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Arron HE, Marsh BD, Kell DB, Khan MA, Jaeger BR, Pretorius E. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: the biology of a neglected disease. Front Immunol 2024; 15:1386607. [PMID: 38887284 PMCID: PMC11180809 DOI: 10.3389/fimmu.2024.1386607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 04/11/2024] [Indexed: 06/20/2024] Open
Abstract
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a chronic, debilitating disease characterised by a wide range of symptoms that severely impact all aspects of life. Despite its significant prevalence, ME/CFS remains one of the most understudied and misunderstood conditions in modern medicine. ME/CFS lacks standardised diagnostic criteria owing to variations in both inclusion and exclusion criteria across different diagnostic guidelines, and furthermore, there are currently no effective treatments available. Moving beyond the traditional fragmented perspectives that have limited our understanding and management of the disease, our analysis of current information on ME/CFS represents a significant paradigm shift by synthesising the disease's multifactorial origins into a cohesive model. We discuss how ME/CFS emerges from an intricate web of genetic vulnerabilities and environmental triggers, notably viral infections, leading to a complex series of pathological responses including immune dysregulation, chronic inflammation, gut dysbiosis, and metabolic disturbances. This comprehensive model not only advances our understanding of ME/CFS's pathophysiology but also opens new avenues for research and potential therapeutic strategies. By integrating these disparate elements, our work emphasises the necessity of a holistic approach to diagnosing, researching, and treating ME/CFS, urging the scientific community to reconsider the disease's complexity and the multifaceted approach required for its study and management.
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Affiliation(s)
- Hayley E. Arron
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Benjamin D. Marsh
- MRCPCH Consultant Paediatric Neurodisability, Exeter, Devon, United Kingdom
| | - Douglas B. Kell
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
- The Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - M. Asad Khan
- Directorate of Respiratory Medicine, Manchester University Hospitals, Wythenshawe Hospital, Manchester, United Kingdom
| | - Beate R. Jaeger
- Long COVID department, Clinic St Georg, Bad Aibling, Germany
| | - Etheresia Pretorius
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
- Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
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Fonseca A, Szysz M, Ly HT, Cordeiro C, Sepúlveda N. IgG Antibody Responses to Epstein-Barr Virus in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Their Effective Potential for Disease Diagnosis and Pathological Antigenic Mimicry. MEDICINA (KAUNAS, LITHUANIA) 2024; 60:161. [PMID: 38256421 PMCID: PMC10820613 DOI: 10.3390/medicina60010161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/02/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024]
Abstract
Background and Objectives: The diagnosis and pathology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) remain under debate. However, there is a growing body of evidence for an autoimmune component in ME/CFS caused by the Epstein-Barr virus (EBV) and other viral infections. Materials and Methods: In this work, we analyzed a large public dataset on the IgG antibodies to 3054 EBV peptides to understand whether these immune responses could help diagnose patients and trigger pathological autoimmunity; we used healthy controls (HCs) as a comparator cohort. Subsequently, we aimed at predicting the disease status of the study participants using a super learner algorithm targeting an accuracy of 85% when splitting data into train and test datasets. Results: When we compared the data of all ME/CFS patients or the data of a subgroup of those patients with non-infectious or unknown disease triggers to the data of the HC, we could not find an antibody-based classifier that would meet the desired accuracy in the test dataset. However, we could identify a 26-antibody classifier that could distinguish ME/CFS patients with an infectious disease trigger from the HCs with 100% and 90% accuracies in the train and test sets, respectively. We finally performed a bioinformatic analysis of the EBV peptides associated with these 26 antibodies. We found no correlation between the importance metric of the selected antibodies in the classifier and the maximal sequence homology between human proteins and each EBV peptide recognized by these antibodies. Conclusions: In conclusion, these 26 antibodies against EBV have an effective potential for disease diagnosis in a subset of patients. However, the peptides associated with these antibodies are less likely to induce autoimmune B-cell responses that could explain the pathogenesis of ME/CFS.
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Affiliation(s)
- André Fonseca
- Faculty of Sciences and Technology, University of Algarve, 8005-139 Faro, Portugal; (A.F.); (C.C.)
- CEAUL—Centre of Statistics and its Applications, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Mateusz Szysz
- Faculty of Mathematics & Information Science, Warsaw University of Technology, 00-662 Warsaw, Poland; (M.S.); (H.T.L.)
| | - Hoang Thien Ly
- Faculty of Mathematics & Information Science, Warsaw University of Technology, 00-662 Warsaw, Poland; (M.S.); (H.T.L.)
| | - Clara Cordeiro
- Faculty of Sciences and Technology, University of Algarve, 8005-139 Faro, Portugal; (A.F.); (C.C.)
- CEAUL—Centre of Statistics and its Applications, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Nuno Sepúlveda
- CEAUL—Centre of Statistics and its Applications, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
- Faculty of Mathematics & Information Science, Warsaw University of Technology, 00-662 Warsaw, Poland; (M.S.); (H.T.L.)
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3
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Kaczmarek MP. Heterogenous circulating miRNA changes in ME/CFS converge on a unified cluster of target genes: A computational analysis. PLoS One 2023; 18:e0296060. [PMID: 38157384 PMCID: PMC10756525 DOI: 10.1371/journal.pone.0296060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 12/02/2023] [Indexed: 01/03/2024] Open
Abstract
Myalgic Encephalomyelitis / Chronic Fatigue Syndrome is a debilitating, multisystem disease of unknown mechanism, with a currently ongoing search for its endocrine mediators. Circulating microRNAs (miRNA) are a promising candidate for such a mediator and have been reported as significantly different in the patient population versus healthy controls by multiple studies. None of these studies, however, agree with each other on which specific miRNA are under- or over-expressed. This discrepancy is the subject of the computational study presented here, in which a deep dive into the predicted gene targets and their functional interactions is conducted, revealing that the aberrant circulating miRNAs in ME/CFS, although different between patients, seem to mainly target the same specific set of genes (p ≈ 0.0018), which are very functionally related to each other (p ≲ 0.0001). Further analysis of these functional relations, based on directional pathway information, points to impairments in exercise hyperemia, angiogenic adaptations to hypoxia, antioxidant defenses, and TGF-β signaling, as well as a shift towards mitochondrial fission, corroborating and explaining previous direct observations in ME/CFS. Many transcription factors and epigenetic modulators are implicated as well, with currently uncertain downstream combinatory effects. As the results show significant similarity to previous research on latent herpesvirus involvement in ME/CFS, the possibility of a herpesvirus origin of these miRNA changes is also explored through further computational analysis and literature review, showing that 8 out of the 10 most central miRNAs analyzed are known to be upregulated by various herpesviruses. In total, the results establish an appreciable and possibly central role for circulating microRNAs in ME/CFS etiology that merits further experimental research.
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Raizen DM, Mullington J, Anaclet C, Clarke G, Critchley H, Dantzer R, Davis R, Drew KL, Fessel J, Fuller PM, Gibson EM, Harrington M, Ian Lipkin W, Klerman EB, Klimas N, Komaroff AL, Koroshetz W, Krupp L, Kuppuswamy A, Lasselin J, Lewis LD, Magistretti PJ, Matos HY, Miaskowski C, Miller AH, Nath A, Nedergaard M, Opp MR, Ritchie MD, Rogulja D, Rolls A, Salamone JD, Saper C, Whittemore V, Wylie G, Younger J, Zee PC, Craig Heller H. Beyond the symptom: the biology of fatigue. Sleep 2023; 46:zsad069. [PMID: 37224457 PMCID: PMC10485572 DOI: 10.1093/sleep/zsad069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/24/2023] [Indexed: 05/26/2023] Open
Abstract
A workshop titled "Beyond the Symptom: The Biology of Fatigue" was held virtually September 27-28, 2021. It was jointly organized by the Sleep Research Society and the Neurobiology of Fatigue Working Group of the NIH Blueprint Neuroscience Research Program. For access to the presentations and video recordings, see: https://neuroscienceblueprint.nih.gov/about/event/beyond-symptom-biology-fatigue. The goals of this workshop were to bring together clinicians and scientists who use a variety of research approaches to understand fatigue in multiple conditions and to identify key gaps in our understanding of the biology of fatigue. This workshop summary distills key issues discussed in this workshop and provides a list of promising directions for future research on this topic. We do not attempt to provide a comprehensive review of the state of our understanding of fatigue, nor to provide a comprehensive reprise of the many excellent presentations. Rather, our goal is to highlight key advances and to focus on questions and future approaches to answering them.
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Affiliation(s)
- David M Raizen
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Janet Mullington
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Christelle Anaclet
- Department of Neurological Surgery, University of California, Davis School of Medicine, Sacramento, CA, USA
| | - Gerard Clarke
- Department of Psychiatry and Neurobehavioural Science, and APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Hugo Critchley
- Brighton and Sussex Medical School Department of Neuroscience, University of Sussex, Brighton, UK
| | - Robert Dantzer
- Department of Symptom Research, Division of Internal Medicine, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ronald Davis
- Department of Biochemistry and Genetics, Stanford University, Palo Alto, CA, USA
| | - Kelly L Drew
- Department of Chemistry and Biochemistry, Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Josh Fessel
- Division of Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Patrick M Fuller
- Department of Neurological Surgery, University of California, Davis School of Medicine, Sacramento, CA, USA
| | - Erin M Gibson
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA, USA
| | - Mary Harrington
- Department of Psychology, Neuroscience Program, Smith College, Northampton, MA, USA
| | - W Ian Lipkin
- Center for Infection and Immunity, and Departments of Neurology and Pathology, Columbia University, New York City, NY, USA
| | - Elizabeth B Klerman
- Division of Sleep Medicine, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Nancy Klimas
- Department of Clinical Immunology, College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA
| | - Anthony L Komaroff
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Walter Koroshetz
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Lauren Krupp
- Department of Neurology, NYU Grossman School of Medicine, NYC, NY, USA
| | - Anna Kuppuswamy
- University College London, Queen Square Institute of Neurology, London, England
| | - Julie Lasselin
- Department of Psychology, Stockholm University, Stockholm, Sweden
| | - Laura D Lewis
- Center for Systems Neuroscience, Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - Pierre J Magistretti
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Kingdom of Saudi Arabia
| | - Heidi Y Matos
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Christine Miaskowski
- Department of Physiological Nursing, School of Nursing, University of California, San Francisco, CA, USA
| | - Andrew H Miller
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Avindra Nath
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Maiken Nedergaard
- Departments of Neurology and Neurosurgery, University of Rochester Medical Center, Rochester, NY, USA
| | - Mark R Opp
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Marylyn D Ritchie
- Department of Genetics, Institute for Biomedical Informatics, Penn Center for Precision Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dragana Rogulja
- Department of Neurobiology, Harvard University, Boston, MA, USA
| | - Asya Rolls
- Rappaport Institute for Medical Research, Technion, Israel Institute of Technology, Haifa, Israel
| | - John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
| | - Clifford Saper
- Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Vicky Whittemore
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Glenn Wylie
- Rocco Ortenzio Neuroimaging Center at Kessler Foundation, East Hanover, NJ, USA
| | - Jarred Younger
- Department of Psychology, University of Alabama, Birmingham, Birmingham, AL, USA
| | - Phyllis C Zee
- Center for Circadian and Sleep Medicine, Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - H Craig Heller
- Department of Biology, Stanford University and Sleep Research Society, Stanford, CA, USA
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5
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Maya J. Surveying the Metabolic and Dysfunctional Profiles of T Cells and NK Cells in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Int J Mol Sci 2023; 24:11937. [PMID: 37569313 PMCID: PMC10418326 DOI: 10.3390/ijms241511937] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 08/13/2023] Open
Abstract
Millions globally suffer from myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The inflammatory symptoms, illness onset, recorded outbreak events, and physiological variations provide strong indications that ME/CFS, at least sometimes, has an infectious origin, possibly resulting in a chronic unidentified viral infection. Meanwhile, studies exposing generalized metabolic disruptions in ME/CFS have stimulated interest in isolated immune cells with an altered metabolic state. As the metabolism dictates the cellular function, dissecting the biomechanics of dysfunctional immune cells in ME/CFS can uncover states such as exhaustion, senescence, or anergy, providing insights into the consequences of these phenotypes in this disease. Despite the similarities that are seen metabolically between ME/CFS and other chronic viral infections that result in an exhausted immune cell state, immune cell exhaustion has not yet been verified in ME/CFS. This review explores the evidence for immunometabolic dysfunction in ME/CFS T cell and natural killer (NK) cell populations, comparing ME/CFS metabolic and functional features to dysfunctional immune cell states, and positing whether anergy, exhaustion, or senescence could be occurring in distinct immune cell populations in ME/CFS, which is consistent with the hypothesis that ME/CFS is a chronic viral disease. This comprehensive review of the ME/CFS immunometabolic literature identifies CD8+ T cell exhaustion as a probable contender, underscores the need for further investigation into the dysfunctional state of CD4+ T cells and NK cells, and explores the functional implications of molecular findings in these immune-cell types. Comprehending the cause and impact of ME/CFS immune cell dysfunction is critical to understanding the physiological mechanisms of ME/CFS, and developing effective treatments to alleviate the burden of this disabling condition.
