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Ballesteros-Reviriego G, Arbillaga-Etxarri A, Martí JD. Inspiratory Muscle Training: Back to Basics Must be the First Step? Arch Bronconeumol 2024; 60:267-268. [PMID: 38702139 DOI: 10.1016/j.arbres.2024.03.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/23/2024] [Accepted: 03/25/2024] [Indexed: 05/06/2024]
Affiliation(s)
- Gonzalo Ballesteros-Reviriego
- Physiotherapy and Occupational Therapy Unit, Rehabilitation Department, Vall d'Hebron Hospital Universitari, Barcelona, Spain.
| | - Ane Arbillaga-Etxarri
- Deusto Physical TherapIker, Physical Therapy Department, Faculty of Health Sciences, University of Deusto, Donostia-San Sebastián, Spain
| | - Joan-Daniel Martí
- Physical Medicine and Rehabilitation Service, Clinic University Hospital, Barcelona, Spain
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Mitochondrial Ribosome Dysfunction in Human Alveolar Type II Cells in Emphysema. Biomedicines 2022; 10:biomedicines10071497. [PMID: 35884802 PMCID: PMC9313339 DOI: 10.3390/biomedicines10071497] [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: 11/10/2021] [Revised: 04/17/2022] [Accepted: 04/26/2022] [Indexed: 11/16/2022] Open
Abstract
Pulmonary emphysema is characterized by airspace enlargement and the destruction of alveoli. Alveolar type II (ATII) cells are very abundant in mitochondria. OXPHOS complexes are composed of proteins encoded by the mitochondrial and nuclear genomes. Mitochondrial 12S and 16S rRNAs are required to assemble the small and large subunits of the mitoribosome, respectively. We aimed to determine the mechanism of mitoribosome dysfunction in ATII cells in emphysema. ATII cells were isolated from control nonsmokers and smokers, and emphysema patients. Mitochondrial transcription and translation were analyzed. We also determined the miRNA expression. Decreases in ND1 and UQCRC2 expression levels were found in ATII cells in emphysema. Moreover, nuclear NDUFS1 and SDHB levels increased, and mitochondrial transcribed ND1 protein expression decreased. These results suggest an impairment of the nuclear and mitochondrial stoichiometry in this disease. We also detected low levels of the mitoribosome structural protein MRPL48 in ATII cells in emphysema. Decreased 16S rRNA expression and increased 12S rRNA levels were observed. Moreover, we analyzed miR4485-3p levels in this disease. Our results suggest a negative feedback loop between miR-4485-3p and 16S rRNA. The obtained results provide molecular mechanisms of mitoribosome dysfunction in ATII cells in emphysema.
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Alfahad AJ, Alzaydi MM, Aldossary AM, Alshehri AA, Almughem FA, Zaidan NM, Tawfik EA. Current views in chronic obstructive pulmonary disease pathogenesis and management. Saudi Pharm J 2022; 29:1361-1373. [PMID: 35002373 PMCID: PMC8720819 DOI: 10.1016/j.jsps.2021.10.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 10/22/2021] [Indexed: 01/11/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a progressive lung dysfunction caused mainly by inhaling toxic particles and cigarette smoking (CS). The continuous exposure to ruinous molecules can lead to abnormal inflammatory responses, permanent damages to the respiratory system, and irreversible pathological changes. Other factors, such as genetics and aging, influence the development of COPD. In the last decade, accumulating evidence suggested that mitochondrial alteration, including mitochondrial DNA damage, increased mitochondrial reactive oxygen species (ROS), abnormal autophagy, and apoptosis, have been implicated in the pathogenesis of COPD. The alteration can also extend to epigenetics, namely DNA methylation, histone modification, and non-coding RNA. This review will discuss the recent progressions in COPD pathology, pathophysiology, and molecular pathways. More focus will be shed on mitochondrial and epigenetic variations related to COPD development and the role of nanomedicine as a potential tool for the prevention and treatment of this disease.
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Affiliation(s)
- Ahmed J Alfahad
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
| | - Mai M Alzaydi
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
| | - Ahmad M Aldossary
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
| | - Abdullah A Alshehri
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
| | - Fahad A Almughem
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
| | - Nada M Zaidan
- Center of Excellence in Biomedicine, Joint Centers of Excellence Program, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
| | - Essam A Tawfik
- National Center of Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia.,Center of Excellence in Biomedicine, Joint Centers of Excellence Program, King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia
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4
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Diaphragm Morphology Assessed by Computed Tomography in Chronic Obstructive Pulmonary Disease. Ann Am Thorac Soc 2021; 18:955-962. [PMID: 33321048 DOI: 10.1513/annalsats.202007-865oc] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rationale: Chronic obstructive pulmonary disease (COPD) is associated with abnormal skeletal muscle morphology and function. Objectives: To test the hypothesis that in vivo diaphragm muscle morphology assessed by computed tomography (CT) imaging would be associated with COPD severity, exacerbations, health status, and exercise capacity. Methods: The COPD Morphometry Study is a cross-sectional study that enrolled a clinical sample of smokers with COPD. Spirometry was performed and COPD severity was defined according to guidelines. Three-dimensional left hemidiaphragm morphology was segmented from contiguous axial CT images acquired at maximal inspiration, yielding quantitative measures of diaphragm CT density in Hounsfield units, dome height, and muscle volume. Exacerbations prompting pharmacotherapy or hospitalization in the preceding 12 months and St. George's Respiratory Questionnaire for COPD were assessed. Incremental symptom-limited cycle ergometry quantified peak oxygen uptake ([Formula: see text]o2Peak). Associations were adjusted for age, sex, body height, body mass index, and smoking status. Results: Among 65 smokers with COPD (75% male; [mean ± standard deviation (SD)] 56 ± 26 pack-years; forced expiratory volume in 1 second [FEV1] percentage predicted 55 ± 23%), mean diaphragm CT density was 3.1 ± 10 Hounsfield units, dome height was 5.2 ± 1.3 cm, and muscle volume was 57 ± 24 cm3. A 1-SD decrement in the diaphragm CT density was associated with 8.3% lower FEV1, 3.27-fold higher odds of exacerbation history, 9.7-point higher score on the St. George's Respiratory Questionnaire for COPD, and 2.5 ml/kg/min lower [Formula: see text]o2Peak. A 1-SD decrement in dome height was associated with 11% lower FEV1 and 1.3 ml/kg/min lower [Formula: see text]o2Peak. There were no associations with diaphragm volume observed. Conclusions: CT-assessed diaphragm morphology was associated with COPD severity, exacerbations, impaired health status, and exercise intolerance. The mechanisms and functional impact of lower diaphragm CT density merit investigation.
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Zhang B, Li P, Li J, Liu X, Wu W. Effect of Oxidative Stress on Diaphragm Dysfunction and Exercise Intervention in Chronic Obstructive Pulmonary Disease. Front Physiol 2021; 12:684453. [PMID: 34163375 PMCID: PMC8215263 DOI: 10.3389/fphys.2021.684453] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 05/10/2021] [Indexed: 11/13/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) can cause extrapulmonary injury such as diaphragm dysfunction. Oxidative stress is one of the main factors causing diaphragm dysfunction in COPD. Exercise plays a positive role in the prevention and treatment of diaphragm dysfunction in COPD, and the changes in diaphragm structure and function induced by exercise are closely related to the regulation of oxidative stress. Therefore, on the basis of the review of oxidative stress and the changes in diaphragm structure and function in COPD, this article analyzed the effects of exercise on oxidative stress and diaphragm dysfunction in COPD and explored the possible mechanism by which exercise improves oxidative stress. Studies have found that diaphragm dysfunction in COPD includes the decline of muscle strength, endurance, and activity. Oxidative stress mainly affects the structure and function of the diaphragm in COPD through protein oxidation, protease activation and calcium sensitivity reduction. The effects of exercise on oxidative stress level and diaphragm dysfunction may differ depending on the intensity, duration, and style of exercise. The mechanism of exercise on oxidative stress in the diaphragm of COPD may include improving antioxidant capacity, reducing oxidase activity and improving mitochondrial function.
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Affiliation(s)
- Bingzhi Zhang
- Department of Sports Medicine, Shanghai University of Sport, Shanghai, China
| | - Peijun Li
- Department of Sports Medicine, Shanghai University of Sport, Shanghai, China
| | - Jian Li
- Department of Sports Medicine, Shanghai University of Sport, Shanghai, China
| | - Xiaodan Liu
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Weibing Wu
- Department of Sports Medicine, Shanghai University of Sport, Shanghai, China
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6
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Hahn D, Kumar RA, Ryan TE, Ferreira LF. Mitochondrial respiration and H 2O 2 emission in saponin-permeabilized murine diaphragm fibers: optimization of fiber separation and comparison to limb muscle. Am J Physiol Cell Physiol 2019; 317:C665-C673. [PMID: 31314583 DOI: 10.1152/ajpcell.00184.2019] [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: 01/20/2023]
Abstract
Diaphragm abnormalities in aging or chronic diseases include impaired mitochondrial respiration and H2O2 emission, which can be measured using saponin-permeabilized muscle fibers. Mouse diaphragm presents a challenge for isolation of fibers due to relatively high abundance of connective tissue in healthy muscle that is exacerbated in disease states. We tested a new approach to process mouse diaphragm for assessment of intact mitochondria respiration and ROS emission in saponin-permeabilized fibers. We used the red gastrocnemius (RG) as "standard" limb muscle. Markers of mitochondrial content were two- to fourfold higher in diaphragm (Dia) than in RG (P < 0.05). Maximal O2 consumption (JO2: pmol·s-1·mg-1) in Dia was higher with glutamate, malate, and succinate (Dia 399 ± 127, RG 148 ± 60; P < 0.05) and palmitoyl-CoA + carnitine (Dia 15 ± 5, RG 7 ± 1; P < 0.05) than in RG, but not different between muscles when JO2 was normalized to citrate synthase activity. Absolute JO2 for Dia was two- to fourfold higher than reported in previous studies. Mitochondrial JH2O2 was higher in Dia than in RG (P < 0.05), but lower in Dia than in RG when JH2O2 was normalized to citrate synthase activity. Our findings are consistent with an optimized diaphragm preparation for assessment of intact mitochondria in permeabilized fiber bundles. The data also suggest that higher mitochondrial content potentially makes the diaphragm more susceptible to "mitochondrial onset" myopathy. Overall, the new approach will facilitate testing and understanding of diaphragm mitochondrial function in mouse models that are used to advance biomedical research and human health.
