Biological underpinnings of the commonalities in depression, somatization, and Chronic Fatigue Syndrome

Abstract:

BACKGROUND: Somatization is a multisomatoform disorder characterized by medically unexplained, functional or psychosomatic symptoms. Similar somatic symptoms are key components of depression and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

METHODS: This paper reviews the evidence that such symptoms are organically based. We use the term “physio-somatic” to describe these symptoms.

RESULTS: Inflammation, cell-mediated immune (CMI) activation and alterations in the tryptophan catabolite (TRYCAT) pathway are associated with the physio-somatic symptoms of depression, ME/CFS and/or somatization. Proinflammatory cytokines, decreased tryptophan and aberrations in TRYCATs may cause physio-somatic symptoms, such as fatigue, autonomic symptoms, hyperalgesia and somatic presentations.

CONCLUSIONS: The data suggest co-ordinated and interacting biological pathways driving the occurrence of physio-somatic symptoms across these three disorders, giving a biologically validated “pathway phenotype”. These data have far-reaching implications for DSM-IV diagnostic conceptualizations of somatization (and ME/CFS) suggesting the presence of an emerging organic explanation. Future research should focus on the role of immune regulation, and co-ordination, of neuronal activity and, through larger data sets, ultimately creating new, biologically validated classification rules. These data have implications for the development of novel therapies utilizing these insights, buttressing the role of psychotherapy in psychosomatic presentations.

Copyright © 2012 Elsevier Ltd. All rights reserved.

 

Source: Anderson G, Maes M, Berk M. Biological underpinnings of the commonalities in depression, somatization, and Chronic Fatigue Syndrome. Med Hypotheses. 2012 Jun;78(6):752-6. doi: 10.1016/j.mehy.2012.02.023. Epub 2012 Mar 23. https://www.ncbi.nlm.nih.gov/pubmed/22445460

 

Evidence for inflammation and activation of cell-mediated immunity in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): increased interleukin-1, tumor necrosis factor-α, PMN-elastase, lysozyme and neopterin

Abstract:

BACKGROUND: There is evidence that inflammatory pathways and cell-mediated immunity (CMI) play an important role in the pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Activation of inflammatory and CMI pathways, including increased levels of cytokines, is known to induce fatigue and somatic symptoms. Given the broad spectrum inflammatory state in ME/CFS, the aim of this study was to examine whether inflammatory and CMI biomarkers are increased in individuals with ME/CFS.

METHODS: In this study we therefore measured plasma interleukin-(IL)1, tumor necrosis factor (TNF)α, and PMN-elastase, and serum neopterin and lysozyme in 107 patients with ME/CFS, 37 patients with chronic fatigue (CF), and 20 normal controls. The severity of ME/CFS was measured with the Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale.

RESULTS: Serum IL-1, TNFα, neopterin and lysozyme are significantly higher in patients with ME/CFS than in controls and CF patients. Plasma PMN-elastase is significantly higher in patients with ME/CFS than in controls and CF patients and higher in the latter than in controls. Increased IL-1 and TNFα are significantly correlated with fatigue, sadness, autonomic symptoms, and a flu-like malaise; neopterin is correlated with fatigue, autonomic symptoms, and a flu-like malaise; and increased PMN-elastase is correlated with concentration difficulties, failing memory and a subjective experience of infection.

CONCLUSIONS: The findings show that ME/CFS is characterized by low-grade inflammation and activation of CMI. The results suggest that characteristic symptoms of ME/CFS, such as fatigue, autonomic symptoms and a flu-like malaise, may be caused by inflammatory mediators, e.g. IL-1 and TNFα.

Copyright © 2011 Elsevier B.V. All rights reserved.