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Affiliation(s)
- Jessica Maya
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14850, USA
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6
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Kamamuta A, Takagi Y, Takahashi M, Kurihara K, Shibata H, Tanaka K, Hata K. Fatigue Potentially Reduces the Effect of Transcranial Magnetic Stimulation on Depression Following COVID-19 and Its Vaccination. Vaccines (Basel) 2023; 11:1151. [PMID: 37514967 PMCID: PMC10383898 DOI: 10.3390/vaccines11071151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/17/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
COVID-19's long-term effects, known as Long-COVID, present psychiatric and physical challenges in recovered patients. Similarly, rare long-term post-vaccination side effects, resembling Long-COVID, are emerging (called Post-Vaccine). However, effective treatments for both conditions are scarce. Our clinical experience suggests that transcranial magnetic stimulation (TMS) often aids recovery in Long-COVID and Post-Vaccine patients. However, its effectiveness is reduced in patients with severe fatigue. Therefore, we retrospectively analysed Tokyo TMS Clinic's outpatient records (60 in total; mean age, 38 years) to compare Long-COVID and post-vaccine patients' characteristics and symptoms, assess the impact of TMS on their symptoms, and investigate the role of fatigue in depression recovery with TMS. The primary outcome was the regression coefficient of the initial fatigue score on depression score improvement using TMS. Secondary outcomes included psychiatric/physical scores before and after TMS and their improvement rates. We found no differences in the initial symptoms and background factors between Long-COVID and Post-Vaccine patients. After ten TMS sessions, all psychiatric and physical symptom scores improved significantly. TMS improves depression, insomnia, anxiety, and related neuropsychiatric symptoms, which were the primary complaints in this study. Thus, we conclude that TMS improves depression and anxiety. The effectiveness of TMS in treating depression in Long-COVID and Post-Vaccine patients decreased as fatigue severity increased. In conclusion, TMS relieved depressive symptoms following COVID-19 and vaccination; however, fatigue may hinder its effectiveness.
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Affiliation(s)
| | | | | | | | | | | | - Katsuhiko Hata
- Tokyo TMS Clinic, Tokyo 150-0021, Japan
- Department of Physics, Tokyo University of Science, Tokyo 162-8601, Japan
- Department of Neuroscience, Research Center for Mathematical Medicine, Tokyo 183-0014, Japan
- Department of Sports and Medical Science, Graduate School of Emergency Medical System, Kokushikan University, Tokyo 206-8515, Japan
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7
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Retornaz F, Rebaudet S, Stavris C, Jammes Y. Long-term neuromuscular consequences of SARS-Cov-2 and their similarities with myalgic encephalomyelitis/chronic fatigue syndrome: results of the retrospective CoLGEM study. Lab Invest 2022; 20:429. [PMID: 36153556 PMCID: PMC9509619 DOI: 10.1186/s12967-022-03638-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 09/13/2022] [Indexed: 11/10/2022]
Abstract
Abstract
Background
Patients with long-COVID often complain of continuous fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise. No data are available on EMG recording of evoked myopotentials (M-waves) or exercise-induced alterations in long-COVID patients, providing evidence of muscle membrane fatigue. Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) develops in more than half of patients after an infectious disease, particularly viral diseases. A large proportion (around 70%) of these patients have neuromuscular disorders with M-wave alterations during and after exercise. Our hypothesis was that M-wave alterations would be also found in long-COVID patients, in association with neuromuscular symptoms, similar to ME/CFS.
Methods
This retrospective observational ColGEM (Covid LonG Encéphalomyelite Myalgique) study compared 59 patients with long-COVID and 55 ME/CFS patients with a history of severe infection who presented before the COVID pandemic. All of these patients underwent the same protocol consisting of a questionnaire focusing on neural and neuromuscular disorders and M-wave recording in the rectus femoris muscle before, during, and 10 min after a progressive cycling exercise. Maximal handgrip strength (MHGS) and maximal exercise power were also measured. The frequency of symptoms and magnitude of M-wave changes in the two groups were compared using non-parametric and parametric tests.
Results
The frequency of fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise as well as the magnitude of exercise-induced M-wave alterations were the same in the two groups. By contrast, digestive problems were less present in long-COVID. M-wave alterations were greater in ME/CFS patients as in those with long-COVID when the highest muscle strength and highest exercise performance were measured.
Conclusions
These high clinical and biological similarities between long-COVID and ME/CFS support the hypothesis that SARS-Cov-2 infection can cause ME/CFS symptoms.
Trial registration Registered retrospectively.
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Lv Y, Zhang T, Cai J, Huang C, Zhan S, Liu J. Bioinformatics and systems biology approach to identify the pathogenetic link of Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Front Immunol 2022; 13:952987. [PMID: 36189286 PMCID: PMC9524193 DOI: 10.3389/fimmu.2022.952987] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 08/18/2022] [Indexed: 11/13/2022] Open
Abstract
Background The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global crisis. Although many people recover from COVID-19 infection, they are likely to develop persistent symptoms similar to those of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) after discharge. Those constellations of symptoms persist for months after infection, called Long COVID, which may lead to considerable financial burden and healthcare challenges. However, the mechanisms underlying Long COVID and ME/CFS remain unclear. Methods We collected the genes associated with Long COVID and ME/CFS in databases by restricted screening conditions and clinical sample datasets with limited filters. The common genes for Long COVID and ME/CFS were finally obtained by taking the intersection. We performed several advanced bioinformatics analyses based on common genes, including gene ontology and pathway enrichment analyses, protein–protein interaction (PPI) analysis, transcription factor (TF)–gene interaction network analysis, transcription factor–miRNA co-regulatory network analysis, and candidate drug analysis prediction. Results We found nine common genes between Long COVID and ME/CFS and gained a piece of detailed information on their biological functions and signaling pathways through enrichment analysis. Five hub proteins (IL-6, IL-1B, CD8A, TP53, and CXCL8) were collected by the PPI network. The TF–gene and TF–miRNA coregulatory networks were demonstrated by NetworkAnalyst. In the end, 10 potential chemical compounds were predicted. Conclusion This study revealed common gene interaction networks of Long COVID and ME/CFS and predicted potential therapeutic drugs for clinical practice. Our findings help to identify the potential biological mechanism between Long COVID and ME/CFS. However, more laboratory and multicenter evidence is required to explore greater mechanistic insight before clinical application in the future.
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Affiliation(s)
- Yongbiao Lv
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Tian Zhang
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Junxiang Cai
- Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
| | - Chushuan Huang
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shaofeng Zhan
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jianbo Liu
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
- *Correspondence: Jianbo Liu,
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9
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The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications. Biochem J 2022; 479:1653-1708. [PMID: 36043493 PMCID: PMC9484810 DOI: 10.1042/bcj20220154] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 02/07/2023]
Abstract
Ischaemia–reperfusion (I–R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I–R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.
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10
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Filippi M, Krähenmann R, Fissler P. The Link Between Energy-Related Sensations and Metabolism: Implications for Treating Fatigue. Front Psychol 2022; 13:920556. [PMID: 35800955 PMCID: PMC9255916 DOI: 10.3389/fpsyg.2022.920556] [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: 04/14/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Energy-related sensations include sensation of energy and fatigue as well as subjective energizability and fatigability. First, we introduce interdisciplinary useful definitions of all constructs and review findings regarding the question of whether sensations of fatigue and energy are two separate constructs or two ends of a single dimension. Second, we describe different components of the bodily energy metabolism system (e.g., mitochondria; autonomic nervous system). Third, we review the link between sensation of fatigue and different components of energy metabolism. Finally, we present an overview of different treatments shown to affect both energy-related sensations and metabolism before outlining future research perspectives.
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Affiliation(s)
- Marco Filippi
- Psychiatric Services Thurgau, Münsterlingen, Switzerland
- University Hospital for Psychiatry and Psychotherapy, Paracelsus Medical University, Salzburg, Austria
| | - Rainer Krähenmann
- Psychiatric Services Thurgau, Münsterlingen, Switzerland
- University Hospital for Psychiatry and Psychotherapy, Paracelsus Medical University, Salzburg, Austria
- Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zürich, Zürich, Switzerland
- *Correspondence: Rainer Krähenmann,
| | - Patrick Fissler
- Psychiatric Services Thurgau, Münsterlingen, Switzerland
- University Hospital for Psychiatry and Psychotherapy, Paracelsus Medical University, Salzburg, Austria
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11
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Stanculescu D, Sepúlveda N, Lim CL, Bergquist J. Lessons From Heat Stroke for Understanding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Front Neurol 2021; 12:789784. [PMID: 34966354 PMCID: PMC8710546 DOI: 10.3389/fneur.2021.789784] [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: 10/05/2021] [Accepted: 11/11/2021] [Indexed: 01/01/2023] Open
Abstract
We here provide an overview of the pathophysiological mechanisms during heat stroke and describe similar mechanisms found in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Both conditions are characterized by disturbed homeostasis in which inflammatory pathways play a central role. Splanchnic vasoconstriction, increased gut permeability, gut-related endotoxemia, systemic inflammatory response, central nervous system dysfunction, blood coagulation disorder, endothelial-cell injury, and mitochondrial dysfunction underlie heat stroke. These mechanisms have also been documented in ME/CFS. Moreover, initial transcriptomic studies suggest that similar gene expressions are altered in both heat stroke and ME/CFS. Finally, some predisposing factors for heat stroke, such as pre-existing inflammation or infection, overlap with those for ME/CFS. Notwithstanding important differences - and despite heat stroke being an acute condition - the overlaps between heat stroke and ME/CFS suggest common pathways in the physiological responses to very different forms of stressors, which are manifested in different clinical outcomes. The human studies and animal models of heat stroke provide an explanation for the self-perpetuation of homeostatic imbalance centered around intestinal wall injury, which could also inform the understanding of ME/CFS. Moreover, the studies of novel therapeutics for heat stroke might provide new avenues for the treatment of ME/CFS. Future research should be conducted to investigate the similarities between heat stroke and ME/CFS to help identify the potential treatments for ME/CFS.
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Affiliation(s)
| | - Nuno Sepúlveda
- CEAUL-Centro de Estatística e Aplicações da Universidade de Lisboa, Lisbon, Portugal.,Department of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland
| | - Chin Leong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Jonas Bergquist
- Analytical Chemistry and Neurochemistry, Department of Chemistry-BMC, Uppsala University, Uppsala, Sweden.,The ME/CFS Collaborative Research Center at Uppsala University, Uppsala, Sweden
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12
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Trautmann A. [Mechanisms underlying chronic fatigue, a symptom too often overlooked]. Med Sci (Paris) 2021; 37:910-919. [PMID: 34647880 DOI: 10.1051/medsci/2021143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Acute fatigue after exertion, like acute inflammation after injury, is useful for our body. On the contrary, both chronic fatigue and chronic inflammation are deleterious, and they are associated in many diseases. In this first part, we will analyze different immune phenomena (bystander activation, memory of the innate immune system, link with the intestinal microbiota) involved in triggering chronic inflammation. This review aims at looking for links between different signs and symptoms associated with chronic fatigue, as well as between different diseases in which severe chronic fatigue can manifest. Possible underlying mechanisms for these phenomena are discussed. This is a proposal made by a researcher, with no clinical experience, to doctors confronted with an entity that is still largely mysterious. The link between chronic inflammation, neuroinflammation and fatigue will be examined in a second part.
