Tag: microbiome

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 panel of biomarkers accurately identifies CFS/ME patients and contributes to the understanding of the pathophysiology of the disorder

Abstract: 

Background: CFS/ME is a debilitating illness for which no specific biomarkers have been identified, although several immune abnormalities including neuroinflammation have been described. The goal of this study was to assemble a panel of immune and inflammatory markers, with the ability to accurately identify CFS/ME cases.

Objectives: From observations made in clinical practice, four markers were selected (immune and inflammatory). These markers were initially investigated to establish differences between CFS/ME cases and controls. We then evaluated their potential usefulness as a diagnostic biomarker by establishing their specificity and sensitivity.

Methods: Venous blood was collected from 70 male and 70 female CFS/ME patients (mean age 43 and 44 years, respectively – Fukuda case definition was used) as well as 70 male and 70 female healthy controls (mean age 43.5 and 44.5 years, respectively).

Serum Interleukin 8 (IL-8), soluble CD14 (sCD14, a surrogate marker for bacterial LPS), and prostaglandin E2 (PGE2) were measured for all subjects as were absolute CD3- / CD57+ lymphocytes counts (CD57+ lymph), according to accepted clinical laboratory techniques.

We then established median values for all analysed parameters; independent sample t-test, Mann-Whitney test and ROC curve analysis were used to investigate difference linked to gender and age.

Results: ROC Statistics (area under the ROC curve) revealed a significant difference between CFS/ME cases and controls (p <0.001) for the four parameters separately, both in the male and female cohorts. Sensitivity was 74.3 – 80 % (females) and 52.1 – 85.9 % (males). Specificity was 57.1 – 98.1 (females) and 65.7 – 88.6 (males).

Logistic regression analysis for the combination of parameters in our panel (IL-8, sCD14, PGE2 and CD57+ lymph) correctly predicted in 89.36 % of male CFS/ME cases and in 97.14 % of female CFS/ME cases.

Conclusions: This panel differentiates CFS/ME cases from controls with high sensitivity and specificity and therefore represents a potential tool in selecting CFS/ME subjects for clinical studies. Each of these four biological markers relate strongly to the disorder.

PGE2 activates dendritic cells and suppresses their ability to attract T cells. It also suppresses the function of macrophages and neutrophils as well as Th1, CTL-, NK-cell mediated type 1 immunity (e.g. CD3- / CD57+ lymphocytes). PGE2 additionally promotes Th2, Th17 and Tregs and also modulates chemokine production (e.g. IL-8).

When taken together, these data suggest that lipopolysaccharide (LPS), likely from gut bacteria, plays an important role in the pathophysiology of CFS/ME.

This screening panel represents an initial step toward identifying biomarkers to broadly diagnose subjects with CFS/ME.

Subsequent markers will be required to subcategorize CFS/ME subjects in order to tailor therapeutic solutions.

 

Source: Kenny L. De Meirleir1,2, Tatjana Mijatovic3, Eugene Bosmans3, Nossa Van den Vonder2, Vincent Lombardi1. A panel of biomarkers accurately identifies CFS/ME patients and contributes to the understanding of the pathophysiology of the disorder. Abstract from IACFS/ME Conference 2016 Program.

1. Nevada Center for Biomedical Research at University
of Nevada, Reno, USA
2. Himmunitas vzw, Brussels, Belgium
3. RED Laboratories NV, Zellik, Belgium

 

Increased d-lactic Acid intestinal bacteria in patients with chronic fatigue syndrome

Abstract:

Patients with chronic fatigue syndrome (CFS) are affected by symptoms of cognitive dysfunction and neurological impairment, the cause of which has yet to be elucidated. However, these symptoms are strikingly similar to those of patients presented with D-lactic acidosis.

A significant increase of Gram positive facultative anaerobic faecal microorganisms in 108 CFS patients as compared to 177 control subjects (p<0.01) is presented in this report. The viable count of D-lactic acid producing Enterococcus and Streptococcus spp. in the faecal samples from the CFS group (3.5 x 10(7) cfu/L and 9.8 x 10(7) cfu/L respectively) were significantly higher than those for the control group (5.0 x 10(6) cfu/L and 8.9 x 10(4) cfu/L respectively). Analysis of exometabolic profiles of Enterococcus faecalis and Streptococcus sanguinis, representatives of Enterococcus and Streptococcus spp. respectively, by NMR and HPLC showed that these organisms produced significantly more lactic acid (p<0.01) from (13)C-labeled glucose, than the Gram negative Escherichia coli. Further, both E. faecalis and S. sanguinis secrete more D-lactic acid than E. coli.

This study suggests a probable link between intestinal colonization of Gram positive facultative anaerobic D-lactic acid bacteria and symptom expressions in a subgroup of patients with CFS. Given the fact that this might explain not only neurocognitive dysfunction in CFS patients but also mitochondrial dysfunction, these findings may have important clinical implications.

 

Source: Sheedy JR, Wettenhall RE, Scanlon D, Gooley PR, Lewis DP, McGregor N, Stapleton DI, Butt HL, DE Meirleir KL. Increased d-lactic Acid intestinal bacteria in patients with chronic fatigue syndrome. In Vivo. 2009 Jul-Aug;23(4):621-8. http://iv.iiarjournals.org/content/23/4/621.long (Full article)

 

A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is complex illness of unknown etiology. Among the broad range of symptoms, many patients report disturbances in the emotional realm, the most frequent of which is anxiety. Research shows that patients with CFS and other so-called functional somatic disorders have alterations in the intestinal microbial flora. Emerging studies have suggested that pathogenic and non-pathogenic gut bacteria might influence mood-related symptoms and even behavior in animals and humans.

In this pilot study, 39 CFS patients were randomized to receive either 24 billion colony forming units of Lactobacillus casei strain Shirota (LcS) or a placebo daily for two months. Patients provided stool samples and completed the Beck Depression and Beck Anxiety Inventories before and after the intervention. We found a significant rise in both Lactobacillus and Bifidobacteria in those taking the LcS, and there was also a significant decrease in anxiety symptoms among those taking the probiotic vs controls (p = 0.01). These results lend further support to the presence of a gut-brain interface, one that may be mediated by microbes that reside or pass through the intestinal tract.

 

Source: Rao AV, Bested AC, Beaulne TM, Katzman MA, Iorio C, Berardi JM, Logan AC. A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome. Gut Pathog. 2009 Mar 19;1(1):6. doi: 10.1186/1757-4749-1-6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2664325/ (Full article)