 

Source: Maes M, Twisk FN, Kubera M, Ringel K. Evidence for inflammation and activation of cell-mediated immunity in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): increased interleukin-1, tumor necrosis factor-α, PMN-elastase, lysozyme and neopterin. J Affect Disord. 2012 Feb;136(3):933-9. doi: 10.1016/j.jad.2011.09.004. Epub 2011 Oct 4. https://www.ncbi.nlm.nih.gov/pubmed/21975140

 

Increased IgA responses to the LPS of commensal bacteria is associated with inflammation and activation of cell-mediated immunity in chronic fatigue syndrome

Abstract:

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is accompanied by a) systemic IgA/IgM responses against the lipopolysaccharides (LPS) of commensal bacteria; b) inflammation, e.g. increased plasma interleukin-(IL)1 and tumor necrosis factor (TNF)α; and c) activation of cell-mediated immunity (CMI), as demonstrated by increased neopterin.

METHODS: To study the relationships between the IgA/IgM responses to the LPS of microbiota, inflammation, CMI and the symptoms of ME/CFS we measured the IgA/IgM responses to the LPS of 6 different enterobacteria, serum IL-1, TNFα, neopterin, and elastase in 128 patients with ME/CFS and chronic fatigue (CF). Severity of symptoms was assessed by the Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale.

RESULTS: Serum IL-1, TNFα, neopterin and elastase are significantly higher in patients with ME/CFS than in CF patients. There are significant and positive associations between the IgA responses to LPS and serum IL-1, TNFα, neopterin and elastase. Patients with an abnormally high IgA response show increased serum IL-1, TNFα and neopterin levels, and higher ratings on irritable bowel syndrome (IBS) than subjects with a normal IgA response. Serum IL-1, TNFα and neopterin are significantly related to fatigue, a flu-like malaise, autonomic symptoms, neurocognitive disorders, sadness and irritability.

CONCLUSIONS: The findings show that increased IgA responses to commensal bacteria in ME/CFS are associated with inflammation and CMI activation, which are associated with symptom severity. It is concluded that increased translocation of commensal bacteria may be responsible for the disease activity in some ME/CFS patients.

Copyright © 2011 Elsevier B.V. All rights reserved.

 

Source: Maes M, Twisk FN, Kubera M, Ringel K, Leunis JC, Geffard M. Increased IgA responses to the LPS of commensal bacteria is associated with inflammation and activation of cell-mediated immunity in chronic fatigue syndrome. J Affect Disord. 2012 Feb;136(3):909-17. doi: 10.1016/j.jad.2011.09.010. Epub 2011 Oct 2. https://www.ncbi.nlm.nih.gov/pubmed/21967891

 

Activation of cell-mediated immunity in depression: association with inflammation, melancholia, clinical staging and the fatigue and somatic symptom cluster of depression

Abstract:

BACKGROUND: Depression is characterized by activation of cell-mediated immunity (CMI), including increased neopterin levels, and increased pro-inflammatory cytokines (PICs), such as interleukin-1 (IL-1) and tumor necrosis factor-α (TNFα). These PICs may induce depressive, melancholic and chronic fatigue (CF) symptoms.

METHODS: We examined serum neopterin and plasma PIC levels in depressive subgroups in relation to the depressive subtypes and the melancholic and CF symptoms of depression. Participants were 85 patients with depression and in 26 normal controls. Severity of depression was assessed with the Hamilton Depression Rating Scale (HDRS) and severity of CF with the Fibromyalgia and Chronic Fatigue Syndrome (FF) Rating Scale.

RESULTS: Serum neopterin was significantly higher in depressed patients and in particular in those with melancholia. There were positive correlations between serum neopterin, the plasma PICs and the number of previous depressive episodes. Neopterin and TNFα were associated with melancholia, while both PICs were associated with CF. Melancholia-group membership was predicted by the HDRS and neopterin, and CF group membership by age, the FF score and serum TNFα.

DISCUSSION: Depression and melancholia are accompanied by CMI activation, suggesting that neopterin plays a role in their pathophysiology, e.g. through activation of oxidative and nitrosative stress and apoptosis pathways. The intertwined CMI and inflammatory responses are potentially associated with the onset of depression and with the melancholic and CF symptoms of depression. Exposure to previous depressive episodes may magnify the size of CMI and PIC responses, possibly increasing the likelihood of new depressive episodes. CMI activation and inflammation may contribute to the staging or recurrence of depression.

Copyright © 2011 Elsevier Inc. All rights reserved.