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Affiliation(s)
- Alain Trautmann
- UMR CNRS 8104, Inserm 1016, université Paris Descartes, Institut Cochin, rue Méchain, 75014 Paris, France
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13
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Weigel B, Eaton-Fitch N, Passmore R, Cabanas H, Staines D, Marshall-Gradisnik S. A preliminary investigation of nutritional intake and supplement use in Australians with myalgic encephalomyelitis/chronic fatigue syndrome and the implications on health-related quality of life. Food Nutr Res 2021; 65:5730. [PMID: 34262415 PMCID: PMC8254462 DOI: 10.29219/fnr.v65.5730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/01/2021] [Accepted: 04/02/2021] [Indexed: 01/08/2023] Open
Abstract
Background Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, multisystem illness without a currently recognized pharmacological treatment. Dietary supplementation and modification have been posited as potential management strategies; however, their efficacy is controversial. Objective This study aimed to assess the nutritional intake and supplement use of Australian ME/CFS patients and the perceived effect on health-related quality of life (HRQoL) for the first time in an Australian patient population. Design Between February 2019 and January 2020, ME/CFS patients across Australia volunteered in this cross-sectional study in response to online advertisements. Eligible respondents were invited to complete three online self-administered questionnaires investigating their supplement use, nutritional intake, and HRQoL. The study participants’ supplement use and nutritional intake were summarized and compared with the population data returned from the Australian Health Survey (2011–2012). Multiple linear regression analysis was also performed to determine the effect of participants’ supplement use and nutrient intake on HRQoL. Results Twenty-four eligible ME/CFS patients (54.2% meeting the International Consensus Criteria, 79.2% female, mean age = 43.4 ± 10.5 years) completed the online questionnaires. Supplement use was highly prevalent among the study sample (87.5%) and considerably more common when compared with population data (31.9%). Daily total fats and caffeine intakes were significantly higher among ME/CFS patients when compared with the Australian population (P = 0.009 and P = 0.033, respectively), whereas daily intakes of total carbohydrates and alcohol were significantly lower (both P < 0.001). No consistent trends between nutrition and supplement use with patients’ HRQoL could be identified. Conclusions The daily diet and supplement use of ME/CFS patients appear to vary considerably from those of the general Australian population. Although the role of nutritional intake and supplement use on ME/CFS patients’ HRQoL remains unclear, dietary changes and the use of supplements appear to be of value to ME/CFS patients.
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Affiliation(s)
- Breanna Weigel
- The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Consortium Health International for Myalgic Encephalomyelitis, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,School of Medical Science, Griffith University, Gold Coast, Australia
| | - Natalie Eaton-Fitch
- The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Consortium Health International for Myalgic Encephalomyelitis, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,School of Medical Science, Griffith University, Gold Coast, Australia
| | - Rachel Passmore
- The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Consortium Health International for Myalgic Encephalomyelitis, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,School of Medical Science, Griffith University, Gold Coast, Australia
| | - Hélène Cabanas
- The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Consortium Health International for Myalgic Encephalomyelitis, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,School of Medical Science, Griffith University, Gold Coast, Australia
| | - Donald Staines
- The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Consortium Health International for Myalgic Encephalomyelitis, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
| | - Sonya Marshall-Gradisnik
- The National Centre for Neuroimmunology and Emerging Diseases, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Consortium Health International for Myalgic Encephalomyelitis, Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
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Stanculescu D, Larsson L, Bergquist J. Theory: Treatments for Prolonged ICU Patients May Provide New Therapeutic Avenues for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Front Med (Lausanne) 2021; 8:672370. [PMID: 34026797 PMCID: PMC8137963 DOI: 10.3389/fmed.2021.672370] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/01/2021] [Indexed: 12/20/2022] Open
Abstract
We here provide an overview of treatment trials for prolonged intensive care unit (ICU) patients and theorize about their relevance for potential treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these treatment trials generally target: (a) the correction of suppressed endocrine axes, notably through a "reactivation" of the pituitary gland's pulsatile secretion of tropic hormones, or (b) the interruption of the "vicious circle" between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function. There are significant parallels in the treatment trials for prolonged critical illness and ME/CFS; this is consistent with the hypothesis of an overlap in the mechanisms that prevent recovery in both conditions. Early successes in the simultaneous reactivation of pulsatile pituitary secretions in ICU patients-and the resulting positive metabolic effects-could indicate an avenue for treating ME/CFS. The therapeutic effects of thyroid hormones-including in mitigating O&NS and inflammation and in stimulating the adreno-cortical axis-also merit further studies. Collaborative research projects should further investigate the lessons from treatment trials for prolonged critical illness for solving ME/CFS.
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Affiliation(s)
| | - Lars Larsson
- Basic and Clinical Muscle Biology, Department of Physiology and Pharmacology, Karolinska Institute, Solna, Sweden
| | - Jonas Bergquist
- Analytical Chemistry and Neurochemistry, Department of Chemistry–Biomedical Center, Uppsala University, Uppsala, Sweden
- The Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Collaborative Research Centre at Uppsala University, Uppsala, Sweden
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15
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The Interplay between Oxidative Stress, Exercise, and Pain in Health and Disease: Potential Role of Autonomic Regulation and Epigenetic Mechanisms. Antioxidants (Basel) 2020; 9:antiox9111166. [PMID: 33238564 PMCID: PMC7700330 DOI: 10.3390/antiox9111166] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/20/2020] [Accepted: 11/21/2020] [Indexed: 02/07/2023] Open
Abstract
Oxidative stress can be induced by various stimuli and altered in certain conditions, including exercise and pain. Although many studies have investigated oxidative stress in relation to either exercise or pain, the literature presents conflicting results. Therefore, this review critically discusses existing literature about this topic, aiming to provide a clear overview of known interactions between oxidative stress, exercise, and pain in healthy people as well as in people with chronic pain, and to highlight possible confounding factors to keep in mind when reflecting on these interactions. In addition, autonomic regulation and epigenetic mechanisms are proposed as potential mechanisms of action underlying the interplay between oxidative stress, exercise, and pain. This review highlights that the relation between oxidative stress, exercise, and pain is poorly understood and not straightforward, as it is dependent on the characteristics of exercise, but also on which population is investigated. To be able to compare studies on this topic, strict guidelines should be developed to limit the effect of several confounding factors. This way, the true interplay between oxidative stress, exercise, and pain, and the underlying mechanisms of action can be revealed and validated via independent studies.
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16
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Role of mitochondria, oxidative stress and the response to antioxidants in myalgic encephalomyelitis/chronic fatigue syndrome: A possible approach to SARS-CoV-2 'long-haulers'? Chronic Dis Transl Med 2020; 7:14-26. [PMID: 33251031 PMCID: PMC7680046 DOI: 10.1016/j.cdtm.2020.11.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Indexed: 12/12/2022] Open
Abstract
A significant number of SARS-CoV-2 (COVID-19) pandemic patients have developed chronic symptoms lasting weeks or months which are very similar to those described for myalgic encephalomyelitis/chronic fatigue syndrome. This study reviews the current literature and understanding of the role that mitochondria, oxidative stress and antioxidants may play in the understanding of the pathophysiology and treatment of chronic fatigue. It describes what is known about the dysfunctional pathways which can develop in mitochondria and their relationship to chronic fatigue. It also reviews what is known about oxidative stress and how this can be related to the pathophysiology of fatigue, as well as examining the potential for specific therapy directed at mitochondria for the treatment of chronic fatigue in the form of antioxidants. This study identifies areas which require urgent, further research in order to fully elucidate the clinical and therapeutic potential of these approaches.
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17
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Increased Oxidative Stress in Injured and Ill Elite International Olympic Rowers. Int J Sports Physiol Perform 2020; 15:625-631. [PMID: 32000137 DOI: 10.1123/ijspp.2019-0425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/25/2019] [Accepted: 08/01/2019] [Indexed: 11/18/2022]
Abstract
BACKGROUND Identifying strategies that reduce the risk of illness and injury is an objective of sports science and medicine teams. No studies have examined the relationship between oxidative stress (OS) and illness or injury in international athletes undergoing periods of intensified training and competition. PURPOSE The authors aimed to identify relationships between illness, injury, and OS. METHODS A longitudinal, observational study of elite male rowers (n = 10) was conducted over 18 weeks, leading into World Championships. Following a recovery day and a 12-hour fast, hydroperoxides (free oxygen radicals test) and total antioxidant capacity (free oxygen radicals defense) were measured in venous blood, with the ratio calculated as the oxidative stress index (OSI). At all study time points, athletes were independently dichotomized as ill or not ill, injured or not injured. OS data were compared between groups using independent t tests. A Cox proportional hazard model was used to assess the association of OS with injury and illness while adjusting for age and body mass index. RESULTS Free oxygen radicals defense was lower (P < .02) and OSI was higher (P < .001) with illness than without illness. Free oxygen radicals test and OSI were higher with injury than without injury (P < .001). A 0.5 mmol·L-1 increase in free oxygen radicals defense was associated with a 30.6% illness risk reduction (95% confidence interval, 7%-48%, P = .014), whereas 0.5 unit increase in OSI was related to a 11.3% increased illness risk (95% confidence interval, 1%-23%, P = .036). CONCLUSIONS OS is increased in injured and ill athletes. Monitoring OS may be advantageous in assessing recovery from and in reducing injury and illness risk given the association.
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18
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Jammes Y, Adjriou N, Kipson N, Criado C, Charpin C, Rebaudet S, Stavris C, Guieu R, Fenouillet E, Retornaz F. Altered muscle membrane potential and redox status differentiates two subgroups of patients with chronic fatigue syndrome. J Transl Med 2020; 18:173. [PMID: 32306967 PMCID: PMC7168976 DOI: 10.1186/s12967-020-02341-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 04/09/2020] [Indexed: 12/31/2022] Open
Abstract
Background In myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), altered membrane excitability often occurs in exercising muscles demonstrating muscle dysfunction regardless of any psychiatric disorder. Increased oxidative stress is also present in many ME/CFS patients and could affect the membrane excitability of resting muscles. Methods Seventy-two patients were examined at rest, during an incremental cycling exercise and during a 10-min post-exercise recovery period. All patients had at least four criteria leading to a diagnosis of ME/CFS. To explore muscle membrane excitability, M-waves were recorded during exercise (rectus femoris (RF) muscle) and at rest (flexor digitorum longus (FDL) muscle). Two plasma markers of oxidative stress (thiobarbituric acid reactive substance (TBARS) and oxidation–reduction potential (ORP)) were measured. Plasma potassium (K+) concentration was also measured at rest and at the end of exercise to explore K+ outflow. Results Thirty-nine patients had marked M-wave alterations in both the RF and FDL muscles during and after exercise while the resting values of plasma TBARS and ORP were increased and exercise-induced K+ outflow was decreased. In contrast, 33 other patients with a diagnosis of ME/CFS had no M-wave alterations and had lower baseline levels of TBARS and ORP. M-wave changes were inversely proportional to TBARS and ORP levels. Conclusions Resting muscles of ME/CFS patients have altered muscle membrane excitability. However, our data reveal heterogeneity in some major biomarkers in ME/CFS patients. Measurement of ORP may help to improve the diagnosis of ME/CFS. Trial registration Ethics Committee “Ouest II” of Angers (May 17, 2019) RCB ID: number 2019-A00611-56
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Affiliation(s)
- Yves Jammes
- UMR 1263 C2VN INRA INSERM, Faculty of Medicine, Aix Marseille University, Marseille, France.,Department of Internal Medicine, European Hospital, Marseille, France
| | - Nabil Adjriou
- UMR 1263 C2VN INRA INSERM, Faculty of Medicine, Aix Marseille University, Marseille, France
| | - Nathalie Kipson
- UMR 1263 C2VN INRA INSERM, Faculty of Medicine, Aix Marseille University, Marseille, France
| | - Christine Criado
- UMR 1263 C2VN INRA INSERM, Faculty of Medicine, Aix Marseille University, Marseille, France
| | - Caroline Charpin
- Department of Internal Medicine, European Hospital, Marseille, France
| | | | - Chloé Stavris
- Department of Internal Medicine, European Hospital, Marseille, France
| | - Régis Guieu
- UMR 1263 C2VN INRA INSERM, Faculty of Medicine, Aix Marseille University, Marseille, France
| | - Emmanuel Fenouillet
- UMR 1263 C2VN INRA INSERM, Faculty of Medicine, Aix Marseille University, Marseille, France.,Institut National des Sciences Biologiques, CNRS, Paris, France
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19
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Abstract
Muscle failure has been demonstrated in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Neurophysiological tools demonstrate the existence of both central and peripheral fatigue in these patients. Central fatigue is deduced from the reduced amplitude of myopotentials evoked by transcranial magnetic stimulation of the motor cortex as well as by the muscle response to interpolated twitches during sustained fatiguing efforts. An impaired muscle membrane conduction velocity assessed by the reduced amplitude and lengthened duration of myopotentials evoked by direct muscle stimulation is the defining feature of peripheral fatigue. Some patients with ME/CFS show an increased oxidative stress response to exercise. The formation of lipid hydroperoxides in the sarcolemma, which alters ionic fluxes, could explain the reduction of muscle membrane excitability and potassium outflow often measured in these patients. In patients with ME/CFS, the formation of heat shock proteins (HSPs) is also reduced. Because HSPs protect muscle cells against the deleterious effects of reactive oxygen species, the lack of their production could explain the augmented oxidative stress and the consecutive alterations of myopotentials which could open a way for future treatment of ME/CFS.
