Altered serum bile acid profile in fibromyalgia is associated with specific gut microbiome changes and symptom severity

Abstract:

Alterations in the composition and function of the gut microbiome in women with fibromyalgia have recently been demonstrated, including changes in the relative abundance of certain bile acid metabolizing bacteria. Bile acids can affect multiple physiological processes, including visceral pain, but have yet to be explored for association to the fibromyalgia gut microbiome. In this study, 16S rRNA sequencing and targeted metabolomic approaches were used to characterize the gut microbiome and circulating bile acids in a cohort of 42 women with fibromyalgia and 42 healthy controls.

Alterations in the relative abundance of several bacterial species known to metabolize bile acids were observed in women with fibromyalgia, accompanied by significant alterations in the serum concentration of secondary bile acids, including a marked depletion of α-muricholic acid. Statistical learning algorithms could accurately detect individuals with fibromyalgia using the concentration of these serum bile acids. Serum α-muricholic acid was highly correlated with symptom severity, including pain intensity and fatigue.

Taken together, these findings suggest serum bile acid alterations are implicated in nociplastic pain. The changes observed in the composition of the gut microbiota and the concentration of circulating secondary bile acids seem congruent with the phenotype of increased nociception, and are quantitatively correlated with symptom severity.

This is a first demonstration of circulating bile acid alteration in individuals with fibromyalgia, potentially secondary to upstream gut microbiome alterations. If corroborated in independent studies, these observations may allow for the development of molecular diagnostic aids for fibromyalgia as well as mechanistic insights into the syndrome.

Source: Minerbi A, Gonzalez E, Brereton N, Fitzcharles MA, Chevalier S, Shir Y. Altered serum bile acid profile in fibromyalgia is associated with specific gut microbiome changes and symptom severity. Pain. 2022 May 19. doi: 10.1097/j.pain.0000000000002694. Epub ahead of print. PMID: 35587528. https://pubmed.ncbi.nlm.nih.gov/35587528/

Multi-omics provide evidence for an anti-inflammatory immune signature and metabolic alterations in patients with Long COVID Syndrome; an exploratory study

Abstract:

Despite the increasing prevalence of patients with Long Covid Syndrome (LCS), to date the pathophysiology of the disease is still unclear, and therefore diagnosis and therapy are a complex effort without any standardization. To address these issues, we performed a broad exploratory screening study applying state-of-the-art post-genomic profiling methods to blood plasma derived from three groups: 1) healthy individuals vaccinated against SARS-CoV-2 without exposure to the full virus, 2) asymptomatic fully recovered patients at least three months after SARS-CoV-2 infection, 3) symptomatic patients at least 3 months after a SARS-CoV-2 infection, here designated as Long Covid Syndrome (LCS) patients.

Multiplex cytokine profiling indicated slightly elevated cytokine levels in recovered individuals in contrast to LCS patients, who displayed lowest levels of cytokines. Label-free proteome profiling corroborated an anti-inflammatory status in LCS characterized by low acute phase protein levels and a uniform down-regulation of macrophage-derived secreted proteins, a pattern also characteristic for chronic fatigue syndrome (CFS).

Along those lines, eicosanoid and docosanoid analysis revealed high levels of omega-3 fatty acids and a prevalence of anti-inflammatory oxylipins in LCS patients compared to the other study groups. Targeted metabolic profiling indicated low amino acid and triglyceride levels and deregulated acylcarnithines, characteristic for CFS and indicating mitochondrial stress in LCS patients. The anti-inflammatory osmolytes taurine and hypaphorine were significantly up-regulated in LCS patients.

In summary, here we present evidence for a specific anti-inflammatory and highly characteristic metabolic signature in LCS which could serve for future diagnostic purposes and help to establish rational therapeutic interventions in these patients.

Source: Johannes J Kovarik, Andrea Bileck, Gerhard Hagn, Samuel M Meier Menches, Tobias Frey, Anna Kaempf, Marlene Hollenstein, Tarik Shoumariyeh, Lukas Skos, Birgit Reiter, Marlene C Gerner, Andreas Spannbauer, Ena Hasimbegovic, Doreen Schmidl, Gerhard Garhoefer, Mariann Gyoengyoesi, Klaus G Schmetterer, Christopher Gerner. Multi-omics provide evidence for an anti-inflammatory immune signature and metabolic alterations in patients with Long COVID Syndrome; an exploratory study. medRxiv 2022.07.11.22277499; doi: https://doi.org/10.1101/2022.07.11.22277499 (Full study available as PDF file)

Could the kynurenine pathway be the key missing piece of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) complex puzzle?