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Affiliation(s)
- Dongwoo Hahn
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, Florida
| | - Ravi A Kumar
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, Florida
| | - Terence E Ryan
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, Florida
| | - Leonardo F Ferreira
- Department of Applied Physiology and Kinesiology, College of Health and Human Performance, University of Florida, Gainesville, Florida
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Laveneziana P, Albuquerque A, Aliverti A, Babb T, Barreiro E, Dres M, Dubé BP, Fauroux B, Gea J, Guenette JA, Hudson AL, Kabitz HJ, Laghi F, Langer D, Luo YM, Neder JA, O'Donnell D, Polkey MI, Rabinovich R, Rossi A, Series F, Similowski T, Spengler C, Vogiatzis I, Verges S. ERS statement on respiratory muscle testing at rest and during exercise. Eur Respir J 2019; 53:13993003.01214-2018. [DOI: 10.1183/13993003.01214-2018] [Citation(s) in RCA: 227] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 02/18/2019] [Indexed: 12/12/2022]
Abstract
Assessing respiratory mechanics and muscle function is critical for both clinical practice and research purposes. Several methodological developments over the past two decades have enhanced our understanding of respiratory muscle function and responses to interventions across the spectrum of health and disease. They are especially useful in diagnosing, phenotyping and assessing treatment efficacy in patients with respiratory symptoms and neuromuscular diseases. Considerable research has been undertaken over the past 17 years, since the publication of the previous American Thoracic Society (ATS)/European Respiratory Society (ERS) statement on respiratory muscle testing in 2002. Key advances have been made in the field of mechanics of breathing, respiratory muscle neurophysiology (electromyography, electroencephalography and transcranial magnetic stimulation) and on respiratory muscle imaging (ultrasound, optoelectronic plethysmography and structured light plethysmography). Accordingly, this ERS task force reviewed the field of respiratory muscle testing in health and disease, with particular reference to data obtained since the previous ATS/ERS statement. It summarises the most recent scientific and methodological developments regarding respiratory mechanics and respiratory muscle assessment by addressing the validity, precision, reproducibility, prognostic value and responsiveness to interventions of various methods. A particular emphasis is placed on assessment during exercise, which is a useful condition to stress the respiratory system.
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8
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Salazar-Degracia A, Busquets S, Argilés JM, López-Soriano FJ, Barreiro E. Formoterol attenuates increased oxidative stress and myosin protein loss in respiratory and limb muscles of cancer cachectic rats. PeerJ 2017; 5:e4109. [PMID: 29255650 PMCID: PMC5732544 DOI: 10.7717/peerj.4109] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 11/08/2017] [Indexed: 12/19/2022] Open
Abstract
Muscle mass loss and wasting are characteristic features of patients with chronic conditions including cancer. Therapeutic options are still scarce. We hypothesized that cachexia-induced muscle oxidative stress may be attenuated in response to treatment with beta2-adrenoceptor-selective agonist formoterol in rats. In diaphragm and gastrocnemius of tumor-bearing rats (108 AH-130 Yoshida ascites hepatoma cells inoculated intraperitoneally) with and without treatment with formoterol (0.3 mg/kg body weight/day for seven days, daily subcutaneous injection), redox balance (protein oxidation and nitration and antioxidants) and muscle proteins (1-dimensional immunoblots), carbonylated proteins (2-dimensional immunoblots), inflammatory cells (immunohistochemistry), and mitochondrial respiratory chain (MRC) complex activities were explored. In the gastrocnemius, but not the diaphragm, of cancer cachectic rats compared to the controls, protein oxidation and nitration levels were increased, several functional and structural proteins were carbonylated, and in both study muscles, myosin content was reduced, inflammatory cell counts were greater, while no significant differences were seen in MRC complex activities (I, II, and IV). Treatment of cachectic rats with formoterol attenuated all the events in both respiratory and limb muscles. In this in vivo model of cancer-cachectic rats, the diaphragm is more resistant to oxidative stress. Formoterol treatment attenuated the rise in oxidative stress in the limb muscles, inflammatory cell infiltration, and the loss of myosin content seen in both study muscles, whereas no effects were observed in the MRC complex activities. These findings have therapeutic implications as they demonstrate beneficial effects of the beta2 agonist through decreased protein oxidation and inflammation in cachectic muscles, especially the gastrocnemius.
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Affiliation(s)
- Anna Salazar-Degracia
- Pulmonology Department-Muscle Wasting and Cachexia in Chronic Respiratory Diseases and Lung Cancer Research Group, Health and Experimental Sciences Department (CEXS), IMIM-Hospital del Mar, Parc de Salut Mar, Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB), Barcelona, Spain
| | - Sílvia Busquets
- Cancer Research Group, Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Universitat de Barcelona, Barcelona, Spain.,Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain
| | - Josep M Argilés
- Cancer Research Group, Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Universitat de Barcelona, Barcelona, Spain.,Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain
| | - Francisco J López-Soriano
- Cancer Research Group, Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Universitat de Barcelona, Barcelona, Spain.,Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain
| | - Esther Barreiro
- Pulmonology Department-Muscle Wasting and Cachexia in Chronic Respiratory Diseases and Lung Cancer Research Group, Health and Experimental Sciences Department (CEXS), IMIM-Hospital del Mar, Parc de Salut Mar, Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB), Barcelona, Spain.,Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Barcelona, Spain
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9
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10
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LaRosa DA, Ellery SJ, Walker DW, Dickinson H. Understanding the Full Spectrum of Organ Injury Following Intrapartum Asphyxia. Front Pediatr 2017; 5:16. [PMID: 28261573 PMCID: PMC5313537 DOI: 10.3389/fped.2017.00016] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 01/23/2017] [Indexed: 11/13/2022] Open
Abstract
Birth asphyxia is a significant global health problem, responsible for ~1.2 million neonatal deaths each year worldwide. Those who survive often suffer from a range of health issues including brain damage-manifesting as cerebral palsy (CP)-respiratory insufficiency, cardiovascular collapse, and renal dysfunction, to name a few. Although the majority of research is directed toward reducing the brain injury that results from intrapartum birth asphyxia, the multi-organ injury observed in surviving neonates is of equal importance. Despite the advent of hypothermia therapy for the treatment of hypoxic-ischemic encephalopathy (HIE), treatment options following asphyxia at birth remain limited, particularly in low-resource settings where the incidence of birth asphyxia is highest. Furthermore, although cooling of the neonate results in improved neurological outcomes for a small proportion of treated infants, it does not provide any benefit to the other organ systems affected by asphyxia at birth. The aim of this review is to summarize the current knowledge of the multi-organ effects of intrapartum asphyxia, with particular reference to the findings from our laboratory using the precocial spiny mouse to model birth asphyxia. Furthermore, we reviewed the current treatments available for neonates who have undergone intrapartum asphyxia, and highlight the emergence of maternal dietary creatine supplementation as a preventative therapy, which has been shown to provide multi-organ protection from birth asphyxia-induced injury in our preclinical studies. This cheap and effective nutritional supplement may be the key to reducing birth asphyxia-induced death and disability, particularly in low-resource settings where current treatments are unavailable.
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Affiliation(s)
- Domenic A LaRosa
- Ritchie Centre, Department of Obstetrics and Gynaecology, Hudson Institute of Medical Research, Monash University, Melbourne, VIC, Australia; Department of Pediatrics, The Alpert Medical School of Brown University, Women & Infants Hospital of Rhode Island, Providence, RI, USA
| | - Stacey J Ellery
- Ritchie Centre, Department of Obstetrics and Gynaecology, Hudson Institute of Medical Research, Monash University , Melbourne, VIC , Australia
| | - David W Walker
- Ritchie Centre, Department of Obstetrics and Gynaecology, Hudson Institute of Medical Research, Monash University , Melbourne, VIC , Australia
| | - Hayley Dickinson
- Ritchie Centre, Department of Obstetrics and Gynaecology, Hudson Institute of Medical Research, Monash University , Melbourne, VIC , Australia
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Lewis P, O'Halloran KD. Diaphragm Muscle Adaptation to Sustained Hypoxia: Lessons from Animal Models with Relevance to High Altitude and Chronic Respiratory Diseases. Front Physiol 2016; 7:623. [PMID: 28018247 PMCID: PMC5149537 DOI: 10.3389/fphys.2016.00623] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 11/28/2016] [Indexed: 12/13/2022] Open
Abstract
The diaphragm is the primary inspiratory pump muscle of breathing. Notwithstanding its critical role in pulmonary ventilation, the diaphragm like other striated muscles is malleable in response to physiological and pathophysiological stressors, with potential implications for the maintenance of respiratory homeostasis. This review considers hypoxic adaptation of the diaphragm muscle, with a focus on functional, structural, and metabolic remodeling relevant to conditions such as high altitude and chronic respiratory disease. On the basis of emerging data in animal models, we posit that hypoxia is a significant driver of respiratory muscle plasticity, with evidence suggestive of both compensatory and deleterious adaptations in conditions of sustained exposure to low oxygen. Cellular strategies driving diaphragm remodeling during exposure to sustained hypoxia appear to confer hypoxic tolerance at the expense of peak force-generating capacity, a key functional parameter that correlates with patient morbidity and mortality. Changes include, but are not limited to: redox-dependent activation of hypoxia-inducible factor (HIF) and MAP kinases; time-dependent carbonylation of key metabolic and functional proteins; decreased mitochondrial respiration; activation of atrophic signaling and increased proteolysis; and altered functional performance. Diaphragm muscle weakness may be a signature effect of sustained hypoxic exposure. We discuss the putative role of reactive oxygen species as mediators of both advantageous and disadvantageous adaptations of diaphragm muscle to sustained hypoxia, and the role of antioxidants in mitigating adverse effects of chronic hypoxic stress on respiratory muscle function.