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Affiliation(s)
- Yves Jammes
- C2VN Inserm Inra, Faculty of Medicine, Aix Marseille University, Marseille, France, France
| | - Frédérique Retornaz
- Department of Internal Medicine, European Hospital, Marseille, France, France
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20
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Myalgic encephalomyelitis/chronic fatigue syndrome: From pathophysiological insights to novel therapeutic opportunities. Pharmacol Res 2019; 148:104450. [PMID: 31509764 DOI: 10.1016/j.phrs.2019.104450] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 08/26/2019] [Accepted: 09/06/2019] [Indexed: 12/12/2022]
Abstract
Myalgic encephalomyelitis (ME) or chronic fatigue syndrome (CFS) is a common and disabling condition with a paucity of effective and evidence-based therapies, reflecting a major unmet need. Cognitive behavioural therapy and graded exercise are of modest benefit for only some ME/CFS patients, and many sufferers report aggravation of symptoms of fatigue with exercise. The presence of a multiplicity of pathophysiological abnormalities in at least the subgroup of people with ME/CFS diagnosed with the current international consensus "Fukuda" criteria, points to numerous potential therapeutic targets. Such abnormalities include extensive data showing that at least a subgroup has a pro-inflammatory state, increased oxidative and nitrosative stress, disruption of gut mucosal barriers and mitochondrial dysfunction together with dysregulated bioenergetics. In this paper, these pathways are summarised, and data regarding promising therapeutic options that target these pathways are highlighted; they include coenzyme Q10, melatonin, curcumin, molecular hydrogen and N-acetylcysteine. These data are promising yet preliminary, suggesting hopeful avenues to address this major unmet burden of illness.
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21
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Missailidis D, Annesley SJ, Fisher PR. Pathological Mechanisms Underlying Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Diagnostics (Basel) 2019; 9:E80. [PMID: 31330791 PMCID: PMC6787592 DOI: 10.3390/diagnostics9030080] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/15/2019] [Accepted: 07/19/2019] [Indexed: 02/06/2023] Open
Abstract
The underlying molecular basis of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is not well understood. Characterized by chronic, unexplained fatigue, a disabling payback following exertion ("post-exertional malaise"), and variably presenting multi-system symptoms, ME/CFS is a complex disease, which demands a concerted biomedical investigation from disparate fields of expertise. ME/CFS research and patient treatment have been challenged by the lack of diagnostic biomarkers and finding these is a prominent direction of current work. Despite these challenges, modern research demonstrates a tangible biomedical basis for the disorder across many body systems. This evidence is mostly comprised of disturbances to immunological and inflammatory pathways, autonomic and neurological dysfunction, abnormalities in muscle and mitochondrial function, shifts in metabolism, and gut physiology or gut microbiota disturbances. It is possible that these threads are together entangled as parts of an underlying molecular pathology reflecting a far-reaching homeostatic shift. Due to the variability of non-overlapping symptom presentation or precipitating events, such as infection or other bodily stresses, the initiation of body-wide pathological cascades with similar outcomes stemming from different causes may be implicated in the condition. Patient stratification to account for this heterogeneity is therefore one important consideration during exploration of potential diagnostic developments.
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Affiliation(s)
- Daniel Missailidis
- Department of Physiology Anatomy and Microbiology, La Trobe University, VIC 3086, Australia
| | - Sarah J Annesley
- Department of Physiology Anatomy and Microbiology, La Trobe University, VIC 3086, Australia
| | - Paul R Fisher
- Department of Physiology Anatomy and Microbiology, La Trobe University, VIC 3086, Australia.
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22
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Morris G, Maes M, Berk M, Puri BK. Myalgic encephalomyelitis or chronic fatigue syndrome: how could the illness develop? Metab Brain Dis 2019; 34:385-415. [PMID: 30758706 PMCID: PMC6428797 DOI: 10.1007/s11011-019-0388-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 01/23/2019] [Indexed: 12/19/2022]
Abstract
A model of the development and progression of chronic fatigue syndrome (myalgic encephalomyelitis), the aetiology of which is currently unknown, is put forward, starting with a consideration of the post-infection role of damage-associated molecular patterns and the development of chronic inflammatory, oxidative and nitrosative stress in genetically predisposed individuals. The consequences are detailed, including the role of increased intestinal permeability and the translocation of commensal antigens into the circulation, and the development of dysautonomia, neuroinflammation, and neurocognitive and neuroimaging abnormalities. Increasing levels of such stress and the switch to immune and metabolic downregulation are detailed next in relation to the advent of hypernitrosylation, impaired mitochondrial performance, immune suppression, cellular hibernation, endotoxin tolerance and sirtuin 1 activation. The role of chronic stress and the development of endotoxin tolerance via indoleamine 2,3-dioxygenase upregulation and the characteristics of neutrophils, monocytes, macrophages and T cells, including regulatory T cells, in endotoxin tolerance are detailed next. Finally, it is shown how the immune and metabolic abnormalities of chronic fatigue syndrome can be explained by endotoxin tolerance, thus completing the model.
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Affiliation(s)
- Gerwyn Morris
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, Geelong, Victoria, Australia
| | - Michael Maes
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, Geelong, Victoria, Australia
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, Geelong, Victoria, Australia
- Department of Psychiatry, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- Florey Institute for Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
- Orygen, The National Centre of Excellence in Youth Mental Health, Parkville, Victoria, Australia
| | - Basant K Puri
- Department of Medicine, Imperial College London, Hammersmith Hospital, London, England, W12 0HS, UK.
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23
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Polli A, Van Oosterwijck J, Nijs J, Marusic U, De Wandele I, Paul L, Meeus M, Moorkens G, Lambrecht L, Ickmans K. Relationship Between Exercise-induced Oxidative Stress Changes and Parasympathetic Activity in Chronic Fatigue Syndrome: An Observational Study in Patients and Healthy Subjects. Clin Ther 2019; 41:641-655. [PMID: 30665828 DOI: 10.1016/j.clinthera.2018.12.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/10/2018] [Accepted: 12/14/2018] [Indexed: 02/07/2023]
Abstract
PURPOSE Oxidative stress has been proposed as a contributor to pain in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). During incremental exercise in patients with ME/CFS, oxidative stress enhances sooner and antioxidant response is delayed. We explored whether oxidative stress is associated with pain symptoms or pain changes following exercise, and the possible relationships between oxidative stress and parasympathetic vagal nerve activity in patients with ME/CFS versus healthy, inactive controls. METHODS The present study reports secondary outcomes from a previous work. Data from 36 participants were studied (women with ME/CFS and healthy controls). Subjects performed a submaximal exercise test with continuous cardiorespiratory monitoring. Levels of thiobarbituric acid-reactive substances (TBARSs) were used as a measure of oxidative stress, and heart rate variability was used to assess vagal activity. Before and after the exercise, subjects were asked to rate their pain using a visual analogic scale. FINDINGS Significant between-group differences in pain at both baseline and following exercise were found (both, P < 0.007). In healthy controls, pain was significantly improved following exercise (P = 0.002). No change in oxidative stress level after exercise was found. Significant correlation between TBARS levels and pain was found at baseline (r = 0.540; P = 0.021) and after exercise (r = 0.524; P = 0.024) in patients only. No significant correlation between TBARS and heart rate variability at baseline or following exercise was found in either group. However, a significant correlation was found between exercise-induced changes in HRV and TBARS in healthy controls (r = -0.720; P = 0.001). IMPLICATIONS Oxidative stress showed an association with pain symptoms in people with ME/CFS, but no exercise-induced changes in oxidative stress were found. In addition, the change in parasympathetic activity following exercise partially accounted for the change in oxidative stress in healthy controls. More research is required to further explore this link.
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Affiliation(s)
- Andrea Polli
- Pain in Motion International Research Group, Belgium(12); Department of Physiotherapy, Human Physiology and Anatomy, Faculty of Physical Education & Physiotherapy, Vrije Universiteit Brussel, Brussels, Belgium; Research Foundation-Flanders (FWO), Brussels, Belgium.
| | - Jessica Van Oosterwijck
- Pain in Motion International Research Group, Belgium(12); Research Foundation-Flanders (FWO), Brussels, Belgium; Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium; Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Jo Nijs
- Pain in Motion International Research Group, Belgium(12); Department of Physiotherapy, Human Physiology and Anatomy, Faculty of Physical Education & Physiotherapy, Vrije Universiteit Brussel, Brussels, Belgium; Department of Physical Medicine and Physiotherapy, University Hospital Brussels, Brussels, Belgium
| | - Uros Marusic
- Institute for Kinesiology Research, Science and Research Centre Koper, Koper, Slovenia; Department of Health Sciences, Alma Mater Europaea-ECM, Maribor, Slovenia
| | - Inge De Wandele
- Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Lorna Paul
- School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, United Kingdom
| | - Mira Meeus
- Pain in Motion International Research Group, Belgium(12); Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium; Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Greta Moorkens
- Department of Internal Medicine, University Hospital Antwerp (UZA), Antwerp, Belgium
| | - Luc Lambrecht
- Private Practice for Internal Medicine, Ghent, Belgium
| | - Kelly Ickmans
- Pain in Motion International Research Group, Belgium(12); Department of Physiotherapy, Human Physiology and Anatomy, Faculty of Physical Education & Physiotherapy, Vrije Universiteit Brussel, Brussels, Belgium; Department of Physical Medicine and Physiotherapy, University Hospital Brussels, Brussels, Belgium
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Germain A, Ruppert D, Levine SM, Hanson MR. Prospective Biomarkers from Plasma Metabolomics of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Implicate Redox Imbalance in Disease Symptomatology. Metabolites 2018; 8:metabo8040090. [PMID: 30563204 PMCID: PMC6315598 DOI: 10.3390/metabo8040090] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/30/2018] [Accepted: 12/04/2018] [Indexed: 12/20/2022] Open
Abstract
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a disease of enigmatic origin with no established cure. Its constellation of symptoms has silently ruined the lives of millions of people around the world. A plethora of hypotheses have been vainly investigated over the past few decades, so that the biological basis of this debilitating condition remains a mystery. In this study, we investigate whether there is a disturbance in homeostasis of metabolic networks in the plasma of a female 32-patient cohort compared to 19 healthy female controls. Extensive analysis of the 832-metabolite dataset generated by Metabolon®, covering eight biological classes, generated important insight into metabolic disruptions that occur in ME/CFS. We report on 14 metabolites with differences in abundance, allowing us to develop a theory of broad redox imbalance in ME/CFS patients, which is consistent with findings of prior work in the ME/CFS field. Moreover, exploration of enrichment analysis using www.MetaboAnalyst.ca provides information concerning similarities between metabolite disruptions in ME/CFS and those that occur in other diseases, while its biomarker analysis unit yielded prospective plasma biomarkers for ME/CFS. This work contributes key elements to the development of ME/CFS diagnostics, a crucial step required for discovering a therapy for any disease of unknown origin.