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex and debilitating disease with a substantial social and economic impact on individuals and their community. Despite its importance and deteriorating impact, progresses in diagnosis and treatment of ME/CFS is limited. This is due to the unclear pathophysiology of the disease and consequently lack of prognostic biomarkers.

To investigate pathophysiology of ME/CFS, several potential pathologic hallmarks have been investigated; however, these studies have failed to report a consistent result. These failures in introducing the underlying reason for ME/CFS have stimulated considering other possible contributing mechanisms such as tryptophan (TRP) metabolism and in particular kynurenine pathway (KP).

KP plays a central role in cellular energy production through the production of nicotinamide adenine dinucleotide (NADH). In addition, this pathway has been shown to mediate immune response and neuroinflammation through its metabolites. This review, we will discuss the pathology and management of ME/CFS and provide evidence pertaining KP abnormalities and symptoms that are classic characteristics of ME/CFS. Targeting the KP regulation may provide innovative approaches to the management of ME/CFS.

Source: Kavyani B, Lidbury BA, Schloeffel R, Fisher PR, Missailidis D, Annesley SJ, Dehhaghi M, Heng B, Guillemin GJ. Could the kynurenine pathway be the key missing piece of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) complex puzzle? Cell Mol Life Sci. 2022 Jul 11;79(8):412. doi: 10.1007/s00018-022-04380-5. PMID: 35821534. https://link.springer.com/article/10.1007/s00018-022-04380-5  (Full text)

No replication of previously reported association with genetic variants in the T cell receptor alpha (TRA) locus for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disease with a variety of symptoms such as post-exertional malaise, fatigue, and pain, but where aetiology and pathogenesis are unknown. An increasing number of studies have implicated the involvement of the immune system in ME/CFS. Furthermore, a hereditary component is suggested by the reported increased risk for disease in relatives, and genetic association studies are being performed to identify potential risk variants.

We recently reported an association with the immunologically important human leucocyte antigen (HLA) genes HLA-C and HLA-DQB1 in ME/CFS. Furthermore, a genome-wide genetic association study in 42 ME/CFS patients reported significant association signals with two variants in the T cell receptor alpha (TRA) locus (P value <5 × 10-8). As the T cell receptors interact with the HLA molecules, we aimed to replicate the previously reported findings in the TRA locus using a large Norwegian ME/CFS cohort (409 cases and 810 controls) and data from the UK biobank (2105 cases and 4786 controls).

We investigated numerous SNPs in the TRA locus, including the two previously ME/CFS-associated variants, rs11157573 and rs17255510. No associations were observed in the Norwegian cohort, and there was no significant association with the two previously reported SNPs in any of the cohorts. However, other SNPs showed signs of association (P value <0.05) in the UK Biobank cohort and meta-analyses of Norwegian and UK biobank cohorts, but none survived correction for multiple testing. Hence, our research did not identify any reliable associations with variants in the TRA locus.

Source: Ueland M, Hajdarevic R, Mella O, Strand EB, Sosa DD, Saugstad OD, Fluge Ø, Lie BA, Viken MK. No replication of previously reported association with genetic variants in the T cell receptor alpha (TRA) locus for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Transl Psychiatry. 2022 Jul 11;12(1):277. doi: 10.1038/s41398-022-02046-1. PMID: 35821115. https://www.nature.com/articles/s41398-022-02046-1 (Full text)

The Facilitation of Clinical and Therapeutic Discoveries in Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome and Related Diseases: A Protocol for the You + ME Registry Research Platform

Abstract:

Background: ME/CFS (Myalgic Encephalomyelitis / Chronic Fatigue Syndrome) is a chronic, complex, heterogeneous disease that affects millions and lacks both diagnostics and treatments. Big data, or the collection of vast quantities of data that can be mined for information, has transformed the understanding of many complex illnesses like cancer and multiple sclerosis, by dissecting heterogeneity, identifying subtypes, and enabling the development of personalized treatments. It is possible that big data can reveal the same for ME/CFS.