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Affiliation(s)
- Philip Lewis
- Department of Physiology, School of Medicine, University College CorkCork, Ireland; Environmental Medicine and Preventative Research, Institute and Policlinic for Occupational Medicine, University of CologneCologne, Germany
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, University College Cork Cork, Ireland
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12
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Yue L, Yao H. Mitochondrial dysfunction in inflammatory responses and cellular senescence: pathogenesis and pharmacological targets for chronic lung diseases. Br J Pharmacol 2016; 173:2305-18. [PMID: 27189175 DOI: 10.1111/bph.13518] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 04/04/2016] [Accepted: 05/05/2016] [Indexed: 12/16/2022] Open
Abstract
Mitochondria are dynamic organelles, which couple the various cellular processes that regulate metabolism, cell proliferation and survival. Environmental stress can cause mitochondrial dysfunction and dynamic changes including reduced mitochondrial biogenesis, oxidative phosphorylation and ATP production, as well as mitophagy impairment, which leads to increased ROS, inflammatory responses and cellular senescence. Oxidative stress, inflammation and cellular senescence all have important roles in the pathogenesis of chronic lung diseases, such as chronic obstructive pulmonary disease, pulmonary fibrosis and bronchopulmonary dysplasia. In this review, we discuss the current state on how mitochondrial dysfunction affects inflammatory responses and cellular senescence, the mechanisms of mitochondrial dysfunction underlying the pathogenesis of chronic lung diseases and the potential of mitochondrial transfer and replacement as treatments for these diseases.
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Affiliation(s)
- Li Yue
- Department of Orthopaedics and Rehabilitation, University of Rochester, Rochester, NY, USA
| | - Hongwei Yao
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University Alpert Medical School, Providence, RI, USA
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13
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Taivassalo T, Hussain SN. Contribution of the Mitochondria to Locomotor Muscle Dysfunction in Patients With COPD. Chest 2016; 149:1302-12. [DOI: 10.1016/j.chest.2015.11.021] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 11/09/2015] [Accepted: 11/24/2015] [Indexed: 11/29/2022] Open
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14
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Barreiro E, Gea J. Molecular and biological pathways of skeletal muscle dysfunction in chronic obstructive pulmonary disease. Chron Respir Dis 2016; 13:297-311. [PMID: 27056059 DOI: 10.1177/1479972316642366] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) will be a major leading cause of death worldwide in the near future. Weakness and atrophy of the quadriceps are associated with a significantly poorer prognosis and increased mortality in COPD. Despite that skeletal muscle dysfunction may affect both respiratory and limb muscle groups in COPD, the latter are frequently more severely affected. Therefore, muscle dysfunction in COPD is a common systemic manifestation that should be evaluated on routine basis in clinical settings. In the present review, several aspects of COPD muscle dysfunction are being reviewed, with special emphasis on the underlying biological mechanisms. Figures on the prevalence of COPD muscle dysfunction and the most relevant etiologic contributors are also provided. Despite that ongoing research will shed light into the contribution of additional mechanisms to COPD muscle dysfunction, current knowledge points toward the involvement of a wide spectrum of cellular and molecular events that are differentially expressed in respiratory and limb muscles. Such mechanisms are thoroughly described in the article. The contribution of epigenetic events on COPD muscle dysfunction is also reviewed. We conclude that in view of the latest discoveries, from now, on new avenues of research should be designed to specifically target cellular mechanisms and pathways that impair muscle mass and function in COPD using pharmacological strategies and/or exercise training modalities.
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Affiliation(s)
- Esther Barreiro
- Department of Respiratory Medicine, Muscle and Respiratory System Research Unit (URMAR), Institute of Medical Research of Hospital del Mar (IMIM)-Hospital del Mar, Barcelona, Spain Department of Health Sciences (CEXS), Universitat Pompeu Fabra, Barcelona, Spain Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Barcelona, Spain
| | - Joaquim Gea
- Department of Respiratory Medicine, Muscle and Respiratory System Research Unit (URMAR), Institute of Medical Research of Hospital del Mar (IMIM)-Hospital del Mar, Barcelona, Spain Department of Health Sciences (CEXS), Universitat Pompeu Fabra, Barcelona, Spain Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Barcelona, Spain
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Abstract
Mitochondria are a distinguishing feature of eukaryotic cells. Best known for their critical function in energy production via oxidative phosphorylation (OXPHOS), mitochondria are essential for nutrient and oxygen sensing and for the regulation of critical cellular processes, including cell death and inflammation. Such diverse functional roles for organelles that were once thought to be simple may be attributed to their distinct heteroplasmic genome, exclusive maternal lineage of inheritance, and ability to generate signals to communicate with other cellular organelles. Mitochondria are now thought of as one of the cell's most sophisticated and dynamic responsive sensing systems. Specific signatures of mitochondrial dysfunction that are associated with disease pathogenesis and/or progression are becoming increasingly important. In particular, the centrality of mitochondria in the pathological processes and clinical phenotypes associated with a range of lung diseases is emerging. Understanding the molecular mechanisms regulating the mitochondrial processes of lung cells will help to better define phenotypes and clinical manifestations associated with respiratory disease and to identify potential diagnostic and therapeutic targets.
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16
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Gea J, Pascual S, Casadevall C, Orozco-Levi M, Barreiro E. Muscle dysfunction in chronic obstructive pulmonary disease: update on causes and biological findings. J Thorac Dis 2015; 7:E418-38. [PMID: 26623119 DOI: 10.3978/j.issn.2072-1439.2015.08.04] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Respiratory and/or limb muscle dysfunction, which are frequently observed in chronic obstructive pulmonary disease (COPD) patients, contribute to their disease prognosis irrespective of the lung function. Muscle dysfunction is caused by the interaction of local and systemic factors. The key deleterious etiologic factors are pulmonary hyperinflation for the respiratory muscles and deconditioning secondary to reduced physical activity for limb muscles. Nonetheless, cigarette smoke, systemic inflammation, nutritional abnormalities, exercise, exacerbations, anabolic insufficiency, drugs and comorbidities also seem to play a relevant role. All these factors modify the phenotype of the muscles, through the induction of several biological phenomena in patients with COPD. While respiratory muscles improve their aerobic phenotype (percentage of oxidative fibers, capillarization, mitochondrial density, enzyme activity in the aerobic pathways, etc.), limb muscles exhibit the opposite phenotype. In addition, both muscle groups show oxidative stress, signs of damage and epigenetic changes. However, fiber atrophy, increased number of inflammatory cells, altered regenerative capacity; signs of apoptosis and autophagy, and an imbalance between protein synthesis and breakdown are rather characteristic features of the limb muscles, mostly in patients with reduced body weight. Despite that significant progress has been achieved in the last decades, full elucidation of the specific roles of the target biological mechanisms involved in COPD muscle dysfunction is still required. Such an achievement will be crucial to adequately tackle with this relevant clinical problem of COPD patients in the near-future.
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Affiliation(s)
- Joaquim Gea
- Servei de Pneumologia, Muscle & Respiratory System Research Unit (URMAR), Hospital del Mar-I.M.I.M., Experimental Sciences and Health Department (CEXS), Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Catalonia, Spain
| | - Sergi Pascual
- Servei de Pneumologia, Muscle & Respiratory System Research Unit (URMAR), Hospital del Mar-I.M.I.M., Experimental Sciences and Health Department (CEXS), Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Catalonia, Spain
| | - Carme Casadevall
- Servei de Pneumologia, Muscle & Respiratory System Research Unit (URMAR), Hospital del Mar-I.M.I.M., Experimental Sciences and Health Department (CEXS), Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Catalonia, Spain
| | - Mauricio Orozco-Levi
- Servei de Pneumologia, Muscle & Respiratory System Research Unit (URMAR), Hospital del Mar-I.M.I.M., Experimental Sciences and Health Department (CEXS), Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Catalonia, Spain
| | - Esther Barreiro
- Servei de Pneumologia, Muscle & Respiratory System Research Unit (URMAR), Hospital del Mar-I.M.I.M., Experimental Sciences and Health Department (CEXS), Universitat Pompeu Fabra, CIBERES, ISCIII, Barcelona, Catalonia, Spain
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Baldi S, Pinna GD, Bruschi C, Caldara F, Maestri R, Dacosto E, Rezzani A, Popovich E, Bellinzona E, Crotti P, Montemartini S, Fracchia C. Medicinal clays improve the endurance of loaded inspiratory muscles in COPD: a randomized clinical trial of nonpharmacological treatment. Int J Chron Obstruct Pulmon Dis 2015; 10:2235-48. [PMID: 26604728 PMCID: PMC4629956 DOI: 10.2147/copd.s87999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Inspiratory resistive breathing (IRB) challenges affect respiratory muscle endurance in healthy individuals, which is considered to be an interleukin 6 (IL-6)-dependent mechanism. Whether nonpharmacological thermal therapies promote the endurance of loaded inspiratory muscles in chronic obstructive pulmonary disease (COPD) is unclear. The objectives of this study were to compare the effects of two thermal interventions on endurance time (ET) and plasma IL-6 concentration following an IRB challenge. METHODS This study was a randomized, parallel-group, unblinded clinical trial in a single-center setting. Forty-two patients (aged 42-76 years) suffering from mild to severe COPD participated in this study. Both groups completed 12 sessions of the mud bath therapy (MBT) (n=22) or leisure thermal activity (LTA) (n=19) in a thermal spa center in Italy. Pre- and postintervention spirometry, maximum inspiratory pressure, and plasma mediators were obtained and ET and endurance oxygen expenditure (VO2Endur) were measured following IRB challenge at 40% of maximum inspiratory pressure. RESULTS There was no difference in ΔIL-6 between the intervention groups. But, IRB challenge increased cytokine IL-6 plasma levels systematically. The effect size was small. A statistically significant treatment by IRB challenge effect existed in ET, which significantly increased in the MBT group (P=0.003). In analysis of covariance treatment by IRB challenge analysis with LnVO2Endur as the dependent variable, ΔIL-6 after intervention predicted LnVO2Endur in the MBT group, but not in the LTA group. Adverse events occurred in two individuals in the MBT group, but they were mainly transient. One patient in the LTA group dropped out. CONCLUSION MBT model improves ET upon a moderate IRB challenge, indicating the occurrence of a training effect. The LnVO2Endur/ΔIL-6 suggests a physiologic adaptive mechanism in respiratory muscles of COPD patients allocated to treatment. Both thermal interventions are safe.
