Tag: 2018

Suicidal ideation in non-depressed individuals: The effects of a chronic, misunderstood illness

Abstract:

Chronic illness is a risk factor for suicide but is often explained with depression. Research has shown an increased suicide rate in patients with myalgic encephalomyelitis and chronic fatigue syndrome, but specific risk factors have been unexplored. We qualitatively analyzed responses from 29 patients who endorsed suicidal ideation but did not meet depression criteria.

Two themes were developed: (1) feeling trapped and (2) loss of self, loss of others, stigma and conflict. Myalgic encephalomyelitis and chronic fatigue syndrome caused patients severe disability, restructured their lives, and inflicted serious pain. Participants emphasized that they were not depressed, but felt trapped by the lack of treatments available.

Source: Devendorf AR, McManimen SL, Jason LA. Suicidal ideation in non-depressed individuals: The effects of a chronic, misunderstood illness. J Health Psychol. 2018 Jul 1:1359105318785450. doi: 10.1177/1359105318785450. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29992837

Reduced glycolytic reserve in isolated natural killer cells from Myalgic encephalomyelitis/chronic fatigue syndrome patients: A preliminary investigation

Abstract:

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is medically unexplained post-exertional fatigue associated with significant reduction in natural killer cell (NK) cytotoxicity activity. Cytotoxic activity relies on glycolytic flux and mitochondrial respiration to fulfill energetic cellular demands. While mitochondrial dysfunction has been reported in ME/CFS patients, no previous investigation has examined the bioenergetic profile of isolated NK cells from ME/CFS patients.

OBJECTIVE: This study was to determine the metabolic function in resting NK cells from ME/CFS patients.

METHOD: Six ME/CFS patients (aged 50.33±4.95) were age and sex-matched with non-fatigued healthy controls (aged 50.00±5.04). Mitochondrial stress tests measured parameters of mitochondrial function in the NK cells including basal respiration, ATP production, proton leak, maximal respiration, spare respiratory capacity and bioenergetic health index. Glycolytic stress tests measured parameters of glycolytic function such as glycolytic reserve, glycolysis and glycolytic capacity in isolated NK cells from ME/CFS patients and healthy controls using an extracellular flux analyzer, Seahorse XFp.

RESULT: There was a significant reduction of glycolytic reserve in resting NK cells from ME/CFS patients (0.6±0.07 mpH/ min) compared with healthy control (2.25±1.3 mpH/min). Mitochondrial respiration in resting NK cells did not approach statistical significance between ME/CFS patients and healthy controls.

CONCLUSION: These findings suggest resting NK cells from ME/CFS patients have reduced ability to increase glycolytic flux to respond to high energetic demands for ATP production. Hence, the reduced glycolytic reserves we have identified in isolated resting isolated NK cells should be further investigated to assist in understanding ME/CFS pathogenesis.

Source: Nguyen T, Staines D, Johnston S, Marshall-Gradisnik S. Reduced glycolytic reserve in isolated natural killer cells from Myalgic encephalomyelitis/chronic fatigue syndrome patients: A preliminary investigation. Asian Pac J Allergy Immunol. 2018 Jul 8. doi: 10.12932/AP-011117-0188. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29981562

Reduction of Glucocorticoid Receptor Function in Chronic Fatigue Syndrome

Abstract:

Glucocorticoid receptor (GR) function may have aetiopathogenic significance in chronic fatigue syndrome (CFS), via its essential role in mediating inflammatory responses as well as in hypothalamic-pituitary-adrenal axis regulation. GR function can be estimated ex vivo by measuring dexamethasone (dex) modulation of cytokine response to lipopolysaccharide (LPS), and in vivo using the impact of dex on cortisol levels. This study aimed to compare the GR function between CFS (n = 48), primary Sjögren’s syndrome (a disease group control) (n = 27), and sedentary healthy controls (HCs) (n = 20), and to investigate its relationship with clinical measures.

In the GR ex vivo response assay, whole blood was diluted and incubated with LPS (to stimulate cytokine production), with or without 10 or 100 nanomolar concentrations of dex. Cytometric bead array (CBA) and flow cytometry enabled quantification of cytokine levels (TNFα, interleukin- (IL-) 6, and IL-10) in the supernatants. In the in vivo response assay, five plasma samples were taken for determination of total cortisol concentration using ELISA at half-hourly intervals on two consecutive mornings separated by ingestion of 0.5 mg of dex at 11 pm. The association of the data from the in vivo and ex vivo analyses with reported childhood adversity was also examined.