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Affiliation(s)
- Arnaud Germain
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
| | - David Ruppert
- Department of Statistical Science and School of Operations Research and Information Engineering, Cornell University, Ithaca, NY 14853, USA.
| | - Susan M Levine
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
| | - Maureen R Hanson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
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Monitoring Exercise-Induced Muscle Fatigue and Adaptations: Making Sense of Popular or Emerging Indices and Biomarkers. Sports (Basel) 2018; 6:sports6040153. [PMID: 30486243 PMCID: PMC6315493 DOI: 10.3390/sports6040153] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/17/2018] [Accepted: 11/21/2018] [Indexed: 11/17/2022] Open
Abstract
Regular exercise with the appropriate intensity and duration may improve an athlete’s physical capacities by targeting different performance determinants across the endurance–strength spectrum aiming to delay fatigue. The mechanisms of muscle fatigue depend on exercise intensity and duration and may range from substrate depletion to acidosis and product inhibition of adenosinetriphosphatase (ATPase) and glycolysis. Fatigue mechanisms have been studied in isolated muscles; single muscle fibers (intact or skinned) or at the level of filamentous or isolated motor proteins; with each approach contributing to our understanding of the fatigue phenomenon. In vivo methods for monitoring fatigue include the assessment of various functional indices supported by the use of biochemical markers including blood lactate levels and more recently redox markers. Blood lactate measurements; as an accompaniment of functional assessment; are extensively used for estimating the contribution of the anaerobic metabolism to energy expenditure and to help interpret an athlete’s resistance to fatigue during high intensity exercise. Monitoring of redox indices is gaining popularity in the applied sports performance setting; as oxidative stress is not only a fatigue agent which may play a role in the pathophysiology of overtraining syndrome; but also constitutes an important signaling pathway for training adaptations; thus reflecting training status. Careful planning of sampling and interpretation of blood biomarkers should be applied; especially given that their levels can fluctuate according to an athlete’s lifestyle and training histories.
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Blomberg J, Gottfries CG, Elfaitouri A, Rizwan M, Rosén A. Infection Elicited Autoimmunity and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: An Explanatory Model. Front Immunol 2018; 9:229. [PMID: 29497420 PMCID: PMC5818468 DOI: 10.3389/fimmu.2018.00229] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 01/26/2018] [Indexed: 12/13/2022] Open
Abstract
Myalgic encephalomyelitis (ME) often also called chronic fatigue syndrome (ME/CFS) is a common, debilitating, disease of unknown origin. Although a subject of controversy and a considerable scientific literature, we think that a solid understanding of ME/CFS pathogenesis is emerging. In this study, we compiled recent findings and placed them in the context of the clinical picture and natural history of the disease. A pattern emerged, giving rise to an explanatory model. ME/CFS often starts after or during an infection. A logical explanation is that the infection initiates an autoreactive process, which affects several functions, including brain and energy metabolism. According to our model for ME/CFS pathogenesis, patients with a genetic predisposition and dysbiosis experience a gradual development of B cell clones prone to autoreactivity. Under normal circumstances these B cell offsprings would have led to tolerance. Subsequent exogenous microbial exposition (triggering) can lead to comorbidities such as fibromyalgia, thyroid disorder, and orthostatic hypotension. A decisive infectious trigger may then lead to immunization against autoantigens involved in aerobic energy production and/or hormone receptors and ion channel proteins, producing postexertional malaise and ME/CFS, affecting both muscle and brain. In principle, cloning and sequencing of immunoglobulin variable domains could reveal the evolution of pathogenic clones. Although evidence consistent with the model accumulated in recent years, there are several missing links in it. Hopefully, the hypothesis generates testable propositions that can augment the understanding of the pathogenesis of ME/CFS.
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Affiliation(s)
- Jonas Blomberg
- Department of Medical Sciences, Uppsala University, Clinical Microbiology, Academic Hospital, Uppsala, Sweden
| | | | - Amal Elfaitouri
- Department of Infectious Disease and Tropical Medicine, Faculty of Public Health, Benghazi University, Benghazi, Libya
| | - Muhammad Rizwan
- Department of Medical Sciences, Uppsala University, Clinical Microbiology, Academic Hospital, Uppsala, Sweden
| | - Anders Rosén
- Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, Linköping, Sweden
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Alterations in Redox Homeostasis During Recovery From Unexplained Underperformance Syndrome in an Elite International Rower. Int J Sports Physiol Perform 2018; 13:107-111. [PMID: 28422588 DOI: 10.1123/ijspp.2016-0777] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE To examine a diagnosis of unexplained underperformance syndrome (UUPS, or overtraining syndrome) in an international rower describing a full recovery and return to elite competition the same year. METHODS On diagnosis and 4 and 14 mo postdiagnosis, detailed assessments including physiological, nutritional, and biomarkers were made. RESULTS Clinical examination and laboratory results for hematology, biochemistry, thyroid function, immunology, vitamins, and minerals were unremarkable and did not explain the presentation and diagnosis. Redox biomarkers including hydroperoxides, plasma antioxidant capacity, red blood cell glutathione, superoxide dismutase, coenzyme Q10, vitamin E (α- and γ-tocopherol), and carotenoids (lutein, α-carotene, β-carotene) provided evidence of altered redox homeostasis. The recovery strategy began with 12 d of training abstinence and nutritional interventions, followed by 6 wk of modified training. At 4 mo postintervention, performance had recovered strongly, resulting in the athlete's becoming European champion that same year. Further improvements in physiological and performance indices were observed at 14 mo postintervention. Physiologically relevant increases in concentrations of carotenoids were achieved at each postintervention time point, exceeding the reported critical-difference values. CONCLUSIONS Increasing athlete phytonutrient intake may enhance recovery and tolerance of training and environmental stressors, reducing the risk of unexplained UUPS. Alterations in redox homeostasis should be considered as part of the medical management in UUPS. This is the first reported case study of an elite athlete with alterations in redox homeostasis in conjunction with a diagnosis of UUPS.
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Mechanisms Explaining Muscle Fatigue and Muscle Pain in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a Review of Recent Findings. Curr Rheumatol Rep 2017; 19:1. [PMID: 28116577 DOI: 10.1007/s11926-017-0628-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW Here, we review potential causes of muscle dysfunction seen in many patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) such as the effects of oxidative and nitrosative stress (O&NS) and mitochondrial impairments together with reduced heat shock protein production and a range of metabolic abnormalities. RECENT FINDINGS Several studies published in the last few years have highlighted the existence of chronic O&NS, inflammation, impaired mitochondrial function and reduced heat shock protein production in many patients with ME/CFS. These studies have also highlighted the detrimental effects of chronically elevated O&NS on muscle functions such as reducing the time to muscle fatigue during exercise and impairing muscle contractility. Mechanisms have also been revealed by which chronic O&NS and or impaired heat shock production may impair muscle repair following exercise and indeed the adaptive responses in the striated muscle to acute and chronic increases in physical activity. The presence of chronic O&NS, low-grade inflammation and impaired heat shock protein production may well explain the objective findings of increased muscle fatigue, impaired contractility and multiple dimensions of exercise intolerance in many patients with ME/CFS.
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Scheibenbogen C, Freitag H, Blanco J, Capelli E, Lacerda E, Authier J, Meeus M, Castro Marrero J, Nora-Krukle Z, Oltra E, Strand EB, Shikova E, Sekulic S, Murovska M. The European ME/CFS Biomarker Landscape project: an initiative of the European network EUROMENE. J Transl Med 2017; 15:162. [PMID: 28747192 PMCID: PMC5530475 DOI: 10.1186/s12967-017-1263-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 07/14/2017] [Indexed: 12/18/2022] Open
Abstract
Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) is a common and severe disease with a considerable social and economic impact. So far, the etiology is not known, and neither a diagnostic marker nor licensed treatments are available yet. The EUROMENE network of European researchers and clinicians aims to promote cooperation and advance research on ME/CFS. To improve diagnosis and facilitate the analysis of clinical trials surrogate markers are urgently needed. As a first step for developing such biomarkers for clinical use a database of active biomarker research in Europe was established called the ME/CFS EUROMENE Biomarker Landscape project and the results are presented in this review. Further we suggest strategies to improve biomarker development and encourage researchers to take these into consideration for designing and reporting biomarker studies.
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Affiliation(s)
- Carmen Scheibenbogen
- Institute for Medical Immunology, Charité-Universitätsmedizin Berlin, Campus Virchow, Augustenburger Platz 1/Sudstrasse 2, 13353 Berlin, Germany
| | - Helma Freitag
- Institute for Medical Immunology, Charité-Universitätsmedizin Berlin, Campus Virchow, Augustenburger Platz 1/Sudstrasse 2, 13353 Berlin, Germany
| | - Julià Blanco
- Institut de Recerca de la Sida IrsiCaixa-HIVACAT, Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol, IGTP, UAB, Carretera del Canyet, s/n, 08916 Badalona, Spain
- Universitat de Vic-UCC, Carrer de la Sagrada Família, 7, 08500 Vic Barcelona, Spain
| | - Enrica Capelli
- Deptartment of Earth and Environmental Sciences, University of Pavia, Via Ferrata 7, 27100 Pavia, Italy
- Centre for Health Technologies (CHT), University of Pavia, Via Ferrata 5, 27100 Pavia, Italy
| | - Eliana Lacerda
- Clinical Research Department, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel St, Bloomsbury, London, WC1E 7HT UK
| | - Jerome Authier
- Faculty of Medicine, Paris Est-Creteil University, 8 rue du General Sarrail, 94000 Creteil, France
| | - Mira Meeus
- Pain in Motion International Research Group, Brussels, Belgium
- Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University, St. Pietersnieuwstraat 33, 9000 Ghent, Belgium
- Department of Rehabilitation Sciences and Physiotherapy (MOVANT), Faculty of Medicine and Health Sciences, University of Antwerp, Prinsstraat 13, 2000 Antwerp, Belgium
| | - Jesus Castro Marrero
- Vall d’Hebron University Hospital, CFS/ME Unit, Universitat Autònoma de Barcelona, 119-129, Passeig de la Vall d’Hebron, 08035 Barcelona, Spain
| | - Zaiga Nora-Krukle
- August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Dzirciema iela 16, Kurzemes rajons, Rīga, 1007 Latvia
| | - Elisa Oltra
- Facultad de Medicina, Universidad Católica de Valencia, San Vicente Mártir, Carrer de Quevedo, 2, 46001 Valencia, Spain
- Instituto Valenciano de Patología (IVP) de la Universidad Católica de Valencia San Vicente Mártir, Centro de Investigación Príncipe Felipe (CIPF), Carrer d’Eduardo Primo Yúfera, 3, 46012 Valencia, Spain
| | - Elin Bolle Strand
- Division of Medicine, CFS/ME Center, Oslo University Hospital, Aker, Trondheimsveien 235, 0586 Oslo, Norway
- Department of Paediatrics, Norwegian National Advisory Unit on CFS/ME, Rikshospitalet, Sognsvannsveien 20, 0372 Oslo, Norway
| | - Evelina Shikova
- Department of Virology, National Center of Infectious and Parasitic Diseases, 44A General Stoletov blvd., 1233 Sofia, Bulgaria
| | - Slobodan Sekulic
- Department of Neurology, Medical Faculty Novi Sad, Hajduk Veljkova 3, 21000 Novi Sad, Serbia
| | - Modra Murovska
- August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Dzirciema iela 16, Kurzemes rajons, Rīga, 1007 Latvia
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Joustra ML, Minovic I, Janssens KAM, Bakker SJL, Rosmalen JGM. Vitamin and mineral status in chronic fatigue syndrome and fibromyalgia syndrome: A systematic review and meta-analysis. PLoS One 2017; 12:e0176631. [PMID: 28453534 PMCID: PMC5409455 DOI: 10.1371/journal.pone.0176631] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 04/13/2017] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Many chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS) patients (35-68%) use nutritional supplements, while it is unclear whether deficiencies in vitamins and minerals contribute to symptoms in these patients. Objectives were (1) to determine vitamin and mineral status in CFS and FMS patients as compared to healthy controls; (2) to investigate the association between vitamin and mineral status and clinical parameters, including symptom severity and quality of life; and (3) to determine the effect of supplementation on clinical parameters. METHODS The databases PubMed, EMBASE, Web of Knowledge, and PsycINFO were searched for eligible studies. Articles published from January 1st 1994 for CFS patients and 1990 for FMS patients till March 1st 2017 were included. Articles were included if the status of one or more vitamins or minerals were reported, or an intervention concerning vitamins or minerals was performed. Two reviewers independently extracted data and assessed the risk of bias. RESULTS A total of 5 RCTs and 40 observational studies were included in the qualitative synthesis, of which 27 studies were included in the meta-analyses. Circulating concentrations of vitamin E were lower in patients compared to controls (pooled standardized mean difference (SMD): -1.57, 95%CI: -3.09, -0.05; p = .042). However, this difference was not present when restricting the analyses to the subgroup of studies with high quality scores. Poor study quality and a substantial heterogeneity in most studies was found. No vitamins or minerals have been repeatedly or consistently linked to clinical parameters. In addition, RCTs testing supplements containing these vitamins and/or minerals did not result in clinical improvements. DISCUSSION Little evidence was found to support the hypothesis that vitamin and mineral deficiencies play a role in the pathophysiology of CFS and FMS, and that the use of supplements is effective in these patients. REGISTRATION Study methods were documented in an international prospective register of systematic reviews (PROSPERO) protocol, registration number: http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42015032528.