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Affiliation(s)
- Simonetta Baldi
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Gian Domenico Pinna
- Department of Biomedical Engineering, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia), AbanoTerme, Padua, Italy
| | - Claudio Bruschi
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Fabrizio Caldara
- Center of Thermal Studies Pietro d’Abano, AbanoTerme, Padua, Italy
| | - Roberto Maestri
- Department of Biomedical Engineering, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia), AbanoTerme, Padua, Italy
| | - Elena Dacosto
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Antonella Rezzani
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Ermanno Popovich
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Ezio Bellinzona
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Paola Crotti
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Silvia Montemartini
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
| | - Claudio Fracchia
- Department of Pneumology, Scientific Institute of Montescano, Salvatore Maugeri Foundation, Istituto Di Ricovero e Cura a Carattere Scientifico, Montescano (Pavia)
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Guidelines for the Evaluation and Treatment of Muscle Dysfunction in Patients With Chronic Obstructive Pulmonary Disease. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.arbr.2015.04.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Barreiro E, Bustamante V, Cejudo P, Gáldiz JB, Gea J, de Lucas P, Martínez-Llorens J, Ortega F, Puente-Maestu L, Roca J, Rodríguez-González Moro JM. Guidelines for the evaluation and treatment of muscle dysfunction in patients with chronic obstructive pulmonary disease. Arch Bronconeumol 2015; 51:384-95. [PMID: 26072153 DOI: 10.1016/j.arbres.2015.04.011] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 03/24/2015] [Accepted: 04/23/2015] [Indexed: 01/09/2023]
Abstract
In patients with chronic obstructive pulmonary disease (COPD), skeletal muscle dysfunction is a major comorbidity that negatively impacts their exercise capacity and quality of life. In the current guidelines, the most recent literature on the various aspects of COPD muscle dysfunction has been included. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) scale has been used to make evidence-based recommendations on the different features. Compared to a control population, one third of COPD patients exhibited a 25% decline in quadriceps muscle strength, even at early stages of their disease. Although both respiratory and limb muscles are altered, the latter are usually more severely affected. Numerous factors and biological mechanisms are involved in the etiology of COPD muscle dysfunction. Several tests are proposed in order to diagnose and evaluate the degree of muscle dysfunction of both respiratory and limb muscles (peripheral), as well as to identify the patients' exercise capacity (six-minute walking test and cycloergometry). Currently available therapeutic strategies including the different training modalities and pharmacological and nutritional support are also described.
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Affiliation(s)
- Esther Barreiro
- Servei de Pneumologia, Unitat de Recerca en Múscul i Aparell Respiratori (URMAR), IMIM-Hospital del Mar, CEXS, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona (PRBB), Barcelona, España; CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, España.
| | - Víctor Bustamante
- Hospital Universitario Basurto, Osakidetza, Departamento de Medicina, Universidad del País Vasco, Bilbao, España; Servicio de Neumología y Unidad de Investigación, Hospital de Cruces, Universidad del País Vasco , Barakaldo, España
| | - Pilar Cejudo
- Servicio de Neumología y Unidad de Investigación, Hospital de Cruces, Universidad del País Vasco , Barakaldo, España
| | - Juan B Gáldiz
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, España; Hospital Universitario Basurto, Osakidetza, Departamento de Medicina, Universidad del País Vasco, Bilbao, España
| | - Joaquim Gea
- Servei de Pneumologia, Unitat de Recerca en Múscul i Aparell Respiratori (URMAR), IMIM-Hospital del Mar, CEXS, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona (PRBB), Barcelona, España; CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, España
| | - Pilar de Lucas
- Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Hospital Universitario Virgen del Rocío, Sevilla, España
| | - Juana Martínez-Llorens
- Servei de Pneumologia, Unitat de Recerca en Múscul i Aparell Respiratori (URMAR), IMIM-Hospital del Mar, CEXS, Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona (PRBB), Barcelona, España; CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, España
| | - Francisco Ortega
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, España; Servicio de Neumología y Unidad de Investigación, Hospital de Cruces, Universidad del País Vasco , Barakaldo, España
| | - Luis Puente-Maestu
- Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Hospital Universitario Virgen del Rocío, Sevilla, España
| | - Josep Roca
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, España; Servicio de Neumología, Hospital General Gregorio Marañón, Universidad Complutense de Madrid, Madrid, España; Servei de Pneumologia, Hospital Clínic de Barcelona, Barcelona, España
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Maltais F, Decramer M, Casaburi R, Barreiro E, Burelle Y, Debigaré R, Dekhuijzen PNR, Franssen F, Gayan-Ramirez G, Gea J, Gosker HR, Gosselink R, Hayot M, Hussain SNA, Janssens W, Polkey MI, Roca J, Saey D, Schols AMWJ, Spruit MA, Steiner M, Taivassalo T, Troosters T, Vogiatzis I, Wagner PD. An official American Thoracic Society/European Respiratory Society statement: update on limb muscle dysfunction in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2014; 189:e15-62. [PMID: 24787074 DOI: 10.1164/rccm.201402-0373st] [Citation(s) in RCA: 667] [Impact Index Per Article: 66.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Limb muscle dysfunction is prevalent in chronic obstructive pulmonary disease (COPD) and it has important clinical implications, such as reduced exercise tolerance, quality of life, and even survival. Since the previous American Thoracic Society/European Respiratory Society (ATS/ERS) statement on limb muscle dysfunction, important progress has been made on the characterization of this problem and on our understanding of its pathophysiology and clinical implications. PURPOSE The purpose of this document is to update the 1999 ATS/ERS statement on limb muscle dysfunction in COPD. METHODS An interdisciplinary committee of experts from the ATS and ERS Pulmonary Rehabilitation and Clinical Problems assemblies determined that the scope of this document should be limited to limb muscles. Committee members conducted focused reviews of the literature on several topics. A librarian also performed a literature search. An ATS methodologist provided advice to the committee, ensuring that the methodological approach was consistent with ATS standards. RESULTS We identified important advances in our understanding of the extent and nature of the structural alterations in limb muscles in patients with COPD. Since the last update, landmark studies were published on the mechanisms of development of limb muscle dysfunction in COPD and on the treatment of this condition. We now have a better understanding of the clinical implications of limb muscle dysfunction. Although exercise training is the most potent intervention to address this condition, other therapies, such as neuromuscular electrical stimulation, are emerging. Assessment of limb muscle function can identify patients who are at increased risk of poor clinical outcomes, such as exercise intolerance and premature mortality. CONCLUSIONS Limb muscle dysfunction is a key systemic consequence of COPD. However, there are still important gaps in our knowledge about the mechanisms of development of this problem. Strategies for early detection and specific treatments for this condition are also needed.
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Abstract
Heart failure (HF) is a complex chronic clinical syndrome. Energy deficit is considered to be a key contributor to the development of both cardiac and skeletal myopathy. In HF, several components of cardiac and skeletal muscle bioenergetics are altered, such as oxygen availability, substrate oxidation, mitochondrial ATP production, and ATP transfer to the contractile apparatus via the creatine kinase shuttle. This review focuses on alterations in mitochondrial biogenesis and respirasome organization, substrate oxidation coupled with ATP synthesis in the context of their contribution to the chronic energy deficit, and mechanical dysfunction of the cardiac and skeletal muscle in HF. We conclude that HF is associated with decreased mitochondrial biogenesis and function in both heart and skeletal muscle, supporting the concept of a systemic mitochondrial cytopathy. The sites of mitochondrial defects are located within the electron transport and phosphorylation apparatus and differ with the etiology and progression of HF in the two mitochondrial populations (subsarcolemmal and interfibrillar) of cardiac and skeletal muscle. The roles of adrenergic stimulation, the renin-angiotensin system, and cytokines are evaluated as factors responsible for the systemic energy deficit. We propose a cyclic AMP-mediated mechanism by which increased adrenergic stimulation contributes to the mitochondrial dysfunction.
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Gagnon P, Guenette JA, Langer D, Laviolette L, Mainguy V, Maltais F, Ribeiro F, Saey D. Pathogenesis of hyperinflation in chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2014; 9:187-201. [PMID: 24600216 PMCID: PMC3933347 DOI: 10.2147/copd.s38934] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a preventable and treatable lung disease characterized by airflow limitation that is not fully reversible. In a significant proportion of patients with COPD, reduced lung elastic recoil combined with expiratory flow limitation leads to lung hyperinflation during the course of the disease. Development of hyperinflation during the course of COPD is insidious. Dynamic hyperinflation is highly prevalent in the advanced stages of COPD, and new evidence suggests that it also occurs in many patients with mild disease, independently of the presence of resting hyperinflation. Hyperinflation is clinically relevant for patients with COPD mainly because it contributes to dyspnea, exercise intolerance, skeletal muscle limitations, morbidity, and reduced physical activity levels associated with the disease. Various pharmacological and nonpharmacological interventions have been shown to reduce hyperinflation and delay the onset of ventilatory limitation in patients with COPD. The aim of this review is to address the more recent literature regarding the pathogenesis, assessment, and management of both static and dynamic lung hyperinflation in patients with COPD. We also address the influence of biological sex and obesity and new developments in our understanding of hyperinflation in patients with mild COPD and its evolution during progression of the disease.