CFS patients had reduced LPS-induced IL-6 and TNFα production compared to both control groups and reduced suppression of TNFα by the higher dose of dex compared to HCs. Cortisol levels, before or after dex, did not differ between CFS and HCs. Cortisol levels were more variable in CFS than HCs. In the combined group (CFS plus HC), cortisol concentrations positively and ex vivo GR function (determined by dex-mediated suppression of IL-10) negatively correlated with childhood adversity score.

The results do not support the hypothesis that GR dysregulation is aetiopathogenic in CFS and suggest that current and future endocrine cross-sectional studies in CFS may be vulnerable to the confounding influence of childhood trauma which is likely increased by comorbid depression.

Source: Lynn M, Maclachlan L, Finkelmeyer A, Clark J, Locke J, Todryk S, Ng WF, Newton JL, Watson S. Reduction of Glucocorticoid Receptor Function in Chronic Fatigue Syndrome. Mediators Inflamm. 2018 Jun 10;2018:3972104. doi: 10.1155/2018/3972104. eCollection 2018. https://www.ncbi.nlm.nih.gov/pubmed/29983634

Insights from metabolites get us closer to a test for chronic fatigue syndrome

Press Release: Columbia University’s Mailman School of Public Health, July 9, 2018. A study led by researchers at the Center for Infection and Immunity (CII) at Columbia University’s Mailman School of Public Health has identified a constellation of metabolites related to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Combining this data with data from an earlier microbiome study, the researchers now report they can predict whether or not someone has the disorder with a confidence of 84 percent.

The research team analyzed blood samples provided by 50 patients with ME/CFS and 50 controls matched for sex and age who were recruited at four clinical sites across the United States. Using mass spectrometry, a laboratory technique used to identify molecules by measuring their mass, the scientists found 562 metabolites — microscopic byproducts of human and microbial processes such as sugar, fat, and protein molecules. They excluded molecules related to antidepressants and other drugs patients might be taking.

Their metabolomics analysis, among the most detailed and meticulous to date, uncovered altered levels of metabolites, including choline, carnitine and several complex lipids present in patients with ME/CFS. The altered metabolites suggest dysfunction of the mitochrondria, the cellular powerplant, a finding in line with those reported by other research teams. Uniquely, the CII study also reports a second distinct pattern of metabolites in patients with ME/CFS and irritable bowel syndrome (IBS), matching earlier findings from their 2017 fecal microbiome study. Half of the patients with ME/CFS also had IBS.

When the researchers combined biomarkers from both the microbiome study and the new metabolome study, they reported a .836 predictive score, indicating an 84 percent certainty as to the presence of ME/CFS — better than with either study alone.

“This is a strong predictive model that suggests we’re getting close to the point where we’ll have lab tests that will allow us to say with a high level of certainty who has this disorder,” says first author Dorottya Nagy-Szakal, MD, PhD, a researcher at CII.

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Meta-analysis investigating post-exertional malaise between patients and controls

Abstract:

Post-exertional malaise is either required or included in many previously proposed case definitions of myalgic encephalomyelitis/chronic fatigue syndrome. A meta-analysis of odds ratios (ORs; association between patient status and post-exertional malaise status) and a number of potential moderators (i.e. study-level characteristics) of effect size were conducted.

Post-exertional malaise was found to be 10.4 times more likely to be associated with a myalgic encephalomyelitis/chronic fatigue syndrome diagnosis than with control status. Significant moderators of effect size included patient recruitment strategy and control selection. These findings suggest that post-exertional malaise should be considered a cardinal symptom of myalgic encephalomyelitis/chronic fatigue syndrome.

Source: Brown A, Jason LA. Meta-analysis investigating post-exertional malaise between patients and controls. J Health Psychol. 2018 Jul 1:1359105318784161. doi: 10.1177/1359105318784161. [Epub ahead of print]  https://www.ncbi.nlm.nih.gov/pubmed/29974812

Intracranial compliance is associated with symptoms of orthostatic intolerance in chronic fatigue syndrome

Abstract:

Symptoms of orthostatic intolerance (OI) are common in Chronic Fatigue Syndrome (CFS) and similar disorders. These symptoms may relate to individual differences in intracranial compliance and cerebral blood perfusion.