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Affiliation(s)
- Monica L. Joustra
- Interdisciplinary Center Psychopathology and Emotion regulation, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Isidor Minovic
- Department of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- Top Institute Food and Nutrition, Wageningen, the Netherlands
| | - Karin A. M. Janssens
- Interdisciplinary Center Psychopathology and Emotion regulation, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Stephan J. L. Bakker
- Department of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- Top Institute Food and Nutrition, Wageningen, the Netherlands
| | - Judith G. M. Rosmalen
- Interdisciplinary Center Psychopathology and Emotion regulation, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
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Nam SY, Kim HM, Jeong HJ. Anti-fatigue effect by active dipeptides of fermented porcine placenta through inhibiting the inflammatory and oxidative reactions. Biomed Pharmacother 2016; 84:51-59. [PMID: 27636512 DOI: 10.1016/j.biopha.2016.09.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 08/26/2016] [Accepted: 09/06/2016] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Recently, we reported an anti-fatigue effect of fermented porcine placenta (FPP). Glycine-leucine (GL) and leucine-glycine (LG) dipeptides are main peptides of FPP. However, the therapeutic effects and underlying mechanisms of GL and LG dipeptides on fatigue are still unclear. METHODS Herein, we examined the anti-fatigue properties of GL and LG dipeptides using RAW264.7 macrophages and forced swimming test (FST) animal model. RESULTS Our data revealed that lipopolysaccharide (LPS)-induced interleukin (IL)-1β, tumor necrosis factor-α, and IL-6 productions were markedly inhibited by GL or LG in RAW264.7 macrophages without inducing cytotoxicity. LPS-enhanced nitric oxide (NO) production and inducible nitric oxide synthase expression were inhibited by GL or LG, whereas superoxide dismutase (SOD) activities were significantly enhanced by GL or LG in LPS-stimulated RAW264.7 macrophages. The present study also figured out that these effects of GL and LG were mediated by blockade of caspase-1 and nuclear factor-κB activation. In FST-induced fatigue mouse model, the mice which received the GL or LG for 21days showed significant decreases of IL-1β, IL-6, and NO serum levels. Treatment with GL or LG significantly enhanced levels of SOD and glycogen and significantly lowered levels of lactate dehydrogenase, aspartate transaminase, and alanine transaminase. CONCLUSION Taken together, our results indicated that GL and LG dipeptides, active components of FPP, should be considered as candidate of anti-fatigue agents.
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Affiliation(s)
- Sun-Young Nam
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Hyung-Min Kim
- Department of Pharmacology, College of Korean Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea.
| | - Hyun-Ja Jeong
- Department of Food Technology and Inflammatory Disease Research Center, Hoseo University, Asan, Chungnam, 31499, Republic of Korea.
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Fenouillet E, Vigouroux A, Steinberg JG, Chagvardieff A, Retornaz F, Guieu R, Jammes Y. Association of biomarkers with health-related quality of life and history of stressors in myalgic encephalomyelitis/chronic fatigue syndrome patients. J Transl Med 2016; 14:251. [PMID: 27580693 PMCID: PMC5006431 DOI: 10.1186/s12967-016-1010-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 08/16/2016] [Indexed: 12/15/2022] Open
Abstract
Background Myalgic encephalomyelitis chronic fatigue syndrome (ME/CFS) is a common debilitating disorder associated with an intense fatigue, a reduced physical activity, and an impaired quality of life. There are no established biological markerof the syndrome. The etiology is unknown and its pathogenesis appears to be multifactorial. Various stressors, including intense physical activity, severe infection, and emotional stress are reported in the medical history of ME/CFS patients which raises the question whether any physiological and biological abnormalities usually found in these patients could be indicative of the etiology and/or the quality-of-life impairment. Methods Thirty-six patients and 11 age-matched healthy controls were recruited. The following variables that appear to address common symptoms of ME/CFS were studied here: (1) muscle fatigue during exercise has been investigated by monitoring the compound muscle action potential (M-wave); (2) the excessive oxidative stress response to exercise was measured via two plasma markers (thiobarbituric acid reactive substances: TBARS; reduced ascorbic-acid: RAA); (3) a potential inflammatory component was addressed via expression of CD26 on peripheral blood mononuclear cells; (4) quality-of-life impairment was assessed using the London Handicap Scale (LHS) and the Medical Outcome Study Short Form-36 (SF-36). The medical history of each patient, including the presence of stressors such as intense sports practice, severe acute infection and/or severe emotional stress was documented. Results We observed that: (1) there were striking differences between cases and controls with regard to three biological variables: post-exercise M-wave, TBARS variations and CD26-expression at rest; (2) each of these three variables correlated with the other two; (3) abnormalities in the biomarkers associated with health-related quality of life: the LHS score was negatively correlated with the exercise-induced TBARS increase and positively correlated with CD26-expression while the pain component of SF-36 was negatively correlated with CD26-expression; (4) the TBARS increase and the M-wave decrease were the highest, and the CD26-expression level the lowest in patients who had been submitted to infectious stressors. Conclusion In ME/CFS patients, severe alterations of the muscle excitability, the redox status, as well as the CD26-expression level are correlated with a marked impairment of the quality-of-life. They are particularly significant when infectious stressors are reported in the medical history.
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Affiliation(s)
- Emmanuel Fenouillet
- DS-ACI UMR MD2, Faculty of Medicine, Aix-Marseille University, Bd. Pierre Dramard, 13916, Marseille Cedex 20, France.,CNRS, Institut des Sciences Biologiques, Marseille, France
| | - Aude Vigouroux
- Clinical Respiratory Physiology Laboratory, Nord Hospital, Marseille, France
| | - Jean Guillaume Steinberg
- DS-ACI UMR MD2, Faculty of Medicine, Aix-Marseille University, Bd. Pierre Dramard, 13916, Marseille Cedex 20, France
| | | | | | - Regis Guieu
- DS-ACI UMR MD2, Faculty of Medicine, Aix-Marseille University, Bd. Pierre Dramard, 13916, Marseille Cedex 20, France
| | - Yves Jammes
- DS-ACI UMR MD2, Faculty of Medicine, Aix-Marseille University, Bd. Pierre Dramard, 13916, Marseille Cedex 20, France. .,Clinical Respiratory Physiology Laboratory, Nord Hospital, Marseille, France.
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Understanding Muscle Dysfunction in Chronic Fatigue Syndrome. J Aging Res 2016; 2016:2497348. [PMID: 26998359 PMCID: PMC4779819 DOI: 10.1155/2016/2497348] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 12/12/2015] [Accepted: 01/13/2016] [Indexed: 12/11/2022] Open
Abstract
Introduction. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a debilitating disorder of unknown aetiology, characterised by severe disabling fatigue in the absence of alternative diagnosis. Historically, there has been a tendency to draw psychological explanations for the origin of fatigue; however, this model is at odds with findings that fatigue and accompanying symptoms may be explained by central and peripheral pathophysiological mechanisms, including effects of the immune, oxidative, mitochondrial, and neuronal pathways. For example, patient descriptions of their fatigue regularly cite difficulty in maintaining muscle activity due to perceived lack of energy. This narrative review examined the literature for evidence of biochemical dysfunction in CFS/ME at the skeletal muscle level. Methods. Literature was examined following searches of PUB MED, MEDLINE, and Google Scholar, using key words such as CFS/ME, immune, autoimmune, mitochondria, muscle, and acidosis. Results. Studies show evidence for skeletal muscle biochemical abnormality in CFS/ME patients, particularly in relation to bioenergetic dysfunction. Discussion. Bioenergetic muscle dysfunction is evident in CFS/ME, with a tendency towards an overutilisation of the lactate dehydrogenase pathway following low-level exercise, in addition to slowed acid clearance after exercise. Potentially, these abnormalities may lead to the perception of severe fatigue in CFS/ME.
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Faure A, Bruzzese L, Steinberg JG, Jammes Y, Torrents J, Berdah SV, Garnier E, Legris T, Loundou A, Chalopin M, Magalon G, Guieu R, Fenouillet E, Lechevallier E. Effectiveness of pure argon for renal transplant preservation in a preclinical pig model of heterotopic autotransplantation. J Transl Med 2016; 14:40. [PMID: 26847569 PMCID: PMC4743167 DOI: 10.1186/s12967-016-0795-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 01/20/2016] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND In kidney transplantation, the conditions of organ preservation following removal influence function recovery. Current static preservation procedures are generally based on immersion in a cold-storage solution used under atmospheric air (approximately 78 kPa N2, 21 kPa O2, 1 kPa Ar). Research on static cold-preservation solutions has stalled, and modifying the gas composition of the storage medium for improving preservation was considered. Organoprotective strategies successfully used noble gases and we addressed here the effects of argon and xenon on graft preservation in an established preclinical pig model of autotransplantation. METHODS The preservation solution Celsior saturated with pure argon (Argon-Celsior) or xenon (Xenon-Celsior) at atmospheric pressure was tested versus Celsior saturated with atmospheric air (Air-Celsior). The left kidney was removed, and Air-Celsior (n = 8 pigs), Argon-Celsior (n = 8) or Xenon-Celsior (n = 6) was used at 4 °C to flush and store the transplant for 30 h, a duration that induced ischemic injury in our model when Air-Celsior was used. Heterotopic autotransplantation and contralateral nephrectomy were performed. Animals were followed for 21 days. RESULTS The use of Argon-Celsior vs. Air-Celsior: (1) improved function recovery as monitored via creatinine clearance, the fraction of excreted sodium and tubulopathy duration; (2) enabled diuresis recovery 2-3 days earlier; (3) improved survival (7/8 vs. 3/8 pigs survived at postoperative day-21); (4) decreased tubular necrosis, interstitial fibrosis, apoptosis and inflammation, and preserved tissue structures as observed after the natural death/euthanasia; (5) stimulated plasma antioxidant defences during the days following transplantation as shown by monitoring the "reduced ascorbic acid/thiobarbituric acid reactive substances" ratio and Hsp27 expression; (6) limited the inflammatory response as shown by expression of TNF-alpha, IL1-beta and IL6 as observed after the natural death/euthanasia. Conversely, Xenon-Celsior was detrimental, no animal surviving by day-8 in a context where functional recovery, renal tissue properties and the antioxidant and inflammation responses were significantly altered. Thus, the positive effects of argon were not attributable to the noble gases as a group. CONCLUSIONS The saturation of Celsior with argon improved early functional recovery, graft quality and survival. Manipulating the gas composition of a preservation medium constitutes therefore a promising approach to improve preservation.
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Affiliation(s)
- Alice Faure
- Department of Urology and Kidney Transplantation, Aix-Marseille University, APHM, Marseille, France.
| | - Laurie Bruzzese
- UMR MD2 & IRBA, Aix-Marseille University, Marseille, France.
| | | | - Yves Jammes
- UMR MD2 & IRBA, Aix-Marseille University, Marseille, France.
| | - Julia Torrents
- Department of Pathology, Aix-Marseille University, APHM, Marseille, France.
| | - Stephane V Berdah
- C.E.R.C, Aix-Marseille University, Faculty of Medicine, Marseille, France.
| | - Emmanuelle Garnier
- C.E.R.C, Aix-Marseille University, Faculty of Medicine, Marseille, France.
| | - Tristan Legris
- Department of Nephrology and Kidney Transplantation, Aix-Marseille University, APHM, Marseille, France.
| | - Anderson Loundou
- Public Health Laboratory, Aix-Marseille University, Marseille, France.
| | - Matthieu Chalopin
- Air Liquide Medical Gases Group, Air Liquide sante International-Claude Delorme Research Center, Jouy-en-Josas, France.
| | - Guy Magalon
- Department of Plastic Surgery, Aix-Marseille University, APHM, Marseille, France.
| | - Regis Guieu
- UMR MD2 & IRBA, Aix-Marseille University, Marseille, France.
| | - Emmanuel Fenouillet
- UMR MD2 & IRBA, Aix-Marseille University, Marseille, France. .,Institut des Sciences Biologiques, CNRS, Paris, France.
| | - Eric Lechevallier
- Department of Urology and Kidney Transplantation, Aix-Marseille University, APHM, Marseille, France.
