Tag: Maes

The reification of the clinical diagnosis of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) as an immune and oxidative stress disorder: construction of a data-driven nomothethic network and exposure of ME/CFS subgroups

Abstract:

The approach towards myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) remains in a permanent state of crisis with fierce competition between the psychosocial school, which attributes ME/CFS to the perception of effort, and the medical approach (Maes and Twisk, BMC Med, 2010,8,35). The aim of this paper is to review how to construct a nomothetic model of ME/CFS using Partial Least Squares (PLS) path analysis and ensembling causome (bacterial translocation as assessed with IgM/IgA responses to LPS), protectome (lowered coenzyme Q10), adverse outcome pathways (AOP) including increased lysozyme, CD38+ T cell activation, cell-mediated immune activation (CMI), and IgM responses to oxidative specific epitopes and NO-adducts (IgM OSENO).

Using PLS, we trained, tested and validated this knowledge- and data-driven causal ME/CFS model, which showed adequate convergence, construct and replicability validity. This bottom-up explicit data model of ME/CFS objectivates the descriptive narratives of the ME/CFS phenome, using causome-protectome-AOP data, whereby the abstract concept ME/CFS is translated into pathways, thereby securing the reification of the ME/CFS phenome.

We found that 31.6% of the variance in the physiosomatic symptom dimension of ME/CFS was explained by the cumulative effects of CMI and CD38+ activation, IgM OSENO, IgA LPS, lysozyme (all positive) and coenzyme Q10 (inversely). Cluster analysis performed on the PLS-generated latent vector scores of all feature sets exposed three distinct immune groups of ME/CFS, namely one with increased lysozyme, one with increased CMI + CD38 activation + depressive symptoms, and another with increased bacterial translocation + autoimmune responses to OSENO

Source: Maes M, Kubera M, Stoyanova K, Leunis JC. The reification of the clinical diagnosis of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) as an immune and oxidative stress disorder: construction of a data-driven nomothethic network and exposure of ME/CFS subgroups. Curr Top Med Chem. 2021 Jul 27. doi: 10.2174/1568026621666210727170147. Epub ahead of print. PMID: 34315375. https://pubmed.ncbi.nlm.nih.gov/34315375/

Environmental, Neuro-immune, and Neuro-oxidative Stress Interactions in Chronic Fatigue Syndrome

Abstract:

Chronic fatigue syndrome/myalgic encephalomyelitis (CFS) is a complex, multisystem disease that is characterized by long-term fatigue, exhaustion, disabilities, pain, neurocognitive impairments, gastrointestinal symptoms, and post-exertional malaise, as well as lowered occupational, educational, and social functions. The clinical and biomarker diagnosis of this disorder is hampered by the lack of validated diagnostic criteria and laboratory tests with adequate figures of merit, although there are now many disease biomarkers indicating the pathophysiology of CFS.

Here, we review multiple factors, such as immunological and environmental factors, which are associated with CFS and evaluate current concepts on the involvement of immune and environmental factors in the pathophysiology of CFS. The most frequently reported immune dysregulations in CFS are modifications in immunoglobulin contents, changes in B and T cell phenotypes and cytokine profiles, and decreased cytotoxicity of natural killer cells. Some of these immune aberrations display a moderate diagnostic performance to externally validate the clinical diagnosis of CFS, including the expression of activation markers and protein kinase R (PKR) activity. Associated with the immune aberrations are activated nitro-oxidative pathways, which may explain the key symptoms of CFS.

This review shows that viral and bacterial infections, as well as nutritional deficiencies, may further aggravate the immune-oxidative pathophysiology of CFS. Targeted treatments with antioxidants and lipid replacement treatments may have some clinical efficacy in CFS. We conclude that complex interactions between immune and nitro-oxidative pathways, infectious agents, environmental factors, and nutritional deficiencies play a role in the pathophysiology of CFS.

Source: Bjørklund G, Dadar M, Pivina L, Doşa MD, Semenova Y, Maes M. Environmental, Neuro-immune, and Neuro-oxidative Stress Interactions in Chronic Fatigue Syndrome [published online ahead of print, 2020 Aug 6]. Mol Neurobiol. 2020;10.1007/s12035-020-01939-w. doi:10.1007/s12035-020-01939-w  https://pubmed.ncbi.nlm.nih.gov/32761353/

Mitochondria and Immunity in Chronic Fatigue Syndrome

Abstract:

It is widely accepted that the pathophysiology and treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) could be considerably improved. The heterogeneity of ME/CFS and the confusion over its classification have undoubtedly contributed to this, although this would seem a consequence of the complexity of the array of ME/CFS presentations and high levels of diverse comorbidities.