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Affiliation(s)
- Philippe Gagnon
- Faculté de Médecine, Université Laval, Québec, QC, Canada ; Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Jordan A Guenette
- Centre for Heart Lung Innovation, University of British Columbia, St Paul's Hospital, Vancouver, BC, Canada ; Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - Daniel Langer
- Department of Kinesiology and Rehabilitation Sciences, KU Leuven, Leuven, Belgium
| | - Louis Laviolette
- Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
| | | | - François Maltais
- Faculté de Médecine, Université Laval, Québec, QC, Canada ; Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Fernanda Ribeiro
- Faculté de Médecine, Université Laval, Québec, QC, Canada ; Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Didier Saey
- Faculté de Médecine, Université Laval, Québec, QC, Canada ; Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada
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Vogiatzis I, Zakynthinos S. Factors limiting exercise tolerance in chronic lung diseases. Compr Physiol 2013; 2:1779-817. [PMID: 23723024 DOI: 10.1002/cphy.c110015] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The major limitation to exercise performance in patients with chronic lung diseases is an issue of great importance since identifying the factors that prevent these patients from carrying out activities of daily living provides an important perspective for the choice of the appropriate therapeutic strategy. The factors that limit exercise capacity may be different in patients with different disease entities (i.e., chronic obstructive, restrictive or pulmonary vascular lung disease) or disease severity and ultimately depend on the degree of malfunction or miss coordination between the different physiological systems (i.e., respiratory, cardiovascular and peripheral muscles). This review focuses on patients with chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD) and pulmonary vascular disease (PVD). ILD and PVD are included because there is sufficient experimental evidence for the factors that limit exercise capacity and because these disorders are representative of restrictive and pulmonary vascular disorders, respectively. A great deal of emphasis is given, however, to causes of exercise intolerance in COPD mainly because of the plethora of research findings that have been published in this area and also because exercise intolerance in COPD has been used as a model for understanding the interactions of different pathophysiologic mechanisms in exercise limitation. As exercise intolerance in COPD is recognized as being multifactorial, the impacts of the following factors on patients' exercise capacity are explored from an integrative physiological perspective: (i) imbalance between the ventilatory capacity and requirement; (ii) imbalance between energy demands and supplies to working respiratory and peripheral muscles; and (iii) peripheral muscle intrinsic dysfunction/weakness.
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Affiliation(s)
- Ioannis Vogiatzis
- Department of Physical Education and Sport Sciences, National and Kapodistrian University of Athens, Greece.
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Marinari S, Manigrasso MR, De Benedetto F. Effects of nutraceutical diet integration, with coenzyme Q10 (Q-Ter multicomposite) and creatine, on dyspnea, exercise tolerance, and quality of life in COPD patients with chronic respiratory failure. Multidiscip Respir Med 2013; 8:40. [PMID: 23800154 PMCID: PMC3707735 DOI: 10.1186/2049-6958-8-40] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 06/06/2013] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The protein-calorie malnutrition, resulting in muscle mass loss, frequently occurs in severe COPD patients with chronic respiratory failure (CRF), causing dyspnea, reduced exercise tolerance and impaired quality of life.The cause of this occurrence is an intake-output energy imbalance. A documented deficit of phosphocreatine and reduced mithocondrial energy production can contribute to this imbalance.Aim of this study is to verify whether a dietary supplementation with creatine and coenzyme Q10, important mitochondrial function factors, is able to influence this mechanism leading to a dyspnea reduction and improving exercise tolerance and quality of life. METHODS 55 COPD patients with chronic respiratory failure (in long term O2 therapy), in stable phase of the disease and without severe comorbidities were assigned (double-blind, randomized) to: group A (30 patients) with daily dietary supplementation with Creatine 340 mg + 320 mg Coenzyme Q-Ter (Eufortyn®, Scharper Therapeutics Srl) for 2 months whereas Group B (25 patients) received placebo.All patients continued the same diet, rehabilitation and therapy during the study. At recruitment (T0) and after 2 months (T1), patients were submitted to medical history, anthropometry (BMI), bioelectrical impedance, arterial blood gas analysis, evaluation of dyspnea (VAS, Borg, BDI, MRC) and functional independence (ADL), 6-minute walk test (6MWT) and quality of life questionnaire (SGRQ). At 6 months and 1 year, a telephone follow up was conducted on exacerbations number. RESULTS No significant difference was detected at baseline (T0) in the 2 groups. After 2 months of therapy (T1) the FFMI increased in the daily dietary supplementation group (+ 3.7 %) and decreased in the placebo group (- 0.6 %), resulting in a statistically significant (p < 0.001) treatment difference. Statistically significant treatment differences, favouring daily dietary supplementation group, were also seen for the 6MWT comparison. Group A patients also showed significant: 1) improvement in the degree of dyspnea (VAS: p < 0.05; Borg: p < 0.05; MRC: p < 0.001; BDI1: p < 0.05; BDI3: p < 0.03), and independence level in activities of daily living (p < 0.03); 2) improvement in quality of life in activity section (- 6.63 pt) and in total score (- 5.43 pt); 3) exacerbation number decrease (p < 0.02). No significant differences were found (end of study vs baseline) in group B. CONCLUSIONS The nutraceutical diet integration with Q-Ter and creatine, in COPD patients with CRF in O2TLT induced an increasing lean body mass and exercise tolerance, reducing dyspnea, quality of life and exacerbations. These results provide a first demonstration that acting on protein synthesis and muscular efficiency can significantly modify the systemic consequences of the disease.
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Abstract
Muscle dysfunction often occurs in patients with chronic obstructive pulmonary disease (COPD) and may involve both respiratory and locomotor (peripheral) muscles. The loss of strength and/or endurance in the former can lead to ventilatory insufficiency, whereas in the latter it limits exercise capacity and activities of daily life. Muscle dysfunction is the consequence of complex interactions between local and systemic factors, frequently coexisting in COPD patients. Pulmonary hyperinflation along with the increase in work of breathing that occur in COPD appear as the main contributing factors to respiratory muscle dysfunction. By contrast, deconditioning seems to play a key role in peripheral muscle dysfunction. However, additional systemic factors, including tobacco smoking, systemic inflammation, exercise, exacerbations, nutritional and gas exchange abnormalities, anabolic insufficiency, comorbidities and drugs, can also influence the function of both respiratory and peripheral muscles, by inducing modifications in their local microenvironment. Under all these circumstances, protein metabolism imbalance, oxidative stress, inflammatory events, as well as muscle injury may occur, determining the final structure and modulating the function of different muscle groups. Respiratory muscles show signs of injury as well as an increase in several elements involved in aerobic metabolism (proportion of type I fibers, capillary density, and aerobic enzyme activity) whereas limb muscles exhibit a loss of the same elements, injury, and a reduction in fiber size. In the present review we examine the current state of the art of the pathophysiology of muscle dysfunction in COPD.
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Affiliation(s)
- Joaquim Gea
- Servei de Pneumologia, Hospital del Mar-IMIM, Universitat Pompeu Fabra, Barcelona, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), ISCIII, Bunyola, Spain
| | - Alvar Agustí
- CIBER de Enfermedades Respiratorias (CIBERES), ISCIII, Bunyola, Spain
- Servei de Pneumologia, Institut del Tòrax. Hospital Clínic-IDIBAPS, Universitat de Barcelona, Barcelona, Spain; and
- Fundació Investigació Sanitària Illes Balears (FISIB), Mallorca, Spain
| | - Josep Roca
- CIBER de Enfermedades Respiratorias (CIBERES), ISCIII, Bunyola, Spain
- Servei de Pneumologia, Institut del Tòrax. Hospital Clínic-IDIBAPS, Universitat de Barcelona, Barcelona, Spain; and
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Puente-Maestu L, Lázaro A, Humanes B. Metabolic derangements in COPD muscle dysfunction. J Appl Physiol (1985) 2013; 114:1282-90. [PMID: 23288549 DOI: 10.1152/japplphysiol.00815.2012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Mitochondrial muscle alterations are common in patients with chronic obstructive pulmonary disease (COPD) and manifest mainly as decreased oxidative capacity and excessive production of reactive oxygen species (ROS). The significant loss of oxidative capacity observed in the quadriceps of COPD patients is mainly due to reduced mitochondrial content in the fibers, a finding consistent with the characteristic loss of type I fibers observed in that muscle. Decreased oxidative capacity does not directly limit maximum performance; however, it is associated with increased lactate production at lower exercise intensity and reduced endurance. Since type I fiber atrophy does not occur in respiratory muscles, the loss of such fibers in the quadriceps could be to the result of disuse. In contrast, excessive production of ROS and oxidative stress are observed in both the respiratory muscles and the quadriceps of COPD patients. The causes of increased ROS production are not clear, and a number of different mechanisms can play a role. Several mitochondrial alterations in the quadriceps of COPD patients are similar to those observed in diabetic patients, thus suggesting a role for muscle alterations in this comorbidity. Amino acid metabolism is also altered. Expression of peroxisome proliferator-activated receptor-γ coactivator-1α mRNA is low in the quadriceps of COPD patients, which could also be a consequence of type I fiber loss; nevertheless, its response to exercise is not altered. Patterns of muscle cytochrome oxidase gene activation after training differ between COPD patients and healthy subjects, and the profile is consistent with hypoxic stress, even in nonhypoxic patients.
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Affiliation(s)
- Luis Puente-Maestu
- Servicio de Neumología, Hospital General Gregorio Marañón, Universidad Complutense de Madrid, Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
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Levine S, Bashir MH, Clanton TL, Powers SK, Singhal S. COPD elicits remodeling of the diaphragm and vastus lateralis muscles in humans. J Appl Physiol (1985) 2012; 114:1235-45. [PMID: 23264538 DOI: 10.1152/japplphysiol.01121.2012] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A profound remodeling of the diaphragm and vastus lateralis (VL) occurs in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD). In this mini-review, we discuss the following costal diaphragm remodeling features noted in patients with moderate-to-severe COPD: 1) deletion of serial sarcomeres, 2) increased proportion of slow-twitch fibers, 3) fast-to-slow isoform shift in sarco(endo)plasmic reticulum Ca(2+)-ATPase, 4) increased capacity of oxidative metabolism, 5) oxidative stress, and 6) myofiber atrophy. We then present the sole feature of diaphragm remodeling noted in mild-to-moderate COPD under the heading "MyHC and contractile remodeling noted in mild-to-moderate COPD." The importance of VL remodeling in COPD patients as a prognostic indicator as well as a major determinant of the ability to carry out activities of daily living is well accepted. We present the remodeling of the VL noted in COPD patients under the following headings: 1) Decrease in proportion of slow-twitch fibers, 2) Decreased activity of oxidative pathways, 3) Oxidative and nitrosative stress, and 4) Myofiber atrophy. For each of the remodeling features noted in both the VL and costal diaphragm of COPD patients, we present mechanisms that are currently thought to mediate these changes as well as the pathophysiology of each remodeling feature. We hope that our mechanistic presentation stimulates research in this area that focuses on improving the ability of COPD patients to carry out increased activities of daily living.