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Lewis NA, Collins D, Pedlar CR, Rogers JP. Can clinicians and scientists explain and prevent unexplained underperformance syndrome in elite athletes: an interdisciplinary perspective and 2016 update. BMJ Open Sport Exerc Med 2015; 1:e000063. [PMID: 27900140 PMCID: PMC5117038 DOI: 10.1136/bmjsem-2015-000063] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2015] [Indexed: 12/15/2022] Open
Abstract
The coach and interdisciplinary sports science and medicine team strive to continually progress the athlete's performance year on year. In structuring training programmes, coaches and scientists plan distinct periods of progressive overload coupled with recovery for anticipated performances to be delivered on fixed dates of competition in the calendar year. Peaking at major championships is a challenge, and training capacity highly individualised, with fine margins between the training dose necessary for adaptation and that which elicits maladaptation at the elite level. As such, optimising adaptation is key to effective preparation. Notably, however, many factors (eg, health, nutrition, sleep, training experience, psychosocial factors) play an essential part in moderating the processes of adaptation to exercise and environmental stressors, for example, heat, altitude; processes which can often fail or be limited. In the UK, the term unexplained underperformance syndrome (UUPS) has been adopted, in contrast to the more commonly referenced term overtraining syndrome, to describe a significant episode of underperformance with persistent fatigue, that is, maladaptation. This construct, UUPS, reflects the complexity of the syndrome, the multifactorial aetiology, and that ‘overtraining’ or an imbalance between training load and recovery may not be the primary cause for underperformance. UUPS draws on the distinction that a decline in performance represents the universal feature. In our review, we provide a practitioner-focused perspective, proposing that causative factors can be identified and UUPS explained, through an interdisciplinary approach (ie, medicine, nutrition, physiology, psychology) to sports science and medicine delivery, monitoring, and data interpretation and analysis.
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Affiliation(s)
- Nathan A Lewis
- ORRECO Ltd, Institute of Technology, Sligo, Ireland
- English Institute of Sport, Bath, UK
- School of Sport, Health and Applied Science, St Mary's University, Twickenham, London, UK
| | - Dave Collins
- Institute of Coaching and Performance (ICAP), University of Central Lancashire, Preston, UK
- Grey Matters Performance Ltd., Preston, UK
| | - Charles R Pedlar
- ORRECO Ltd, Institute of Technology, Sligo, Ireland
- School of Sport, Health and Applied Science, St Mary's University, Twickenham, London, UK
| | - John P Rogers
- ORRECO Ltd, Institute of Technology, Sligo, Ireland
- University Hospital of South Manchester NHS Foundation Trust, Manchester, UK
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Lewis NA, Howatson G, Morton K, Hill J, Pedlar CR. Alterations in redox homeostasis in the elite endurance athlete. Sports Med 2015; 45:379-409. [PMID: 25319354 DOI: 10.1007/s40279-014-0276-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The production of reactive oxygen (ROS) and nitrogen species (RNS) is a fundamental feature of mammalian physiology, cellular respiration and cell signalling, and essential for muscle function and training adaptation. Aerobic and anaerobic exercise results in alterations in redox homeostasis (ARH) in untrained, trained and well trained athletes. Low to moderate doses of ROS and RNS play a role in muscle adaptation to endurance training, but an overwhelming increase in RNS and ROS may lead to increased cell apoptosis and immunosuppression, fatigued states and underperformance. OBJECTIVES The objectives of this systematic review are: (a) to test the hypotheses that ARH occur in elite endurance athletes; following an acute exercise bout, in an endurance race or competition; across a micro-, meso- or macro-training cycle; following a training taper; before, during and after altitude training; in females with amenorrhoea versus eumenorrhoea; and in non-functional over-reaching (NFOR) and overtraining states (OTS); (b) to report any relationship between ARH and training load and ARH and performance; and (c) to apply critical difference values for measures of oxidative stress/ARH to address whether there is any evidence of ARH being of physiological significance (not just statistical) and thus relevant to health and performance in the elite athlete. METHODS Electronic databases, Embase, MEDLINE, and SPORTDiscus were searched for relevant articles. Only studies that were observational articles of cross-sectional or longitudinal design, and included elite athletes competing at national or international level in endurance sports were included. Studies had to include biomarkers of ARH; oxidative damage, antioxidant enzymes, antioxidant capacity, and antioxidant vitamins and nutrients in urine, serum, plasma, whole blood, red blood cells (RBCs) and white blood cells (WBCs). A total of 3,057 articles were identified from the electronic searches. Twenty-eight articles met the inclusion criteria and were included in the review. RESULTS ARH occurs in elite endurance athletes, after acute exercise, a competition or race, across training phases, and with natural or simulated altitude. A reduction in ARH occurs across the season in elite athletes, with marked variation around intensified training phases, between individuals, and the greatest disturbances (of physiological significance) occurring with live-high-train-low techniques, and in athletes competing. A relationship with ARH and performance and illness exists in elite athletes. There was considerable heterogeneity across the studies for the biomarkers and assays used; the sport; the blood sampling time points; and the phase in the annual training cycle and thus baseline athlete fitness. In addition, there was a consistent lack of reporting of the analytical variability of the assays used to assess ARH. CONCLUSIONS The reported biochemical changes around ARH in elite athletes suggest that it may be of value to monitor biomarkers of ARH at rest, pre- and post-simulated performance tests, and before and after training micro- and meso-cycles, and altitude camps, to identify individual tolerance to training loads, potentially allowing the prevention of non-functionally over-reached states and optimisation of the individual training taper and training programme.
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Morris G, Berk M, Galecki P, Walder K, Maes M. The Neuro-Immune Pathophysiology of Central and Peripheral Fatigue in Systemic Immune-Inflammatory and Neuro-Immune Diseases. Mol Neurobiol 2015; 53:1195-1219. [PMID: 25598355 DOI: 10.1007/s12035-015-9090-9] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 01/05/2015] [Indexed: 01/18/2023]
Abstract
Many patients with systemic immune-inflammatory and neuro-inflammatory disorders, including depression, rheumatoid arthritis, systemic lupus erythematosus, Sjögren's disease, cancer, cardiovascular disorder, Parkinson's disease, multiple sclerosis, stroke, and chronic fatigue syndrome/myalgic encephalomyelitis, endure pathological levels of fatigue. The aim of this narrative review is to delineate the wide array of pathways that may underpin the incapacitating fatigue occurring in systemic and neuro-inflammatory disorders. A wide array of immune, inflammatory, oxidative and nitrosative stress (O&NS), bioenergetic, and neurophysiological abnormalities are involved in the etiopathology of these disease states and may underpin the incapacitating fatigue that accompanies these disorders. This range of abnormalities comprises: increased levels of pro-inflammatory cytokines, e.g., interleukin-1 (IL-1), IL-6, tumor necrosis factor (TNF) α and interferon (IFN) α; O&NS-induced muscle fatigue; activation of the Toll-Like Receptor Cycle through pathogen-associated (PAMPs) and damage-associated (DAMPs) molecular patterns, including heat shock proteins; altered glutaminergic and dopaminergic neurotransmission; mitochondrial dysfunctions; and O&NS-induced defects in the sodium-potassium pump. Fatigue is also associated with altered activities in specific brain regions and muscle pathology, such as reductions in maximum voluntary muscle force, downregulation of the mitochondrial biogenesis master gene peroxisome proliferator-activated receptor gamma coactivator 1-alpha, a shift to glycolysis and buildup of toxic metabolites within myocytes. As such, both mental and physical fatigue, which frequently accompany immune-inflammatory and neuro-inflammatory disorders, are the consequence of interactions between multiple systemic and central pathways.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Bryn Road seaside 87, Llanelli, SA152LW, Wales, UK
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, P.O. Box 291, Geelong, 3220, Australia.,Orygen Youth Health Research Centre and the Centre of Youth Mental Health, Poplar Road 35, Parkville, 3052, Australia.,The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Kenneth Myer Building, Royal Parade 30, Parkville, 3052, Australia.,Department of Psychiatry, University of Melbourne, Level 1 North, Main Block, Royal Melbourne Hospital, Parkville, 3052, Australia
| | - Piotr Galecki
- Department of Adult Psychiatry, Medical University of Lodz, Lodz, Poland
| | - Ken Walder
- Metabolic Research Unit, Deakin University, Geelong, Australia
| | - Michael Maes
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, P.O. Box 291, Geelong, 3220, Australia. .,Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. .,Health Sciences Graduate Program, Health Sciences Center, State University of Londrina, Londrina, Brazil. .,Impact Strategic Research Center, Deakin University, Geelong, Australia.
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Loshaj-Shala A, Poceva Panovska A, Brezovska K, Beretta G, Suturkova L, Apostolski S. Involvement of serum HSP 70 in Guillain-Barré Syndrome: An exploratory study and a review of current literature. MAKEDONSKO FARMACEVTSKI BILTEN 2015. [DOI: 10.33320/maced.pharm.bull.2015.61.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The evolutionary conserved family of heat shock proteins (HSP) is responsible for protecting cells against different types of stress. Although the levels of HSP can be readily measured in serum, the levels of HSP 70 in patients Guillain-Barre Syndrome (GBS) have not been studied before. To this aim we investigate whether patients with GBS (n=21) had altered serum HSP 70 levels compared to healthy controls (HC, n=9) and to patients affected by other immune disorders such as multifocal motor neuropathy (MMN, n=4) and chronic inflammatory demyelinating polyneuropathy (CIDP, n=6). The highest HSP 70 value (15.78 ± 1.72 ng/mL) was found in one patient in the GBS group, although we have found that serum HSP70 levels were significantly higher in 2 out of the 21 GBS patients (9.5%). Hence, it is of interest to underline that the patient with the highest HSP70 level, had also the best recovery rate. Моrе extensive research is required in order to support the hypothesis that HSP 70 serum concentration may be a useful biomarker for the prediction of remission outcome for GBS patients.
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Pagano G, Aiello Talamanca A, Castello G, Cordero MD, d'Ischia M, Gadaleta MN, Pallardó FV, Petrović S, Tiano L, Zatterale A. Oxidative stress and mitochondrial dysfunction across broad-ranging pathologies: toward mitochondria-targeted clinical strategies. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:541230. [PMID: 24876913 PMCID: PMC4024404 DOI: 10.1155/2014/541230] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 02/24/2014] [Indexed: 02/07/2023]
Abstract
Beyond the disorders recognized as mitochondrial diseases, abnormalities in function and/or ultrastructure of mitochondria have been reported in several unrelated pathologies. These encompass ageing, malformations, and a number of genetic or acquired diseases, as diabetes and cardiologic, haematologic, organ-specific (e.g., eye or liver), neurologic and psychiatric, autoimmune, and dermatologic disorders. The mechanistic grounds for mitochondrial dysfunction (MDF) along with the occurrence of oxidative stress (OS) have been investigated within the pathogenesis of individual disorders or in groups of interrelated disorders. We attempt to review broad-ranging pathologies that involve mitochondrial-specific deficiencies or rely on cytosol-derived prooxidant states or on autoimmune-induced mitochondrial damage. The established knowledge in these subjects warrants studies aimed at elucidating several open questions that are highlighted in the present review. The relevance of OS and MDF in different pathologies may establish the grounds for chemoprevention trials aimed at compensating OS/MDF by means of antioxidants and mitochondrial nutrients.