This article reviews the biological underpinnings of ME/CFS presentations, including the interacting roles of the gut microbiome/permeability, endogenous opioidergic system, immune cell mitochondria, autonomic nervous system, microRNA-155, viral infection/re-awakening and leptin as well as melatonin and the circadian rhythm. This details not only relevant pathophysiological processes and treatment options, but also highlights future research directions.

Due to the complexity of interacting systems in ME/CFS pathophysiology, clarification as to its biological underpinnings is likely to considerably contribute to the understanding and treatment of other complex and poorly managed conditions, including fibromyalgia, depression, migraine, and dementia. The gut and immune cell mitochondria are proposed to be two important hubs that interact with the circadian rhythm in driving ME/CFS pathophysiology.

Source: Anderson G, Maes M. Mitochondria and immunity in chronic fatigue syndrome [published online ahead of print, 2020 May 26]. Prog Neuropsychopharmacol Biol Psychiatry. 2020;109976. doi:10.1016/j.pnpbp.2020.109976 https://pubmed.ncbi.nlm.nih.gov/32470498/

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: From Pathophysiological Insights to Novel Therapeutic Opportunities

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.

Copyright © 2019. Published by Elsevier Ltd.

Source: Morris G, Puri BK, Walker AJ, Maes M, Carvalho AF, Walder K, Mazza C, Berk M. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: From Pathophysiological Insights to Novel Therapeutic Opportunities. Pharmacol Res. 2019 Sep 8:104450. doi: 10.1016/j.phrs.2019.104450. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31509764

Shared microglial mechanisms underpinning depression and chronic fatigue syndrome and their comorbidities

Abstract:

In 2011, it was reviewed that a) there is a strong co-occurrence between major depression and chronic fatigue syndrome (CFS), with fatigue and physio-somatic symptoms being key symptoms of depression, and depressive symptoms appearing during the course of CFS; and b) the comorbidity between both disorders may in part be explained by activated immune-inflammatory pathways, including increased translocation of Gram-negative bacteria and increased levels of pro-inflammatory cytokines, such as interleukin (IL)-1. Nevertheless, the possible involvement of activated microglia in this comorbidity has remained unclear.

This paper aims to review microglial disturbances in major depression, CFS and their comorbidity. A comprehensive literature search was conducted using the PubMed / MEDLINE database to identify studies, which are relevant to this current review. Depressed patients present neuroinflammatory alterations, probably related to microglial activation, while animal models show that a microglial response to immune challenges including lipopolysaccharides is accompanied by depressive-like behaviors. Recent evidence from preclinical studies indicates that activated microglia have a key role in the onset of fatigue. In chronic inflammatory conditions, such as infections and senescence, microglia orchestrate an inflammatory microenvironment thereby causing fatigue.

In conclusion, based on our review we may posit that shared immune-inflammatory pathways and especially activated microglia underpin comorbid depression and CFS. As such, microglial activation and neuro-inflammation may be promising targets to treat the overlapping manifestations of both depression and CFS.

Copyright © 2019. Published by Elsevier B.V.

Source: Filho AJMC, Macedo DS, de Lucena DF, Maes M. Shared microglial mechanisms underpinning depression and chronic fatigue syndrome and their comorbidities. Behav Brain Res. 2019 May 25:111975. doi: 10.1016/j.bbr.2019.111975. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31136774

Recognizing the leaky gut as a trans-diagnostic target for neuro-immune disorders using clinical chemistry and molecular immunology assays

Abstract:

BACKGROUND: Increased intestinal permeability with heightened translocation of Gram-negative bacteria, also known as “leaky gut”, is associated with the pathophysiology of neuroimmune disorders, such as major depressive disorder (MDD), chronic fatigue syndrome (CSF) and (deficit) schizophrenia, as well as with general medical disorders, including irritable bowel syndrome. This review aims to summarize clinical biochemistry and molecular immunology tests that may aid in the recognition of leaky gut in clinical practice.