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Affiliation(s)
- Sanford Levine
- Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania 19035, USA.
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Sullo N, Roviezzo F, Matteis M, Spaziano G, Del Gaudio S, Lombardi A, Lucattelli M, Polverino F, Lungarella G, Cirino G, Rossi F, D'Agostino B. Skeletal muscle oxidative metabolism in an animal model of pulmonary emphysema: formoterol and skeletal muscle dysfunction. Am J Respir Cell Mol Biol 2012; 48:198-203. [PMID: 23144332 DOI: 10.1165/rcmb.2012-0167oc] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Skeletal muscle dysfunction is a significant contributor to exercise limitation in pulmonary emphysema. This study investigated skeletal muscle oxidative metabolism before and after aerosol exposure to a long-acting β-agonist (LABA), such as formoterol, in the pallid mouse (B6.Cg-Pldnpa/J), which has a deficiency in serum α(1)-antitrypsin (α(1)-PI) and develops spontaneous pulmonary emphysema. C57 BL/6J and its congener pallid mice of 8-12 and 16 months of age were treated with vehicle or formoterol aerosol challenge for 120 seconds. Morphological and morphometric studies and evaluations of mitochondrial adenosine diphosphate-stimulated respiration and of cytochrome oxidase activity on skeletal muscle were performed. Moreover, the mtDNA content in skeletal muscle and the mediators linked to muscle mitochondrial function and biogenesis, as well as TNF-α and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), were also evaluated. The lungs of pallid mice at 12 and 16 months of age showed patchy areas of airspace enlargements, with the destruction of alveolar septa. No significant differences were observed in basal values of mitochondrial skeletal muscle oxidative processes between C57 BL/6J and pallid mice. Exposure to LABA significantly improved mitochondrial skeletal muscle oxidative processes in emphysematous mice, where the mtDNA content was significantly higher with respect to 8-month-old pallid mice. This effect was compared with a significant increase of PGC-1α in skeletal muscles of 16-month-old pallid mice, with no significant changes in TNF-α concentrations. In conclusion, in emphysematous mice that showed an increased mtDNA content, exposure to inhaled LABA can improve mitochondrial skeletal muscle oxidative processes. PGC-1α may serve as a possible mediator of this effect.
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Affiliation(s)
- Nikol Sullo
- Section of Pharmacology, Department of Experimental Medicine, Faculty of Medicine and Surgery, Second University of Naples, Via Costantinopoli 16, 80136 Naples, Italy
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Zuo L, Hallman AH, Yousif MK, Chien MT. Oxidative stress, respiratory muscle dysfunction, and potential therapeutics in chronic obstructive pulmonary disease. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11515-012-1251-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Caron MA, Debigaré R, Dekhuijzen PNR, Maltais F. [Diaphragm and skeletal muscle dysfunction in COPD]. Rev Mal Respir 2011; 28:1250-64. [PMID: 22152934 DOI: 10.1016/j.rmr.2011.04.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Accepted: 04/04/2011] [Indexed: 11/16/2022]
Abstract
INTRODUCTION Chronic obstructive pulmonary disease (COPD) is often accompanied by skeletal muscle alterations, resulting in enhanced morbidity and mortality. STATE OF THE ART Many studies have highlighted important structural and biochemical modifications in limb and respiratory muscles in COPD. Reviewing the similarities and differences between the two most studied muscles in COPD, the quadriceps and the diaphragm, may provide important clues about the mechanisms dictating muscle changes that occur in this disease. PERSPECTIVES Though these two muscle groups share a common systemic environment, discrepancies are observed in their respective alterations. These phenotypic differences suggest that, in addition to systemic factors, the local microenvironment must participate in the reorganization seen in these two muscles in COPD. CONCLUSIONS The current review introduces the alterations observed in the quadriceps and diaphragm in the context of COPD and suggests possible signaling pathways involved in the development of muscle dysfunction.
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Affiliation(s)
- M-A Caron
- Centre de recherche, institut universitaire de cardiologie et de pneumologie de Québec, université Laval, 2725 chemin Ste-Foy, Québec, Canada
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Estenne M, Fessler HE, DeCamp MM. Lung transplantation and lung volume reduction surgery. Compr Physiol 2011; 1:1437-71. [PMID: 23733648 DOI: 10.1002/cphy.c100044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Since the publication of the last edition of the Handbook of Physiology, lung transplantation has become widely available, via specialized centers, for a variety of end-stage lung diseases. Lung volume reduction surgery, a procedure for emphysema first conceptualized in the 1950s, electrified the pulmonary medicine community when it was rediscovered in the 1990s. In parallel with their technical and clinical refinement, extensive investigation has explored the unique physiology of these procedures. In the case of lung transplantation, relevant issues include the discrepant mechanical function of the donor lungs and recipient thorax, the effects of surgical denervation, acute and chronic rejection, respiratory, chest wall, and limb muscle function, and response to exercise. For lung volume reduction surgery, there have been new insights into the counterintuitive observation that lung function in severe emphysema can be improved by resecting the most diseased portions of the lungs. For both procedures, insights from physiology have fed back to clinicians to refine patient selection and to scientists to design clinical trials. This section will first provide an overview of the clinical aspects of these procedures, including patient selection, surgical techniques, complications, and outcomes. It then reviews the extensive data on lung and muscle function following transplantation and its complications. Finally, it reviews the insights from the last 15 years on the mechanisms whereby removal of lung from an emphysema patient can improve the function of the lung left behind.
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Affiliation(s)
- Marc Estenne
- Chest Service and Thoracic Transplantation Unit, Erasme University Hospital, Brussels, Belgium
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D'Agostino B, Polverino M, Cirino G, Lombardi A, Grassi B, Sullo N, Santoriello C, Polverino F, Orlotti D, Matteis M, Rossi F. Exercise capacity and cytochrome oxidase activity in muscle mitochondria of COPD patients. Respir Med 2010; 104:83-90. [DOI: 10.1016/j.rmed.2009.07.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 07/27/2009] [Accepted: 07/28/2009] [Indexed: 01/27/2023]
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Caron MA, Debigaré R, Dekhuijzen PNR, Maltais F. Comparative assessment of the quadriceps and the diaphragm in patients with COPD. J Appl Physiol (1985) 2009; 107:952-61. [PMID: 19359618 DOI: 10.1152/japplphysiol.00194.2009] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) and other chronic diseases such as heart failure are accompanied by skeletal muscle alterations that further enhance morbidity and mortality in affected individuals. Several studies have highlighted important structural and biochemical modifications in limb and respiratory muscles in COPD. Reviewing the similarities and differences between the two most studied muscles in COPD, the quadriceps and the diaphragm, may be helpful in providing important clues about the mechanisms underlying muscle changes associated with this disease. Although oxidative stress is present in both muscles, other muscle alterations are clearly distinct between the quadriceps and the diaphragm. For example, the oxidative metabolism varies in opposite directions, the diaphragm exhibiting increased resistance to fatigue while the quadriceps in COPD is characterized by premature fatigability. Differences in muscle phenotypic expression between the diaphragm and the quadriceps indicate that, in addition to systemic factors, the local microenvironment must participate in the reorganization seen in these two skeletal muscles in COPD.
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Affiliation(s)
- Marc-André Caron
- Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec, Canada G1V 4G5
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Clanton TL, Levine S. Respiratory muscle fiber remodeling in chronic hyperinflation: dysfunction or adaptation? J Appl Physiol (1985) 2009; 107:324-35. [PMID: 19359619 DOI: 10.1152/japplphysiol.00173.2009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The diaphragm and other respiratory muscles undergo extensive remodeling in both animal models of emphysema and in human chronic obstructive pulmonary disease, but the nature of the remodeling is different in many respects. One common feature is a shift toward improved endurance characteristics and increased oxidative capacity. Furthermore, both animals and humans respond to chronic hyperinflation by diaphragm shortening. Although in rodent models this clearly arises by deletion of sarcomeres in series, the mechanism has not been proven conclusively in human chronic obstructive pulmonary disease. Unique characteristics of the adaptation in human diaphragms include shifts to more predominant slow, type I fibers, expressing slower myosin heavy chain isoforms, and type I and type II fiber atrophy. Although some laboratories report reductions in specific force, this may be accounted for by decreases in myosin heavy chain content as the muscles become more oxidative and more efficient. More recent findings have reported reductions in Ca(2+) sensitivity and reduced myofibrillar elastic recoil. In contrast, in rodent models of disease, there is no consistent evidence for loss of specific force, no consistent shift in fiber populations, and atrophy is predominantly seen only in fast, type IIX fibers. This review challenges the hypothesis that the adaptations in human diaphragm represent a form of dysfunction, secondary to systemic disease, and suggest that most findings can as well be attributed to adaptive processes of a complex muscle responding to unique alterations in its working environment.
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Affiliation(s)
- Thomas L Clanton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida 32611, USA.
