Exploring the role of galectin-9 and artemin as biomarkers in long COVID with chronic fatigue syndrome: links to inflammation and cognitive function

Abstract:

This study aimed to assess plasma galectin-9 (Gal-9) and artemin (ARTN) concentrations as potential biomarkers to differentiate individuals with Long COVID (LC) patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) from SARS-CoV-2 recovered (R) and healthy controls (HCs).

Receiver operating characteristic (ROC) curve analysis determined a cut-off value of plasma Gal-9 and ARTN to differentiate LC patients from the R group and HCs in two independent cohorts.

Positive correlations were observed between elevated plasma Gal-9 levels and inflammatory markers (e.g. SAA and IP-10), as well as sCD14 and I-FABP in LC patients. Gal-9 also exhibited a positive correlation with cognitive failure scores, suggesting its potential role in cognitive impairment in LC patients with ME/CFS.

This study highlights plasma Gal-9 and/or ARTN as sensitive screening biomarkers for discriminating LC patients from controls. Notably, the elevation of LPS-binding protein in LC patients, as has been observed in HIV infected individuals, suggests microbial translocation. However, despite elevated Gal-9, we found a significant decline in ARTN levels in the plasma of people living with HIV (PLWH). Our study provides a novel and important role for Gal-9/ARTN in LC pathogenesis.

Source: Elahi Shokrollah , Rezaeifar Maryam , Osman Mohammed , Shahbaz Shima. Exploring the role of galectin-9 and artemin as biomarkers in long COVID with chronic fatigue syndrome: links to inflammation and cognitive function. Frontiers in Immunology, Vol 15, 2024. DOI=10.3389/fimmu.2024.1443363. ISSN=1664-3224. https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1443363 (Full text)

 

Over-Representation of Torque Teno Mini Virus 9 in a Subgroup of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Study

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disorder classified by the WHO as postviral fatigue syndrome (ICD-11 8E49 code). Diagnosing ME/CFS, often overlapping with fibromyalgia (FM), is challenging due to nonspecific symptoms and lack of biomarkers. The etiology of ME/CFS and FM is poorly understood, but evidence suggests viral infections play a critical role. This study employs microarray technology to quantitate viral RNA levels in immune cells from ME/CFS, FM, or co-diagnosed cases, and healthy controls.

The results show significant overexpression of the Torque Teno Mini Virus 9 (TTMV9) in a subgroup of ME/CFS patients which correlate with abnormal HERV and immunological profiles. Increased levels of TTMV9 transcripts accurately discriminate this subgroup of ME/CFS patients from the other study groups, showcasing its potential as biomarker for patient stratification and the need for further research into its role in the disease. Validation of the findings seems granted in extended cohorts by continuation studies.

Source: Giménez-Orenga K, Martín-Martínez E, Oltra E. Over-Representation of Torque Teno Mini Virus 9 in a Subgroup of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Study. Pathogens. 2024 Sep 1;13(9):751. doi: 10.3390/pathogens13090751. PMID: 39338942; PMCID: PMC11435283. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11435283/ (Full text)

The persistence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) after SARS-CoV-2 infection: A systematic review and meta-analysis

Highlights:

  • SARS-CoV-2 can trigger Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.
  • 51% of Long COVID-19 patients have Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.
  • Long COVID-19 is a new name for an old disease.

Abstract:

Objectives: Long COVID-19 (LC) patients experience a number of chronic idiopathic symptoms that are highly similar to those of post-viral Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). We have therefore performed a systematic review and meta-analysis to determine the proportion of LC patients that satisfy ME/CFS diagnostic criteria.

Methods: Clinical studies published between January 2020 to May 2023 were identified using the PubMed, Web of Science, Embase and CINAHL databases. Publication inclusion/exclusion criteria were formulated using the global CoCoPop framework. Data were pooled using a random-effects model with a restricted maximum-likelihood estimator. Study quality was assessed using the Joanna Briggs Institute critical assessment tool.

Results: We identified 13 eligible studies that reported a total of 1,973 LC patients. Our meta-analysis indicated that 51% (95% CI, 42%-60%) of LC patients satisfied ME/CFS diagnostic criteria with fatigue, sleep disruption, and muscle/joint pain being the most common symptoms. Importantly, LC patients also experienced the ME/CFS hallmark symptom, post-exertional malaise.

Conclusions: Our study not only demonstrates that LC patients exhibit similar symptom clusters to ME/CFS, but that approximately half of LC patients satisfy a diagnosis of ME/CFS. Our findings suggest that current ME/CFS criteria could be adapted to the identification of a subset of LC patients that may facilitate the standardized diagnosis, management and the recruitment for clinical studies in the future.