Objective: To describe the protocol for the You + ME Registry, present preliminary results related to participant enrollment and satisfaction, and discuss the limitations of the registry as well as next steps.

Methods: Solve M.E. developed and launched the You + ME Registry to collect longitudinal health data from people with ME/CFS, people with Long COVID (LC) and control volunteers using rigorous protocols designed to harmonize with other groups collecting data from similar groups of people.

Results: The Registry now has over 4,200 geographically-diverse participants (3,033 people with ME/CFS, 833 post-COVID, and 473 control volunteers) with an average of 72 new people registered every week. It has qualified as “great” using a Net Promotor Score, indicating registrants are likely to recommend to a friend. Analyses of collected data are currently underway and preliminary findings are expected in the near future.

Conclusions: The Registry is an invaluable resource because it integrates with a symptom tracking app, as well as a biorepository, to provide a robust and rich dataset that is available to qualified researchers. Accordingly, it facilitates collaboration that may ultimately uncover causes and help accelerate the development of therapies.

International registered report: DERR1-10.2196/36798.

Source: Ramiller A, Mudie K, Seibert E, Whittaker S. The Facilitation of Clinical and Therapeutic Discoveries in Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome and Related Diseases: A Protocol for the You + ME Registry Research Platform. JMIR Res Protoc. 2022 Jun 5. doi: 10.2196/36798. Epub ahead of print. PMID: 35816681. https://pubmed.ncbi.nlm.nih.gov/35816681/ https://preprints.jmir.org/preprint/36798/accepted (Full study available as PDF file)

Evidence for active Epstein-Barr virus infection in patients with persistent, unexplained illnesses: elevated anti-early antigen antibodies

Abstract:

Forty-four patients, including 26 adults and 18 children under 15 years of age, were referred for evaluation of recurrent or persistent illnesses, with symptoms including pharyngitis, lymphadenopathy, fever, headaches, arthralgia, fatigue, depression, dyslogia, and myalgia. Thirty-nine patients were positive for Epstein-Barr virus antibody with antibody levels compatible with active infection for at least 1 year. Antiviral capsid antigen and anti-early antigen titers of patients were significantly greater (p less than 0.001) than age-group-matched controls. The frequency, number, duration, and patterns of symptoms, as well as patient sex, were compared by age in study patients seropositive and seronegative for Epstein-Barr virus. Illness patterns were not associated with changes in specific antibody titers or clinical findings. Lymphocyte phenotype and function analyses were done in 11 of the 39 patients positive for Epstein-Barr virus antibody; no consistent differences from normal were found. Only 1 of 32 patients had circulating interferon, in contrast to 7 of 7 patients with acute infectious mononucleosis. There were many adverse consequences of the illness. Epstein-Barr virus infection may not be self-limiting, and the virus may be associated with clinically recognizable illness other than infectious mononucleosis in children as well as in adults.

Source:Jones JF, Ray CG, Minnich LL, Hicks MJ, Kibler R, Lucas DO. Evidence for active Epstein-Barr virus infection in patients with persistent, unexplained illnesses: elevated anti-early antigen antibodies. Ann Intern Med. 1985 Jan;102(1):1-7. doi: 10.7326/0003-4819-102-1-. PMID: 2578266. https://pubmed.ncbi.nlm.nih.gov/2578266/

The epidemiology of post viral fatigue syndrome

Abstract:

The epidemiology of the post viral fatigue syndrome was studied for the years 1985-86. With a strict definition of the syndrome, it was found that there were many misconceptions about this illness. The sex incidence was nearly equal with a similar pattern of twin peaks at 25-29 years and 40-45 years. At diagnosis, 56% were ill for three to six months and only 9% for more than two years. It is estimated that this syndrome is more common than infectious mononucleosis.