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Dopamine alleviation of diaphragm contractile dysfunction and reduction of deoxyribonucleic acid damage in rats. Heart Lung 2008; 37:132-43. [DOI: 10.1016/j.hrtlng.2007.05.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2006] [Accepted: 05/07/2007] [Indexed: 12/27/2022]
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Ottenheijm CAC, Heunks LMA, Dekhuijzen RPN. Diaphragm adaptations in patients with COPD. Respir Res 2008; 9:12. [PMID: 18218129 PMCID: PMC2248576 DOI: 10.1186/1465-9921-9-12] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2007] [Accepted: 01/24/2008] [Indexed: 01/03/2023] Open
Abstract
Inspiratory muscle weakness in patients with COPD is of major clinical relevance. For instance, maximum inspiratory pressure generation is an independent determinant of survival in severe COPD. Traditionally, inspiratory muscle weakness has been ascribed to hyperinflation-induced diaphragm shortening. However, more recently, invasive evaluation of diaphragm contractile function, structure, and biochemistry demonstrated that cellular and molecular alterations occur, of which several can be considered pathologic of nature. Whereas the fiber type shift towards oxidative type I fibers in COPD diaphragm is regarded beneficial, rendering the overloaded diaphragm more resistant to fatigue, the reduction of diaphragm fiber force generation in vitro likely contributes to diaphragm weakness. The reduced diaphragm force generation at single fiber level is associated with loss of myosin content in these fibers. Moreover, the diaphragm in COPD is exposed to oxidative stress and sarcomeric injury. This review postulates that the oxidative stress and sarcomeric injury activate proteolytic machinery, leading to contractile protein wasting and, consequently, loss of force generating capacity of diaphragm fibers in patients with COPD. Interestingly, several of these presumed pathologic alterations are already present early in the course of the disease (GOLD I/II), although these patients appear not limited in their daily life activities. Treatment of diaphragm dysfunction in COPD is complex since its etiology is unclear, but recent findings indicate the ubiquitin-proteasome pathway as a prime target to attenuate diaphragm wasting in COPD.
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Affiliation(s)
- Coen A C Ottenheijm
- Dept. of Molecular and Cellular Biology, University of Arizona, Tucson, USA.
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Wijnhoven HJH, Ennen L, Rodenburg RJT, Dekhuijzen PNR. Mitochondrial function in diaphragm of emphysematous hamsters after treatment with nandrolone. Int J Chron Obstruct Pulmon Dis 2007; 1:83-9. [PMID: 18046906 PMCID: PMC2706598 DOI: 10.2147/copd.2006.1.1.83] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Respiratory failure in patients with COPD may be caused by insufficient force production or insufficient endurance capacity of the respiratory muscles. Anabolic steroids may improve respiratory muscle function in COPD. The effect of anabolic steroids on mitochondrial function in the diaphragm in emphysema is unknown. In an emphysematous male hamster model, we investigated whether administration of the anabolic steroid nandrolone decanoate (ND) altered the activity of mitochondrial respiratory chain complexes in the diaphragm. The bodyweight of hamsters treated with ND was decreased after treatment compared with initial values, and serum testosterone levels were significantly lower in hamsters treated with ND than in control hamsters. No difference in the activity of mitochondrial respiratory chain complexes in the diaphragm between normal and emphysematous hamsters was observed. Treatment with ND did not change the activity of mitochondrial respiratory chain complexes in the diaphragm of both normal and emphysematous hamsters. In emphysematous hamsters, administration of ND decreased the activity of succinate:cytochrome c oxidoreductase compared with ND treatment in normal hamsters. We conclude that anabolic steroids have negative effects on the activity of succinate:cytochrome c oxidoreductase and anabolic status in this emphysematous hamster model.
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Affiliation(s)
- Hanneke J H Wijnhoven
- Department of Pulmonary Diseases, Institute for Fundamental and Clinical Human Movement Sciences, Radboud University, Nijmegen Medical Centre, Nijmegen, The Netherlands
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Abstract
Patients with sepsis-induced multiple organ failure often experience muscle fatigue in both locomotive and respiratory muscles. Muscle fatigue extends intensive care unit stay, mostly in the form of prolonged weaning from the ventilator, and the recovery period after intensive care unit treatment due to general muscle fatigue. Muscle mitochondria are the main determinant of muscle fatigue and fatigability. Derangements in mitochondrial function in locomotive muscles have been described extensively both in animal models and patients with sepsis. Also, in respiratory muscle, mitochondrial function and content are impaired during sepsis. However, in septic patients with multiple organ failure, in locomotive muscle, lower levels of energy-rich compounds accompany the decreased mitochondrial content, whereas in respiratory muscle, the decreased mitochondrial content has no effect on cellular energy metabolism.
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Affiliation(s)
- Katarina Fredriksson
- Department of Anesthesiology and Intensive Care, Clintec, Karolinska Institutet and University Hospital, Stockholm, Sweden
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40
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Witt JD, Guenette JA, Rupert JL, McKenzie DC, Sheel AW. Inspiratory muscle training attenuates the human respiratory muscle metaboreflex. J Physiol 2007; 584:1019-28. [PMID: 17855758 PMCID: PMC2277000 DOI: 10.1113/jphysiol.2007.140855] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We hypothesized that inspiratory muscle training (IMT) would attenuate the sympathetically mediated heart rate (HR) and mean arterial pressure (MAP) increases normally observed during fatiguing inspiratory muscle work. An experimental group (Exp, n = 8) performed IMT 6 days per week for 5 weeks at 50% of maximal inspiratory pressure (MIP), while a control group (Sham, n = 8) performed IMT at 10% MIP. Pre- and post-training, subjects underwent a eucapnic resistive breathing task (RBT) (breathing frequency = 15 breaths min(-1), duty cycle = 0.70) while HR and MAP were continuously monitored. Following IMT, MIP increased significantly (P < 0.05) in the Exp group (-125 +/- 10 to -146 +/- 12 cmH(2)O; mean +/- s.e.m.) but not in the Sham group (-141 +/- 11 to -148 +/- 11 cmH(2)O). Prior to IMT, the RBT resulted in significant increases in HR (Sham: 59 +/- 2 to 83 +/- 4 beats min(-1); Exp: 62 +/- 3 to 83 +/- 4 beats min(-1)) and MAP (Sham: 88 +/- 2 to 106 +/- 3 mmHg; Exp: 84 +/- 1 to 99 +/- 3 mmHg) in both groups relative to rest. Following IMT, the Sham group observed similar HR and MAP responses to the RBT while the Exp group failed to increase HR and MAP to the same extent as before (HR: 59 +/- 3 to 74 +/- 2 beats min(-1); MAP: 84 +/- 1 to 89 +/- 2 mmHg). This attenuated cardiovascular response suggests a blunted sympatho-excitation to resistive inspiratory work. We attribute our findings to a reduced activity of chemosensitive afferents within the inspiratory muscles and may provide a mechanism for some of the whole-body exercise endurance improvements associated with IMT.
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Affiliation(s)
- Jonathan D Witt
- School of Human Kinetics, University of British Columbia, Vancouver, BC, Canada
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Ottenheijm CAC, Heunks LMA, Dekhuijzen PNR. Diaphragm muscle fiber dysfunction in chronic obstructive pulmonary disease: toward a pathophysiological concept. Am J Respir Crit Care Med 2007; 175:1233-40. [PMID: 17413128 DOI: 10.1164/rccm.200701-020pp] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Inspiratory muscle weakness in patients with chronic obstructive pulmonary disease (COPD) is of major clinical relevance; maximum inspiratory pressure generation is an independent determinant of survival in severe COPD. Traditionally, inspiratory muscle weakness has been ascribed to hyperinflation-induced diaphragm shortening. However, more recently, invasive evaluation of diaphragm contractile function, structure, and biochemistry demonstrated that cellular and molecular alterations occur, of which several can be considered of pathologic nature. Although the fiber-type shift toward oxidative type I fibers in COPD diaphragm is regarded as beneficial, rendering the overloaded diaphragm more resistant to fatigue, the reduction of diaphragm fiber force generation in vitro likely contributes to diaphragm weakness. The reduced diaphragm force generation at single-fiber level is associated with loss of myosin content. Moreover, the diaphragm in COPD is exposed to oxidative stress and sarcomeric injury. The current Pulmonary Perspective postulates that the oxidative stress and sarcomeric injury activate proteolytic machinery, leading to contractile protein wasting and, consequently, loss of force-generating capacity of diaphragm fibers in patients with COPD. Interestingly, several of these presumed pathologic alterations are already present early in the course of the disease (GOLD I/II), although these patients do not appear to be limited in their daily-life activities. Therefore, investigating in vivo diaphragm function in mild to moderate COPD should be the focus of future research. Treatment of diaphragm dysfunction in COPD is complex because its etiology is unclear, but recent findings show promise for the use of proteasome inhibitors in syndromes associated with muscle wasting, such as the diaphragm in COPD.
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Affiliation(s)
- Coen A C Ottenheijm
- Department of Pulmonary Diseases, 454 Radboud University, Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
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Vandivier RW, Voelkel NF. The challenges of chronic obstructive pulmonary diseases (COPD)--a perspective. COPD 2007; 2:177-84. [PMID: 17136979 DOI: 10.1081/copd-200050676] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Chronic Obstructive Pulmonary Disease (COPD) is an inflammatory disease, primarily caused by cigarette smoke, which will soon become the third leading cause of death globally. Despite the importance of the problem, our real understanding of the biological underpinnings of COPD remains incomplete. Consequently, our first-line therapies, while helpful, are not yet as effective as they need to be. In this review, we will focus on these challenges and more, including the role of impaired tissue repair and adaptive immunity in disease pathogenesis, determining who may be at risk, describing COPD phenotypes and potential biomarkers. New ideas for chronic disease management and prevention of exacerbations will also be discussed. While much remains to be accomplished, meeting these challenges will bring rewards because what we learn will have implications for the understanding and treatment of chronic inflammatory diseases beyond COPD.
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Affiliation(s)
- R William Vandivier
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado Health Sciences Center, 4200 E. Ninth Avenue, C272, Denver, Colorado 80220, USA.