Source: Ankush Dehlia, Mark A. Guthridge. The persistence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) after SARS-CoV-2 infection: A systematic review and meta-analysis. Journal of Infection, 2024, 106297, ISSN 0163-4453, https://doi.org/10.1016/j.jinf.2024.106297.
https://www.sciencedirect.com/science/article/pii/S0163445324002317 (Full text)

A Network Medicine Approach to Investigating ME/CFS Pathogenesis in Severely Ill Patients: A Pilot Study

Abstract:

This pilot study harnessed the power of network medicine to unravel the complex pathogenesis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). By utilizing a network analysis on whole genome sequencing (WGS) data from the Severely Ill Patient Study (SIPS), we identified ME/CFS-associated proteins and delineated the corresponding network-level module, termed the SIPS disease module, together with its relevant pathways. This module demonstrated significant overlap with genes implicated in fatigue, cognitive disorders, and neurodegenerative diseases.

Our pathway analysis revealed potential associations between ME/CFS and conditions such as COVID-19, Epstein-Barr virus (EBV) infection, neurodegenerative diseases, and pathways involved in cortisol synthesis and secretion, supporting the hypothesis that ME/CFS is a neuroimmune disorder. Additionally, our findings underscore a potential link between ME/CFS and estrogen signaling pathways, which may elucidate the higher prevalence of ME/CFS in females.

These findings provide insights into the pathogenesis of ME/CFS from a network medicine perspective and highlight potential therapeutic targets. Further research is needed to validate these findings and explore their implications for improving diagnosis and treatment.

Source: Li-Yuan Hung, Chan-Shuo Wu, Chia-Jung Chang, Peng Li, Kimberly Hicks, Becky Taurog, Joshua J Dibble, Braxton Morrison, Chimere L Smith, Ronald W Davis, Wenzhong Xiao. A Network Medicine Approach to Investigating ME/CFS Pathogenesis in Severely Ill Patients: A Pilot Study.
medRxiv 2024.09.26.24314417; doi: https://doi.org/10.1101/2024.09.26.24314417 https://www.medrxiv.org/content/10.1101/2024.09.26.24314417v1 (Full text available as PDF file)

Adrenergic dysfunction in patients with myalgic encephalomyelitis/chronic fatigue syndrome and fibromyalgia: A systematic review and meta-analysis

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and fibromyalgia (FM) are comorbid disorders with overlapping symptoms. Research highlights autonomic dysfunction compared to healthy individuals, particularly involving the sympathetic branch. While past reviews focused on neurophysiological assessments, this systematic review summarises biological adrenergic markers, offering deeper insights into the observed sympathetic dysfunction in ME/CFS and FM aiming to identify targetable pathophysiological mechanisms.

Methods: A systematic search was performed on PubMed, Web of Science, Embase and Scopus. Studies investigating peripheral biological markers of adrenergic function in patients with ME/CFS or FM compared to healthy controls at baseline were included. Meta-analyses were performed using R statistical software.

Results: This meta-analysis of 37 studies, encompassing 543 ME/CFS patients and 651 FM patients, compared with 747 and 447 healthy controls, respectively, revealed elevated adrenaline (SMD = .49 [.31-.67]; Z = 5.29, p < .01) and β1 adrenergic receptor expression (SMD = .79 [.06-1.52]; Z = 2.13; p = .03) in blood of ME/CFS patients at rest. Additionally, patients with ME/CFS had a greater increase in the expression of α2A adrenergic receptor (AR, SMD = .57 [.18-.97]; Z = 2.85, p < .01), β2 AR (SMD = .41 [.02-.81]; Z = 2.04; p = .04) and COMT (SMD = .42 [.03-.81]; Z = 2.11; p = .03) after exercise and an increased response of noradrenaline to an orthostatic test (SMD = .11 [-.47 to -.70]; Z = 2.10; p = .04), both found in blood. FM patients showed no significant differences at baseline but exhibited a diminished adrenaline response to exercise (SMD = -.79 [-1.27 to -.30]; Z = -3.14; p < .01).

Conclusion: This systematic review and meta-analysis revealed adrenergic dysfunction mainly in patients with ME/CFS. Higher baseline adrenaline levels and atypical responses to exercise in ME/CFS indicate that sympathetic dysfunction, underscored by adrenergic abnormalities, is more involved in the pathophysiology of ME/CFS rather than FM.

Source: Hendrix J, Fanning L, Wyns A, Ahmed I, Patil MS, Richter E, Van Campenhout J, Ickmans K, Mertens R, Nijs J, Godderis L, Polli A. Adrenergic dysfunction in patients with myalgic encephalomyelitis/chronic fatigue syndrome and fibromyalgia: A systematic review and meta-analysis. Eur J Clin Invest. 2024 Sep 25:e14318. doi: 10.1111/eci.14318. Epub ahead of print. PMID: 39319943. https://pubmed.ncbi.nlm.nih.gov/39319943/

Inhibition of HIF-2α Pathway as a Potential Therapeutic Strategy for Endothelial Dysfunction in Post-COVID Syndrome

Abstract:

Background SARS-CoV-2 infection may lead to Post-COVID Syndrome (PCS), characterized by debilitating symptoms like persistent fatigue, cardiovascular symptoms, and cognitive dysfunction. Persistent endothelial dysfunction (ED) is a potential driver of ongoing symptoms. Yet, the underlying biological mechanisms remain unclear.