 

Source: Maes M, Mihaylova I, Kubera M, Ringel K. Activation of cell-mediated immunity in depression: association with inflammation, melancholia, clinical staging and the fatigue and somatic symptom cluster of depression. Prog Neuropsychopharmacol Biol Psychiatry. 2012 Jan 10;36(1):169-75. doi: 10.1016/j.pnpbp.2011.09.006. Epub 2011 Sep 16. https://www.ncbi.nlm.nih.gov/pubmed/21945535

 

Lower whole blood glutathione peroxidase (GPX) activity in depression, but not in myalgic encephalomyelitis / chronic fatigue syndrome: another pathway that may be associated with coronary artery disease and neuroprogression in depression

Abstract:

BACKGROUND: Major depression and myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) are two disorders accompanied by an upregulation of the inflammatory and oxidative and nitrosative (IO&NS) pathways and a decreased antioxidant status. Moreover, depression is accompanied by disorders in inflammatory and neuroprogressive (IN-PRO) pathways.

METHODS: This study examines whole blood glutathione peroxidase (GPX) in depression and in ME/CFS; GPX is an enzyme that reduces hydroperoxides by oxidizing glutathione and consequently protects the cells from oxidative damage. Blood was sampled in 39 patients with depression, 40 patients with ME/CFS and 24 normal volunteers. Whole blood was analysed for GPX activity using the Ransel assay (Randox). Severity of illness was measured by means of the Hamilton Depression Rating Scale (HDRS) and the Fibromyalgia and Chronic Fatigue Syndrome Rating Scale (FF scale).

RESULTS: We found that whole blood GPX activity was significantly (p=0.001) lower in depressed patients than in normal controls and that there were no significant differences between ME/CFS and controls. In depression and ME/CFS, there were significant and inverse relationships between GPX activity and the FF items, depressed mood and autonomic symptoms. In depression, there were significant and negative correlations between whole blood GPX and the HDRS score and autonomic symptoms.

DISCUSSION: The results show that lowered whole blood GPX activity contributes to the lowered antioxidant status in depression. Since GPX activity is a predictor of neuroprogression and coronary artery disease (CAD), lowered GPX activity in depression contributes to the IN-PRO pathways and the comorbidity between depression and CAD. Our results suggest that patients with depression would benefit from Ebselen or a supplementation with glutathione, N-Acetyl-l-Cysteine and selenium.

 

Source: Maes M, Mihaylova I, Kubera M, Uytterhoeven M, Vrydags N, Bosmans E. Lower whole blood glutathione peroxidase (GPX) activity in depression, but not in myalgic encephalomyelitis / chronic fatigue syndrome: another pathway that may be associated with coronary artery disease and neuroprogression in depression. Neuro Endocrinol Lett. 2011;32(2):133-40. https://www.ncbi.nlm.nih.gov/pubmed/21552194

Amitriptyline and prochlorperazine inhibit proinflammatory mediator release from human mast cells: possible relevance to chronic fatigue syndrome

CFS a complex disorder characterized by unexplained severe fatigue for over 6 months with a broad range of additional symptoms involving the nervous, endocrine and immune systems, and an estimated prevalence of 1%1. Tricyclic antidepressants (TCAs) are prescribed off label for a number of painful diseases that are often comorbid, such as chronic fatigue syndrome (CFS), fibromyalgia, interstitial cystitis, and irritable bowel syndrome, the symptoms of which are worsened by stress2. However, there is no known mechanism to explain the apparent beneficial action of TCAs3.

Mast cells and their mediators have been implicated in inflammatory diseases4, including CFS5. Mast cells are located perivascularly in close proximity to neurons in the thalamus and hypothalamus, especially the median eminence6, where they are juxtaposed to corticotropin-releasing hormone (CRH)-positive nerve processes7. CRH activates mast cells to release vascular endothelial growth factor (VEGF)8, which could participate in neurogenic inflammation and contribute to the pathogenesis of CFS. Such mediators may be released locally in the brain or may cross the blood-brain-barrier (BBB), which can be disrupted by stress, subsequent to mast cell activation9. Given the above, we hypothesized that TCAs may be helpful through inhibition of mast cell release of pro-inflammatory mediators.

