Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; and
| | - Graham R. Sharpe
- Sport, Health and Performance Enhancement (SHAPE) Research Group, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom; and
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Alvehus M, Boman N, Söderlund K, Svensson MB, Burén J. Metabolic adaptations in skeletal muscle, adipose tissue, and whole-body oxidative capacity in response to resistance training. Eur J Appl Physiol 2014; 114:1463-71. [PMID: 24711079 DOI: 10.1007/s00421-014-2879-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 03/22/2014] [Indexed: 02/05/2023]
Abstract
PURPOSE The effects of resistance training on mitochondrial biogenesis and oxidative capacity in skeletal muscle are not fully characterized, and even less is known about alterations in adipose tissue. We aimed to investigate adaptations in oxidative metabolism in skeletal muscle and adipose tissue after 8 weeks of heavy resistance training in apparently healthy young men. METHODS Expression of genes linked to oxidative metabolism in the skeletal muscle and adipose tissue was assessed before and after the training program. Body composition, peak oxygen uptake (VO2 peak), fat oxidation, activity of mitochondrial enzyme in muscle, and serum adiponectin levels were also determined before and after resistance training. RESULTS In muscle, the expression of the genes AdipoR1 and COX4 increased after resistance training (9 and 13 %, respectively), whereas the expression levels of the genes PGC-1α, SIRT1, TFAM, CPT1b, and FNDC5 did not change. In adipose tissue, the expression of the genes SIRT1 and CPT1b decreased after training (20 and 23 %, respectively). There was an increase in lean mass (from 59.7 ± 6.1 to 61.9 ± 6.2 kg), VO2 peak (from 49.7 ± 5.5 to 56.3 ± 5.0 ml/kg/min), and fat oxidation (from 6.8 ± 2.1 to 9.1 ± 2.7 mg/kg fat-free mass/min) after training, whereas serum adiponectin levels decreased significantly and enzyme activity of citrate synthase and 3-hydroxyacyl-CoA dehydrogenase did not change. CONCLUSION Despite significant increases in VO2 peak, fat oxidation, and lean mass following resistance training, the total effect on gene expression and enzyme activity linked to oxidative metabolism was moderate.
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Affiliation(s)
- Malin Alvehus
- Department of Public Health and Clinical Medicine, Medicine, Umeå University, Umeå, Sweden,
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Bereiter-Hahn J. Do we age because we have mitochondria? PROTOPLASMA 2014; 251:3-23. [PMID: 23794102 DOI: 10.1007/s00709-013-0515-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 05/21/2013] [Indexed: 06/02/2023]
Abstract
The process of aging remains a great riddle. Production of reactive oxygen species (ROS) by mitochondria is an inevitable by-product of respiration, which has led to a hypothesis proposing the oxidative impairment of mitochondrial components (e.g., mtDNA, proteins, lipids) that initiates a vicious cycle of dysfunctional respiratory complexes producing more ROS, which again impairs function. This does not exclude other processes acting in parallel or targets for ROS action in other organelles than mitochondria. Given that aging is defined as the process leading to death, the role of mitochondria-based impairments in those organ systems responsible for human death (e.g., the cardiovascular system, cerebral dysfunction, and cancer) is described within the context of "garbage" accumulation and increasing insulin resistance, type 2 diabetes, and glycation of proteins. Mitochondrial mass, fusion, and fission are important factors in coping with impaired function. Both biogenesis of mitochondria and their degradation are important regulatory mechanisms stimulated by physical exercise and contribute to healthy aging. The hypothesis of mitochondria-related aging should be revised to account for the limitations of the degradative capacity of the lysosomal system. The processes involved in mitochondria-based impairments are very similar across a large range of organisms. Therefore, studies on model organisms from yeast, fungi, nematodes, flies to vertebrates, and from cells to organisms also add considerably to the understanding of human aging.
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Affiliation(s)
- Jürgen Bereiter-Hahn
- Institut für Zellbiologie und Neurowissenschaften, Goethe Universität Frankfurt am Main, Max-von-Lauestrasse 13, 60438, Frankfurt am Main, Germany,
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