METHODS: We searched online libraries, including PubMed/MEDLINE, Google Scholar and Scopus, with the key words “diagnosis” or “biomarkers” and “leaky gut”, “bacterial translocation”, and “intestinal permeability” and focused on papers describing tests that may aid in the clinical recognition of leaky gut.

RESULTS: To evaluate tight junction barrier integrity, serum IgG/IgA/IgM responses to occludin and zonulin and IgA responses to actomyosin should be evaluated. The presence of cytotoxic bacterial products in serum can be evaluated using IgA/IgM responses to sonicated samples of common Gram-negative gut commensal bacteria and assays of serum lipopolysaccharides (LPSs) and other bacterial toxins, including cytolethal distenting toxin, subunit B. Major factors associated with increased gut permeability, including gut dysbiosis and yeast overgrowth, use of NSAIDs and alcohol, food hypersensitivities (IgE-mediated), food intolerances (IgG-mediated), small bacterial overgrowth (SIBO), systemic inflammation, psychosocial stressors, some infections (e.g., HIV) and dietary patterns, should be assessed. Stool samples can be used to assay gut dysbiosis, gut inflammation and decreased mucosal defenses using assays of fecal growth of bacteria, yeast and fungi and stool assays of calprotectin, secretory IgA, β-defensin, α-antitrypsin, lysozyme and lactoferrin. Blood and breath tests should be used to exclude common causes of increased gut permeability, namely, food hypersensitivities and intolerances, SIBO, lactose intolerance and fructose malabsorption.

DISCUSSION: Here, we propose strategies to recognize “leaky gut” in a clinical setting using the most adequate clinical chemistry and molecular immunology assays.

Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Source: Simeonova D, Ivanovska M, Murdjeva M, Carvalho AF, Maes M. Recognizing the leaky gut as a trans-diagnostic target for neuro-immune disorders using clinical chemistry and molecular immunology assays. Curr Top Med Chem. 2018 Nov 14. doi: 10.2174/1568026618666181115100610. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/30430944

Mechanisms Explaining Muscle Fatigue and Muscle Pain in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a Review of Recent Findings

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.

 

Source: Gerwyn M, Maes M. 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 Jan;19(1):1. doi: 10.1007/s11926-017-0628-x. https://www.ncbi.nlm.nih.gov/pubmed/28116577

 

Hypothalamic-Pituitary-Adrenal Hypofunction in Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS) as a Consequence of Activated Immune-Inflammatory and Oxidative and Nitrosative Pathways

Abstract:

There is evidence that immune-inflammatory and oxidative and nitrosative stress (O&NS) pathways play a role in the pathophysiology of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS). There is also evidence that these neuroimmune diseases are accompanied by hypothalamic-pituitary-adrenal (HPA) axis hypoactivity as indicated by lowered baseline glucocorticoid levels.

This paper aims to review the bidirectional communications between immune-inflammatory and O&NS pathways and HPA axis hypoactivity in ME/CFS, considering two possibilities: (a) Activation of immune-inflammatory pathways is secondary to HPA axis hypofunction via attenuated negative feedback mechanisms, or (b) chronic activated immune-inflammatory and O&NS pathways play a causative role in HPA axis hypoactivity.

Electronic databases, i.e., PUBMED, Scopus, and Google Scholar, were used as sources for this narrative review by using keywords CFS, ME, cortisol, ACTH, CRH, HPA axis, glucocorticoid receptor, cytokines, immune, immunity, inflammation, and O&NS.

Findings show that activation of immune-inflammatory and O&NS pathways in ME/CFS are probably not secondary to HPA axis hypoactivity and that activation of these pathways may underpin HPA axis hypofunction in ME/CFS. Mechanistic explanations comprise increased levels of tumor necrosis factor-α, T regulatory responses with elevated levels of interleukin-10 and transforming growth factor-β, elevated levels of nitric oxide, and viral/bacterial-mediated mechanisms.

HPA axis hypoactivity in ME/CFS is most likely a consequence and not a cause of a wide variety of activated immune-inflammatory and O&NS pathways in that illness.