You can read the rest of this letter here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498825/

 

Source: Clemons A, Vasiadi M, Kempuraj D, Kourelis T, Vandoros G, Theoharides TC. Amitriptyline and prochlorperazine inhibit proinflammatory mediator release from human mast cells: possible relevance to chronic fatigue syndrome. J Clin Psychopharmacol. 2011 Jun;31(3):385-7. doi: 10.1097/JCP.0b013e3182196e50. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498825/ (Full article)

 

Chronic fatigue syndrome–a neuroimmunological model

Abstract:

The aetiological and pathophysiological basis of chronic fatigue syndrome (CFS) remains a controversial field of inquiry in the research community. While CFS and similar disease conditions such as fibromyalgia (FM) and post-infectious encephalopathy have been the focus of intense scrutiny for the past 20 years, results of research were often contradictory and a cohesive pathological model has remained elusive. However, recent developments in understanding the unique immunophysiology of the brain may provide important clues for the development of a truly comprehensive explanation of the pathology of CFS.

We argue that CFS pathogenesis lies in the influence of peripheral inflammatory events on the brain and the unique immunophysiology of the central nervous system. There is also evidence that CFS patients have a relative immunodeficiency that predisposes to poor early control of infection that leads to chronic inflammatory responses to infectious insults.

The neurological and endocrine changes have been described in CFS patients support the view that CFS has an inflammatory pathogenesis when considered as a whole. An inflammatory model of disease also provides an explanation for the marked female sex bias associated with CFS.

This review therefore posits the hypothesis that CFS as a disease of long-term inflammatory processes of the brain. We will also provide an investigative framework that could be used to justify the use of anti-TNF biological agents as a reliable and effective treatment approach to CFS, a syndrome that to date remains frustratingly difficult for both patients and health care professionals to manage.

Copyright © 2011 Elsevier Ltd. All rights reserved.

 

Source: Arnett SV, Alleva LM, Korossy-Horwood R, Clark IA. Chronic fatigue syndrome–a neuroimmunological model. Med Hypotheses. 2011 Jul;77(1):77-83. doi: 10.1016/j.mehy.2011.03.030. Epub 2011 Apr 6. https://www.ncbi.nlm.nih.gov/pubmed/21474251

 

Will vitamin D supplementation ameliorate diseases characterized by chronic inflammation and fatigue?

Abstract:

Chronic NF-κB activation has been supposed as a key event in chronic fatigue syndrome (CFS) and many other better-defined pro-inflammatory diseases. Knowledge about the impact of deficiency vitamin D on chronic NF-κB activation could open a new disease approach. Whereas NF-κB activation leads at first to a pro-inflammatory immune response, later on a vitamin D-dependent anti-inflammatory response ensues. Binding of the active vitamin D metabolite 1,25(OH)(2)D(3) to vitamin D receptor (VDR) yields a transcription factor which represses NF-κB activation, and additionally modulates and down-regulates adaptive, but enhances innate immune responses, and improves redox balance, thus counterbalancing inflammation on multiple levels. However, this built-in late counterbalance against inflammation works only when stores of calcium and 25(OH)D(3) are abundant. Therefore a connection between lowered vitamin D-metabolism and persistent NF-κB activation, augmented nitrosative-oxidative stress, redox imbalance, chronic inflammation, and concomitant fatigue can be postulated. In order to confirm this hypothesis, randomized controlled clinical studies about the clinical effects of supplementation of calcium and vitamin D(3) would be necessary in diseases characterized by persistent NF-κB activation and chronic inflammation and fatigue.

Copyright © 2010 Elsevier Ltd. All rights reserved.

 

Source: Hoeck AD, Pall ML. Will vitamin D supplementation ameliorate diseases characterized by chronic inflammation and fatigue? Med Hypotheses. 2011 Feb;76(2):208-13. doi: 10.1016/j.mehy.2010.09.032. Epub 2010 Oct 25. https://www.ncbi.nlm.nih.gov/pubmed/20980105

 

Gut inflammation in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disease characterized by unexplained disabling fatigue and a combination of accompanying symptoms the pathology of which is incompletely understood.