Source: Ho-Yen DO. The epidemiology of post viral fatigue syndrome. Scott Med J. 1988 Dec;33(6):368-9. doi: 10.1177/003693308803300607. PMID: 2854300. https://pubmed.ncbi.nlm.nih.gov/2854300/

Post-infectious disease syndrome

Abstract:

Many post-infectious syndromes have been recognized in the last 50 years, some following viral infections and others closely related to bacterial disease. The occurrence of prolonged fatigue following an apparent viral illness of varying severity is also well documented. The lack of a recognizable precipitating cause and the tendency for epidemic fatigue to occur among hospital staff led many to believe that the illness may be psychogenic in origin. However, there is serological evidence that some cases may follow enterovirus infections or occasionally delayed convalescence from infectious mononucleosis. Much interesting work is currently in progress relating fatigue to persisting immunological abnormalities, and the development of molecular immunology makes this a most exciting field of research. This paper reviews the evidence for and against a definitive post-viral fatigue syndrome and examines the results of research carried out in the last 50 years.

Source: Bannister BA. Post-infectious disease syndrome. Postgrad Med J. 1988 Jul;64(753):559-67. doi: 10.1136/pgmj.64.753.559. PMID: 3074289; PMCID: PMC2428896.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2428896/ (Full text)

Ensuring the Voice of the Very Severely Affected Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patient Is Heard in Research—A Research Model

Abstract:

Most of the research about Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) has focused on ambulant patients who are able to attend clinics. It is estimated that 25% of people with ME/CFS are severely, or very severely, affected and are housebound or bedbound; some require tube feeding. Due to the severity of their illness, these patients have largely been excluded from research and are often described as ‘hard to reach.’ A questionnaire was devised to gather data about their experiences of accessing tube feeding. By making the necessary reasonable adjustments, such as direct outreach and the option to complete the questionnaire by telephone or texting, very severely affected patients were enabled to participate and provided invaluable contributions. This study aimed to act as a model for future researchers.
Source: Baxter H. Ensuring the Voice of the Very Severely Affected Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patient Is Heard in Research—A Research Model. Healthcare. 2022; 10(7):1278. https://doi.org/10.3390/healthcare10071278  https://www.mdpi.com/2227-9032/10/7/1278 (Full text)

Long COVID: Association of Functional Autoantibodies against G-Protein-Coupled Receptors with an Impaired Retinal Microcirculation

Abstract:

Long COVID (LC) describes the clinical phenotype of symptoms after infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Diagnostic and therapeutic options are limited, as the pathomechanism of LC is elusive. As the number of acute SARS-CoV-2 infections was and is large, LC will be a challenge for the healthcare system. Previous studies revealed an impaired blood flow, the formation of microclots, and autoimmune mechanisms as potential factors in this complex interplay. Since functionally active autoantibodies against G-protein-coupled receptors (GPCR-AAbs) were observed in patients after SARS-CoV-2 infection, this study aimed to correlate the appearance of GPCR-AAbs with capillary microcirculation.

The seropositivity of GPCR-AAbs was measured by an established cardiomyocyte bioassay in 42 patients with LC and 6 controls. Retinal microcirculation was measured by OCT-angiography and quantified as macula and peripapillary vessel density (VD) by the Erlangen-Angio Tool. A statistical analysis yielded impaired VD in patients with LC compared to the controls, which was accentuated in female persons. A significant decrease in macula and peripapillary VD for AAbs targeting adrenergic β2-receptor, MAS-receptor angiotensin-II-type-1 receptor, and adrenergic α1-receptor were observed. The present study might suggest that a seropositivity of GPCR-AAbs can be linked to an impaired retinal capillary microcirculation, potentially mirroring the systemic microcirculation with consecutive clinical symptoms.

Source: Szewczykowski C, Mardin C, Lucio M, Wallukat G, Hoffmanns J, Schröder T, Raith F, Rogge L, Heltmann F, Moritz M, Beitlich L, Schottenhamml J, Herrmann M, Harrer T, Ganslmayer M, Kruse FE, Kräter M, Guck J, Lämmer R, Zenkel M, Gießl A, Hohberger B. Long COVID: Association of Functional Autoantibodies against G-Protein-Coupled Receptors with an Impaired Retinal Microcirculation. Int J Mol Sci. 2022 Jun 29;23(13):7209. doi: 10.3390/ijms23137209. PMID: 35806214. https://www.mdpi.com/1422-0067/23/13/7209/htm (Full text)