 

Source: Morris G, Anderson G, Maes M. Hypothalamic-Pituitary-Adrenal Hypofunction in Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS) as a Consequence of Activated Immune-Inflammatory and Oxidative and Nitrosative Pathways. Mol Neurobiol. 2016 Oct 20. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/27766535

 

The Role of Microbiota and Intestinal Permeability in the Pathophysiology of Autoimmune and Neuroimmune Processes with an Emphasis on Inflammatory Bowel Disease Type 1 Diabetes and Chronic Fatigue Syndrome

Abstract:

BACKGROUND: In steady state conditions intestinal immune homeostasis is maintained by a sophisticated bidirectional dialogue between the microbiota and the intestinal immune system. This “cross talk” is enabled by the presence of highly adapted secretory cells, sampling cells and pattern recognition receptors in the gastric epithelium.

METHODS: Herein we discuss the mechanisms involved in the breakdown of intestinal homeostasis and the development of systemic immune activation and neuroinflammation with a view to discussing the importance of these processes, in tandem with genetic and environmental factors, in the pathophysiology of (auto)immune diseases.Data is presented explaining how immune tolerance is maintained and how it may breakdown.

CONCLUSION: The breakdown of immune homeostasis following the development of gut inflammation, caused for example by gut dysbiosis, and the consequent increased intestinal permeability, is increasingly considered to be the ultimate source of the systemic immune activation and T helper 17/T regulatory cell imbalances, and maybe neurological disturbances, seen in autoimmune diseases such as Type 1 diabetes and inflammatory bowel disease. Increased intestinal permeability and translocation of commensal antigens into the systemic circulation is also a likely cause of the severe fatigue and an almost bewildering range of neurocognitive, neuroimaging and overall symptom presentations seen in patients with a diagnosis of Chronic Fatigue Syndrome.

 

Source: Morris G, Berk M, Carvalho AF, Caso JR, Sanz Y, Maes M. The Role of Microbiota and Intestinal Permeability in the Pathophysiology of Autoimmune and Neuroimmune Processes with an Emphasis on Inflammatory Bowel Disease Type 1 Diabetes and Chronic Fatigue Syndrome. Curr Pharm Des. 2016;22(40):6058-6075. https://www.ncbi.nlm.nih.gov/pubmed/27634186

 

Nitrosative Stress, Hypernitrosylation, and Autoimmune Responses to Nitrosylated Proteins: New Pathways in Neuroprogressive Disorders Including Depression and Chronic Fatigue Syndrome

Abstract:

Nitric oxide plays an indispensable role in modulating cellular signaling and redox pathways. This role is mainly effected by the readily reversible nitrosylation of selective protein cysteine thiols. The reversibility and sophistication of this signaling system is enabled and regulated by a number of enzymes which form part of the thioredoxin, glutathione, and pyridoxine antioxidant systems.

Increases in nitric oxide levels initially lead to a defensive increase in the number of nitrosylated proteins in an effort to preserve their function. However, in an environment of chronic oxidative and nitrosative stress (O&NS), nitrosylation of crucial cysteine groups within key enzymes of the thioredoxin, glutathione, and pyridoxine systems leads to their inactivation thereby disabling denitrosylation and transnitrosylation and subsequently a state described as “hypernitrosylation.”

This state leads to the development of pathology in multiple domains such as the inhibition of enzymes of the electron transport chain, decreased mitochondrial function, and altered conformation of proteins and amino acids leading to loss of immune tolerance and development of autoimmunity. Hypernitrosylation also leads to altered function or inactivation of proteins involved in the regulation of apoptosis, autophagy, proteomic degradation, transcription factor activity, immune-inflammatory pathways, energy production, and neural function and survival.

Hypernitrosylation, as a consequence of chronically elevated O&NS and activated immune-inflammatory pathways, can explain many characteristic abnormalities observed in neuroprogressive disease including major depression and chronic fatigue syndrome/myalgic encephalomyelitis. In those disorders, increased bacterial translocation may drive hypernitrosylation and autoimmune responses against nitrosylated proteins.

 

Source: Morris G, Berk M, Klein H, Walder K, Galecki P, Maes M. Nitrosative Stress, Hypernitrosylation, and Autoimmune Responses to Nitrosylated Proteins: New Pathways in Neuroprogressive Disorders Including Depression and Chronic Fatigue Syndrome. Mol Neurobiol. 2016 Jun 23. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/27339878