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Ottenheijm CAC, Heunks LMA, Li YP, Jin B, Minnaard R, van Hees HWH, Dekhuijzen PNR. Activation of the ubiquitin-proteasome pathway in the diaphragm in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2006; 174:997-1002. [PMID: 16917114 PMCID: PMC2648103 DOI: 10.1164/rccm.200605-721oc] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
RATIONALE Studies show that the myosin content of the diaphragm in patients with mild to moderate chronic obstructive pulmonary disease (COPD) is reduced, compromising diaphragm contractile performance. The mechanisms for reduced contractile protein content are unknown. In the present study we hypothesized that the loss of contractile protein content is associated with activation of the ubiquitin-proteasome pathway in the diaphragm of patients with mild to moderate COPD. METHODS Proteolytic activity of isolated 20S proteasomes was determined in diaphragm biopsies from patients with and without COPD (predicted mean FEV1, 66 and 93%, respectively). In addition, we determined 20S proteasome subunit C8 protein levels by means of Western blotting, ubiquitin-ligase mRNA levels by means of real-time polymerase chain reaction, and caspase-3 activity by determining the hydrolysis of fluorogenic substrates. RESULTS The 20S proteasome activity was about threefold increased in the diaphragm of patients with COPD. C8 protein levels were not significantly different between COPD and non-COPD diaphragm, indicating increased specific activity of individual proteasomes, rather than an increased number of proteasomes. mRNA levels of the muscle-specific ubiquitin-ligase MAFbx were significantly higher in diaphragm from patients with COPD compared with patients without COPD. Caspase-3-mediated cleavage of actomyosin complexes is considered an initial step in muscle wasting, yielding fragments that can be degraded by the ubiquitin-proteasome pathway. In line with the increased ubiquitin-proteasome activity, caspase-3 activity was higher in diaphragm homogenates from patients with COPD. CONCLUSIONS The present study is the first to demonstrate increased activity of the ubiquitin-proteasome pathway in COPD diaphragm. Importantly, these changes occur in patients with only mild to moderate COPD (Global Initiative for Chronic Obstructive Lung Disease stage I/II).
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Affiliation(s)
- Coen A C Ottenheijm
- Department of Pulmonary Diseases, 454, Radboud University Nijmegen Medical Center, 6500 HB Nijmegen, The Netherlands.
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Brissot R, Gonzalez-Bermejo J, Lassalle A, Desrues B, Doutrellot PL. Fatigue and respiratory disorders. ACTA ACUST UNITED AC 2006; 49:320-30, 403-12. [PMID: 16780993 DOI: 10.1016/j.annrmp.2006.04.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2006] [Accepted: 04/03/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVES To analyze the factors at the origin of fatigue in respiratory disorders. To assess fatigue and its functional impact on patients affected from respiratory diseases. To evaluate the results of comprehensive care on fatigue and functional capacity. MATERIALS AND METHODS We systematically reviewed the literature in Medline and the Cochrane Library, using the following keywords: fatigue, respiratory disorders, questionnaire, evaluation, assessment, randomized controlled trial, meta-analysis. RESULTS Fatigue is a high frequency symptom (90%) and takes an important place, as much as dyspnea, in the genesis of the respiratory induced handicap. Its assessment is varied, according to the studies. It originates from multiple causes, as shown from clinical and experimental studies. The main treatment consists in rehabilitation, using physical exercises. Its efficacy is demonstrated on physical endurance, but is not clear in terms of general fatigue. CONCLUSION Although fatigue is very frequent complaint, along with a major disabling condition, the comprehensive assessment of fatigue, in respiratory disorders, including its physical and cognitive components, is not still really codified. Rehabilitation is the main treatment. Its efficiency has been demonstrated on the physical and functional components of fatigue. Its results on perceived fatigue remains to be evaluated.
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Affiliation(s)
- R Brissot
- Service de Médecine Physique et de Réadaptation, Hôpital de Pontchaillou, CHU de Rennes, France.
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Yasuda H, Yamaya M, Nakayama K, Sasaki H. Blood Carbon Monoxide Will Increase from a Decline in Pulmonary Function Alone. Am J Respir Crit Care Med 2005. [DOI: 10.1164/ajrccm.172.9.956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Guerrero K, Wuyam B, Mezin P, Vivodtzev I, Vendelin M, Borel JC, Hacini R, Chavanon O, Imbeaud S, Saks V, Pison C. Functional coupling of adenine nucleotide translocase and mitochondrial creatine kinase is enhanced after exercise training in lung transplant skeletal muscle. Am J Physiol Regul Integr Comp Physiol 2005; 289:R1144-54. [PMID: 16020522 DOI: 10.1152/ajpregu.00229.2005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mechanisms responsible for limitation of exercise capacity in lung transplant recipients (LR) and benefits gained by exercise training were studied. Mitochondrial respiration parameters, energy transfer, and cell structure were assessed in vastus lateralis biopsies using the permeabilized fiber technique with histochemical and morphometric measurements. Twelve male controls (C) and 12 LR performed exercise training over 12 wk. Before exercise training, there were strong correlations between exercise capacity (maximal O2 consumption and endurance time at 70% maximal power output) and cellular events, as assessed by percentage of type I fibers and apparent Km for exogenous ADP. Anticalcineurins were not involved in LR exercise limitation, since there were no differences in maximal mitochondrial rate of respiration before exercise training and no abnormalities in respiratory chain complexes compared with C. Training resulted in a significant increase in physiological parameters both at the cellular (apparent Km for exogenous ADP and stimulating effect of creatine) and integrated (maximal O2 consumption, power output at ventilatory threshold, maximal power output, and endurance time at 70% maximal power output) levels in LR and C. After the training period, improvements in maximal O2 consumption and in maximal mitochondrial rate of respiration were noted, as well as changes in endurance time and percentage of type I fibers. Because there were no changes in diameters and fiber types, baseline alteration of apparent Km for exogenous ADP and its improvement after training might be related to changes within the intracellular energetic units. After the training period, intracellular energetic units exhibited a higher control of mitochondrial respiration by creatine linked to a more efficient functional coupling adenine nucleotide translocase-mitochondrial creatine kinase, resulting in better exercise performances in C and LR.
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Affiliation(s)
- Karen Guerrero
- Laboratoire de Bioénergétique Fondamentale et Appliquée, Institut National de la Santé et de la Recherche Médicale E221, Université Joseph Fourier, Grenoble, France
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Troosters T, Casaburi R, Gosselink R, Decramer M. Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease. Am J Respir Crit Care Med 2005; 172:19-38. [PMID: 15778487 DOI: 10.1164/rccm.200408-1109so] [Citation(s) in RCA: 295] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Thierry Troosters
- Respiratory Rehabilitation and Respiratory Division, UZ Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium.
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Yasuda H, Yamaya M, Nakayama K, Ebihara S, Sasaki T, Okinaga S, Inoue D, Asada M, Nemoto M, Sasaki H. Increased Arterial Carboxyhemoglobin Concentrations in Chronic Obstructive Pulmonary Disease. Am J Respir Crit Care Med 2005; 171:1246-51. [PMID: 15764730 DOI: 10.1164/rccm.200407-914oc] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Exhaled carbon monoxide (CO) and arterial blood carboxyhemoglobin concentrations (Hb-CO) increase in inflammatory pulmonary diseases. OBJECTIVES To study whether arterial Hb-CO is useful to monitor disease activity in patients with chronic obstructive pulmonary disease (COPD) who had stopped smoking. METHODS We measured arterial Hb-CO, arteriovenous Hb-CO differences, and FEV1 in 58 patients with COPD and 61 ex-smoking control subjects. RESULTS Arterial Hb-CO concentrations in patients at stable conditions were higher than those in control subjects (p < 0.0001). Furthermore, the Hb-CO concentrations in patients at the exacerbations (p < 0.0001) were higher than those at the stable conditions. Arterial Hb-CO concentrations in patients at stage III were higher than those in patients at stage II, and the Hb-CO concentrations in patients at stage IV were higher than those in patients at stage III at the stable conditions and exacerbations. Arterial Hb-CO correlated with exhaled CO in patients with COPD at stage II and stage III at the exacerbations. Arterial Hb-CO inversely correlated with the arterial blood partial oxygen pressure and FEV1. Arteriovenous Hb-CO differences in patients at the exacerbations did not differ from those in patients at stable conditions and from those in control subjects. Moreover, arterial Hb-CO correlated with serum C-reactive protein values and serum lipid peroxide concentrations. CONCLUSIONS These findings suggest that increased arterial Hb-CO may relate to severity in patients with COPD because of lung and systemic inflammation and production of reactive oxygen species.
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Affiliation(s)
- Hiroyasu Yasuda
- Department of Geriatric and Respiratory Medicine, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
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Barreiro E, de la Puente B, Minguella J, Corominas JM, Serrano S, Hussain SNA, Gea J. Oxidative Stress and Respiratory Muscle Dysfunction in Severe Chronic Obstructive Pulmonary Disease. Am J Respir Crit Care Med 2005; 171:1116-24. [PMID: 15735057 DOI: 10.1164/rccm.200407-887oc] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
RATIONALE Oxidative stress is involved in the skeletal muscle dysfunction observed in patients with severe chronic obstructive pulmonary disease (COPD). We hypothesized that the diaphragms of such patients might generate greater levels of oxidants than those neutralized by antioxidants. OBJECTIVES To assess the levels of both oxidative and nitrosative stress and different antioxidants in the diaphragms of those patients, and to analyze potential relationships with lung and respiratory muscle dysfunctions. METHODS AND MEASUREMENTS We conducted a case-control study in which reactive carbonyl groups, hydroxynonenal-protein adducts, antioxidant enzyme levels, nitric oxide synthases, and 3-nitrotyrosine formation were detected using immunoblotting and immunhistochemistry in diaphragm specimens (thoracotomy) obtained from six patients with severe COPD, six patients with moderate COPD, and seven control subjects. MAIN RESULTS Diaphragms of patients with severe COPD showed both higher protein carbonyl groups and hydroxynonenal-protein adducts than control subjects. When only considering patients with COPD, negative correlations were found between carbonyl groups and airway obstruction, and between hydroxynonenal-protein adducts and respiratory muscle strength. Although diaphragmatic neuronal nitric oxide synthase did not differ among the three groups and no inducible nitric oxide synthase was detected in any muscle, muscle endothelial nitric oxide synthase was lower in patients with severe COPD than in control subjects. Muscle nitrotyrosine levels were similar in both patients with severe COPD and control subjects. CONCLUSIONS This study shows that oxidative stress rather than nitric oxide is likely to be involved in the respiratory muscle dysfunction in severe COPD.
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Affiliation(s)
- Esther Barreiro
- Muscle and Respiratory System Research Unit, Respiratory Medicine Department, IMIM-Hospital del Mar, Universidad Pompeu Fabra, C/Dr. Aiguader, 80, E-08003 Barcelona, Spain.
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