The present study used phase-contrast, quantitative flow magnetic resonance imaging (MRI) to determine intracranial compliance based on arterial inflow, venous outflow and cerebrospinal fluid flow along the spinal canal into and out of the cranial cavity. Flow-sensitive Alternating Inversion Recovery (FAIR) Arterial Spin Labelling was used to measure cerebral blood perfusion at rest.

Forty patients with CFS and 10 age and gender matched controls were scanned. Severity of symptoms of OI was determined from self-report using the Autonomic Symptom Profile. CFS patients reported significantly higher levels of OI (p < .001). Within the patient group, higher severity of OI symptoms were associated with lower intracranial compliance (r = -.346, p = .033) and higher resting perfusion (r = .337, p = .038). In both groups intracranial compliance was negatively correlated with cerebral perfusion. There were no significant differences between the groups in intracranial compliance or perfusion.

In patients with CFS, low intracranial compliance and high resting cerebral perfusion appear to be associated with an increased severity of symptoms of OI. This may signify alterations in the ability of the cerebral vasculature to cope with changes to systemic blood pressure due to orthostatic stress, but this may not be specific to CFS.

Source: Andreas Finkelmeyer, Jiabao He, Laura Maclachlan, Andrew M. Blamire, Julia L. Newton. Intracranial compliance is associated with symptoms of orthostatic intolerance in chronic fatigue syndrome. PLoS ONE. Published: July 3, 2018 https://doi.org/10.1371/journal.pone.0200068 (Full article)

Are ME/CFS Patient Organizations “Militant”?

Abstract:

Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) is a contested illness category. This paper investigates the common claim that patients with ME/CFS—and by extension, ME/CFS patient organizations (POs)—exhibit “militant” social and political tendencies. The paper opens with a history of the protracted scientific disagreement over ME/CFS. We observe that ME/CFS POs, medical doctors, and medical researchers exhibit clear differences in opinion over how to conceptualize this illness.

However, we identify a common trope in the discourse over ME/CFS: the claim of “militant” patient activism. Scrutinizing this charge, we find no compelling evidence that the vast majority of patients with ME/CFS, or the POs representing them, have adopted any such militant political policies or behaviours. Instead, we observe key strategic similarities between ME/CFS POs in the United Kingdom and the AIDs activist organizations of the mid-1980s in the United States which sought to engage scientists using the platform of public activism and via scientific publications.

Finally, we explore the contours of disagreement between POs and the medical community by drawing on the concept of epistemic injustice. We find that widespread negative stereotyping of patients and the marginalization and exclusion of patient voices by medical authorities provides a better explanation for expressions of frustration among patients with ME/CFS.

Source: Blease, C. & Geraghty, K.J. Are ME/CFS Patient Organizations “Militant”? Bioethical Inquiry (2018). https://doi.org/10.1007/s11673-018-9866-5

Insights into myalgic encephalomyelitis/chronic fatigue syndrome phenotypes through comprehensive metabolomics

Abstract:

The pathogenesis of ME/CFS, a disease characterized by fatigue, cognitive dysfunction, sleep disturbances, orthostatic intolerance, fever, irritable bowel syndrome (IBS), and lymphadenopathy, is poorly understood.

We report biomarker discovery and topological analysis of plasma metabolomic, fecal bacterial metagenomic, and clinical data from 50 ME/CFS patients and 50 healthy controls. We confirm reports of altered plasma levels of choline, carnitine and complex lipid metabolites and demonstrate that patients with ME/CFS and IBS have increased plasma levels of ceramide.

Integration of fecal metagenomic and plasma metabolomic data resulted in a stronger predictive model of ME/CFS (cross-validated AUC = 0.836) than either metagenomic (cross-validated AUC = 0.745) or metabolomic (cross-validated AUC = 0.820) analysis alone. Our findings may provide insights into the pathogenesis of ME/CFS and its subtypes and suggest pathways for the development of diagnostic and therapeutic strategies.

Source: Dorottya Nagy-Szakal, Dinesh K. Barupal, Bohyun Lee, Xiaoyu Che, Brent L. Williams, Ellie J. R. Kahn, Joy E. Ukaigwe, Lucinda Bateman, Nancy G. Klimas, Anthony L. Komaroff, Susan Levine, Jose G. Montoya, Daniel L. Peterson, Bruce Levin, Mady Hornig, Oliver Fiehn & W. Ian Lipkin . Insights into myalgic encephalomyelitis/chronic fatigue syndrome phenotypes through comprehensive metabolomics. Scientific Reports, volume 8, Article number: 10056 (2018) https://www.nature.com/articles/s41598-018-28477-9 (Full article)