Many CFS patients complain of gut dysfunction. In fact, patients with CFS are more likely to report a previous diagnosis of irritable bowel syndrome (IBS), a common functional disorder of the gut, and experience IBS-related symptoms. Recently, evidence for interactions between the intestinal microbiota, mucosal barrier function, and the immune system have been shown to play a role in the disorder’s pathogenesis.

Studies examining the microecology of the gastrointestinal (GI) tract have identified specific microorganisms whose presence appears related to disease; in CFS, a role for altered intestinal microbiota in the pathogenesis of the disease has recently been suggested. Mucosal barrier dysfunction promoting bacterial translocation has also been observed. Finally, an altered mucosal immune system has been associated with the disease.

In this article, we discuss the interplay between these factors in CFS and how they could play a significant role in GI dysfunction by modulating the activity of the enteric nervous system, the intrinsic innervation of the gut. If an altered intestinal microbiota, mucosal barrier dysfunction, and aberrant intestinal immunity contribute to the pathogenesis of CFS, therapeutic efforts to modify gut microbiota could be a means to modulate the development and/or progression of this disorder.

For example, the administration of probiotics could alter the gut microbiota, improve mucosal barrier function, decrease pro-inflammatory cytokines, and have the potential to positively influence mood in patients where both emotional symptoms and inflammatory immune signals are elevated. Probiotics also have the potential to improve gut motility, which is dysfunctional in many CFS patients.

 

Source: Lakhan SE, Kirchgessner A. Gut inflammation in chronic fatigue syndrome. Nutr Metab (Lond). 2010 Oct 12;7:79. doi: 10.1186/1743-7075-7-79. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2964729/ (Full article)

 

A Comparison of Immune Functionality in Viral versus Non-Viral CFS Subtypes

Abstract:

Participants with CFS were grouped into viral and non-viral onset fatigue categories and assessed for differential immunological marker expression. Peripheral Blood Mononuclear Cells were assessed for differential phenotypic expression of surface adherence glycoproteins on circulating lymphocytes. The flow cytometric analysis employed fluorescent monoclonal antibody labeling.

The viral in comparison to the non-viral group demonstrated significant elevations in several Th1 type subsets including: the percentage and number of CD4+ cells, the percentage and number of CD2+CD26+ cells, the percentage and number of CD2+CD4+CD26+ cells, the percentage and number of CD4+ CD26+ cells, and the percentage of Th2 naïve cells (CD4+ CD45RA+CD62L+).

Of the remaining significant findings, the non viral group demonstrated significant elevations in comparison to the viral group for the following Th1 type subsets: the percentage of CD8+ cells, the percentage of T-cytotoxic suppressor cells (CD3+8+), and the percentage and number of Th1 memory cells (CD8+CD45RA-CD62L-).

The viral group demonstrated a pattern of activation that differed from that of the group with a non-viral etiology, as evidenced by an elevated and out of range percentage and number of CD4+ cells, the percentage of CD2+CD26+, and the percentage of Th2 naïve cells (CD4+CD45RA+CD62L+). Both groups demonstrated reduced and out of range Natural Killer Cell Cytotoxicity and percentage of B-1 cells (CD5+CD19).

In addition, both groups demonstrated an elevated and out of range percentage of CD2+CD8+CD26+, percentage of the Th1 memory subset (CD4+CD45RA-CD62L-), the percentage of Th1 memory and naïve cells (CD8+CD45RA-CD62L-, CD8+CD45RA+CD62L-), the percentage and number of Th2 memory cells (CD4+CD45RA-CD62L+), and the percentage of Th2 memory and naïve cells (CD8+CD45RA-CD62L+, CD8+CD45RA+CD62L+).

These findings imply that the homeostatic mechanism responsible for the regulation of the Th1 (cell mediated) and Th2 (humoral) immune responses is disturbed in CFS. The implications of these findings are discussed.

 

Source: Porter N, Lerch A, Jason LA, Sorenson M, Fletcher MA, Herrington J. A Comparison of Immune Functionality in Viral versus Non-Viral CFS Subtypes. J Behav Neurosci Res. 2010 Jun 1;8(2):1-8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3951052/ (Full article)