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Affiliation(s)
- Giovanni Pagano
- Cancer Research Centre at Mercogliano (CROM), Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy
| | - Annarita Aiello Talamanca
- Cancer Research Centre at Mercogliano (CROM), Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy
| | - Giuseppe Castello
- Cancer Research Centre at Mercogliano (CROM), Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, 80131 Naples, Italy
| | - Mario D. Cordero
- Research Laboratory, Dental School, Sevilla University, 41009 Sevilla, Spain
| | - Marco d'Ischia
- Department of Chemical Sciences, Federico II University, 80126 Naples, Italy
| | - Maria Nicola Gadaleta
- National Research Council, Institute of Biomembranes and Bioenergetics, 70126 Bari, Italy
| | | | - Sandra Petrović
- “Vinca” Institute of Nuclear Sciences, University of Belgrade, 11070 Belgrade, Serbia
| | - Luca Tiano
- Department of Clinical and Dental Sciences, Polytechnical University of Marche, 60100 Ancona, Italy
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Twisk FNM. The status of and future research into Myalgic Encephalomyelitis and Chronic Fatigue Syndrome: the need of accurate diagnosis, objective assessment, and acknowledging biological and clinical subgroups. Front Physiol 2014; 5:109. [PMID: 24734022 PMCID: PMC3974331 DOI: 10.3389/fphys.2014.00109] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 03/04/2014] [Indexed: 12/26/2022] Open
Abstract
Although Myalgic Encephalomyelitis (ME) and Chronic Fatigue Syndrome (CFS) are used interchangeably, the diagnostic criteria define two distinct clinical entities. Cognitive impairment, (muscle) weakness, circulatory disturbances, marked variability of symptoms, and, above all, post-exertional malaise: a long-lasting increase of symptoms after a minor exertion, are distinctive symptoms of ME. This latter phenomenon separates ME, a neuro-immune illness, from chronic fatigue (syndrome), other disorders and deconditioning. The introduction of the label, but more importantly the diagnostic criteria for CFS have generated much confusion, mostly because chronic fatigue is a subjective and ambiguous notion. CFS was redefined in 1994 into unexplained (persistent or relapsing) chronic fatigue, accompanied by at least four out of eight symptoms, e.g., headaches and unrefreshing sleep. Most of the research into ME and/or CFS in the last decades was based upon the multivalent CFS criteria, which define a heterogeneous patient group. Due to the fact that fatigue and other symptoms are non-discriminative, subjective experiences, research has been hampered. Various authors have questioned the physiological nature of the symptoms and qualified ME/CFS as somatization. However, various typical symptoms can be assessed objectively using standardized methods. Despite subjective and unclear criteria and measures, research has observed specific abnormalities in ME/CFS repetitively, e.g., immunological abnormalities, oxidative and nitrosative stress, neurological anomalies, circulatory deficits and mitochondrial dysfunction. However, to improve future research standards and patient care, it is crucial that patients with post-exertional malaise (ME) and patients without this odd phenomenon are acknowledged as separate clinical entities that the diagnosis of ME and CFS in research and clinical practice is based upon accurate criteria and an objective assessment of characteristic symptoms, as much as possible that well-defined clinical and biological subgroups of ME and CFS patients are investigated in more detail, and that patients are monitored before, during and after interventions with objective measures and biomarkers.
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Morris G, Maes M. Oxidative and Nitrosative Stress and Immune-Inflammatory Pathways in Patients with Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS). Curr Neuropharmacol 2014; 12:168-85. [PMID: 24669210 PMCID: PMC3964747 DOI: 10.2174/1570159x11666131120224653] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 07/12/2013] [Accepted: 11/02/2013] [Indexed: 02/07/2023] Open
Abstract
Myalgic Encephalomyelitis (ME) / Chronic Fatigue Syndrome (CFS) has been classified as a disease of the central nervous system by the WHO since 1969. Many patients carrying this diagnosis do demonstrate an almost bewildering array of biological abnormalities particularly the presence of oxidative and nitrosative stress (O&NS) and a chronically activated innate immune system. The proposal made herein is that once generated chronically activated O&NS and immune-inflammatory pathways conspire to generate a multitude of self-sustaining and self-amplifying pathological processes which are associated with the onset of ME/CFS. Sources of continuous activation of O&NS and immune-inflammatory pathways in ME/CFS are chronic, intermittent and opportunistic infections, bacterial translocation, autoimmune responses, mitochondrial dysfunctions, activation of the Toll-Like Receptor Radical Cycle, and decreased antioxidant levels. Consequences of chronically activated O&NS and immune-inflammatory pathways in ME/CFS are brain disorders, including neuroinflammation and brain hypometabolism / hypoperfusion, toxic effects of nitric oxide and peroxynitrite, lipid peroxidation and oxidative damage to DNA, secondary autoimmune responses directed against disrupted lipid membrane components and proteins, mitochondrial dysfunctions with a disruption of energy metabolism (e.g. compromised ATP production) and dysfunctional intracellular signaling pathways. The interplay between all of these factors leads to self-amplifying feed forward loops causing a chronic state of activated O&NS, immune-inflammatory and autoimmune pathways which may sustain the disease.
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Affiliation(s)
| | - Michael Maes
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand ; Department of Psychiatry, Deakin University, Geelong, Australia
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Morris G, Maes M. Myalgic encephalomyelitis/chronic fatigue syndrome and encephalomyelitis disseminata/multiple sclerosis show remarkable levels of similarity in phenomenology and neuroimmune characteristics. BMC Med 2013; 11:205. [PMID: 24229326 PMCID: PMC3847236 DOI: 10.1186/1741-7015-11-205] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 08/15/2013] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND 'Encephalomyelitis disseminata' (multiple sclerosis) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are both classified as diseases of the central nervous system by the World Health Organization. This review aims to compare the phenomenological and neuroimmune characteristics of MS with those of ME/CFS. DISCUSSION There are remarkable phenomenological and neuroimmune overlaps between both disorders. Patients with ME/CFS and MS both experience severe levels of disabling fatigue and a worsening of symptoms following exercise and resort to energy conservation strategies in an attempt to meet the energy demands of day-to-day living. Debilitating autonomic symptoms, diminished cardiac responses to exercise, orthostatic intolerance and postural hypotension are experienced by patients with both illnesses. Both disorders show a relapsing-remitting or progressive course, while infections and psychosocial stress play a large part in worsening of fatigue symptoms. Activated immunoinflammatory, oxidative and nitrosative (O+NS) pathways and autoimmunity occur in both illnesses. The consequences of O+NS damage to self-epitopes is evidenced by the almost bewildering and almost identical array of autoantibodies formed against damaged epitopes seen in both illnesses. Mitochondrial dysfunctions, including lowered levels of ATP, decreased phosphocreatine synthesis and impaired oxidative phosphorylation, are heavily involved in the pathophysiology of both MS and ME/CFS. The findings produced by neuroimaging techniques are quite similar in both illnesses and show decreased cerebral blood flow, atrophy, gray matter reduction, white matter hyperintensities, increased cerebral lactate and choline signaling and lowered acetyl-aspartate levels. SUMMARY This review shows that there are neuroimmune similarities between MS and ME/CFS. This further substantiates the view that ME/CFS is a neuroimmune illness and that patients with MS are immunologically primed to develop symptoms of ME/CFS.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Pembrey, Llanelli, UK
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand
| | - Michael Maes
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand
- Department of Psychiatry, Deakin University, Geelong, Australia
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Coenzyme Q10 depletion in medical and neuropsychiatric disorders: potential repercussions and therapeutic implications. Mol Neurobiol 2013; 48:883-903. [PMID: 23761046 DOI: 10.1007/s12035-013-8477-8] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Accepted: 05/29/2013] [Indexed: 12/18/2022]
Abstract
Coenzyme Q10 (CoQ10) is an antioxidant, a membrane stabilizer, and a vital cofactor in the mitochondrial electron transport chain, enabling the generation of adenosine triphosphate. It additionally regulates gene expression and apoptosis; is an essential cofactor of uncoupling proteins; and has anti-inflammatory, redox modulatory, and neuroprotective effects. This paper reviews the known physiological role of CoQ10 in cellular metabolism, cell death, differentiation and gene regulation, and examines the potential repercussions of CoQ10 depletion including its role in illnesses such as Parkinson's disease, depression, myalgic encephalomyelitis/chronic fatigue syndrome, and fibromyalgia. CoQ10 depletion may play a role in the pathophysiology of these disorders by modulating cellular processes including hydrogen peroxide formation, gene regulation, cytoprotection, bioenegetic performance, and regulation of cellular metabolism. CoQ10 treatment improves quality of life in patients with Parkinson's disease and may play a role in delaying the progression of that disorder. Administration of CoQ10 has antidepressive effects. CoQ10 treatment significantly reduces fatigue and improves ergonomic performance during exercise and thus may have potential in alleviating the exercise intolerance and exhaustion displayed by people with myalgic encepholamyletis/chronic fatigue syndrome. Administration of CoQ10 improves hyperalgesia and quality of life in patients with fibromyalgia. The evidence base for the effectiveness of treatment with CoQ10 may be explained via its ability to ameliorate oxidative stress and protect mitochondria.
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Morris G, Anderson G, Galecki P, Berk M, Maes M. A narrative review on the similarities and dissimilarities between myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and sickness behavior. BMC Med 2013; 11:64. [PMID: 23497361 PMCID: PMC3751187 DOI: 10.1186/1741-7015-11-64] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 03/08/2013] [Indexed: 12/14/2022] Open
Abstract
It is of importance whether myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a variant of sickness behavior. The latter is induced by acute infections/injury being principally mediated through proinflammatory cytokines. Sickness is a beneficial behavioral response that serves to enhance recovery, conserves energy and plays a role in the resolution of inflammation. There are behavioral/symptomatic similarities (for example, fatigue, malaise, hyperalgesia) and dissimilarities (gastrointestinal symptoms, anorexia and weight loss) between sickness and ME/CFS. While sickness is an adaptive response induced by proinflammatory cytokines, ME/CFS is a chronic, disabling disorder, where the pathophysiology is related to activation of immunoinflammatory and oxidative pathways and autoimmune responses. While sickness behavior is a state of energy conservation, which plays a role in combating pathogens, ME/CFS is a chronic disease underpinned by a state of energy depletion. While sickness is an acute response to infection/injury, the trigger factors in ME/CFS are less well defined and encompass acute and chronic infections, as well as inflammatory or autoimmune diseases. It is concluded that sickness behavior and ME/CFS are two different conditions.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Bryn Road Seaside 87, Llanelli, SA152LW, UK
| | - George Anderson
- CRC Clinical Research Centre/Communications, Laurel Street 57, Glasgow, G11 7QT,UK
| | - Piotr Galecki
- Department of Adult Psychiatry, Medical University of Lodz, Aleksandrowska 159, Lodz, 91229, Poland
| | - Michael Berk
- Barwon Health, School of Medicine, Deakin University, PO Box 291, Geelong, 3220, Australia
- Orygen Youth Health Research Centre, Poplar Road 35, Parkville, 3052, Australia
- Centre of Youth Mental Health, University of Melbourne, Poplar Road 35, Parkville, 3052, Australia
- The Florey Institute for Neuroscience and Mental Health, University of Melbourne, Kenneth Myer Building, Royal Parade 30, Parkville, 3052, Australia
- Department of Psychiatry, University of Melbourne, Level 1 North, Main Block, Royal Melbourne Hospital, Parkville, 3052, Australia
| | - Michael Maes
- Barwon Health, School of Medicine, Deakin University, PO Box 291, Geelong, 3220, Australia
- Department of Psychiatry, Chulalongkorn University, Rama 4 Road 1873, Pathumwan, Bangkok, 10330, Thailand
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Hooper PL, Hightower LE, Hooper PL. Loss of stress response as a consequence of viral infection: implications for disease and therapy. Cell Stress Chaperones 2012; 17:647-55. [PMID: 22797944 PMCID: PMC3468676 DOI: 10.1007/s12192-012-0352-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 07/02/2012] [Accepted: 07/03/2012] [Indexed: 02/08/2023] Open
Abstract
Herein, we propose that viral infection can induce a deficient cell stress response and thereby impairs stress tolerance and makes tissues vulnerable to damage. Having a valid paradigm to address the pathological impacts of viral infections could lead to effective new therapies for diseases that have previously been unresponsive to intervention. Host response to viral infections can also lead to autoimmune diseases like type 1 diabetes. In the case of Newcastle disease virus, the effects of viral infection on heat shock proteins may be leveraged as a therapy for cancer. Finally, the search for a specific virus being responsible for a condition like chronic fatigue syndrome may not be worthwhile if the disease is simply a nonspecific response to viral infection.
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Affiliation(s)
- Philip L Hooper
- Division of Endocrinology, Metabolism, and Diabetes, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA.
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