Methods In this prospective observational study, we characterized 41 PCS patients and 24 healthy controls (HC, matched out of n = 204, recruited before the pandemic) and investigated the effect of SARS-CoV-2 Spike protein 1 (S1) and plasma from PCS patients on human retinal endothelial cells (HREC).

Results Plasma samples from PCS patients exhibited significantly elevated erythropoietin, VEGF and MCP-1 alongside decreased IL-6 levels compared to HC. Low Haemoglobin and Haematocrit were negatively associated with PCS severity. VEGF levels were positively correlated with Anti-S1 IgG levels in patients and upregulated on mRNA level in HREC exposed to S1. Additionally, S1 exposure promoted ROS production and transiently activated HIF-1α in HREC. Persistent activation of HIF-2α by S1 led to disrupted endothelial integrity. HREC exposed to plasma from severely affected PCS patients showed increased ROS and compromised barrier function. Treatment with Belzutifan, a HIF-2α inhibitor, restored barrier integrity in HREC exposed to S1 or PCS-plasma.

Conclusion These findings suggest that HIF-2α-mediated ED in PCS might be a potential therapeutical target for Belzutifan.

Trial registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT05635552

What Is Known?

  • Endothelial dysfunction (ED) is a consequence of acute SARS-CoV-2 infection and may lead to Post-COVID syndrome (PCS) symptoms.

  • Patients with PCS show elevated inflammation and endothelial dysfunction markers.

  • Spike proteins can persist for up to 12 months post-infection, driving ongoing inflammation and immune activation.

What New Information Does This Article Contribute?

  • Low haemoglobin (Hb) and high VEGF correlate with higher Anti-S1 IgG and low Hb is associated with higher C19-YRS severity score.

  • PCS patients exhibit higher Erythropoietin (EPO) levels when compared to HC.

  • Spike protein 1 (S1) alone and PCS patient’s plasma induce endothelial dysfunction primarily through HIF-2α activation.

  • Both S1 and PCS plasma cause oxidative stress and disrupting endothelial integrity.

  • Inhibition of HIF-2α effectively restores endothelial barrier integrity disrupted by S1 and PCS plasma.

What New Information Does This Article Contribute? Persistent circulation of spike proteins can sustain chronic inflammation and immune activation in patients with PCS. Here we show that plasma from PCS patients exhibits significantly elevated levels of VEGF which positively correlates with Anti-S1 IgG. Low haemoglobin was associated with higher Anti-S1 IgG titres and correlated with a higher C19-YRS severity score. Levels of EPO were higher in PCS patients, with a more pronounced effect observed in patients with cardiovascular symptoms. In human retinal endothelial cells, both S1 and plasma from PCS patients primarily induce ED through HIF-2α activation, rather than NF-κB. Both factors lead to significant oxidative stress, evidenced by increased ROS production which in turn disrupts endothelial barrier integrity and function. Notably, Belzutifan, a HIF-2α inhibitor, can restore this compromised endothelial function, offering a potential therapeutic target for PCS.

Source: Andrea Ribeiro, Timon Kuchler, Maciej Lech, Javier Carbajo-Lozoya, Kristina Adorjan, Hans Christian Stubbe, Martina Seifert, Anna Wöhnle, Veronika Kesseler, Johanna Negele, Uwe Heemann, Christoph Schmaderer. Inhibition of HIF-2α Pathway as a Potential Therapeutic Strategy for Endothelial Dysfunction in Post-COVID Syndrome medRxiv 2024.09.10.24313403; doi: https://doi.org/10.1101/2024.09.10.24313403 https://www.medrxiv.org/content/10.1101/2024.09.10.24313403v1.full-text (Full text)

Untargeted Metabolomics and Quantitative Analysis of Tryptophan Metabolites in Myalgic Encephalomyelitis Patients and Healthy Volunteers: A Comparative Study Using High-Resolution Mass Spectrometry

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic, complex illness characterized by severe and often disabling physical and mental fatigue. So far, scientists have not been able to fully pinpoint the biological cause of the illness and yet it affects millions of people worldwide.

To gain a better understanding of ME/CFS, we compared the metabolic networks in the plasma of 38 ME/CFS patients to those of 24 healthy control participants. This involved an untargeted metabolomics approach in addition to the measurement of targeted substances including tryptophan and its metabolites, as well as tyrosine, phenylalanine, B vitamins, and hypoxanthine using liquid chromatography coupled to mass spectrometry.

mass

Source: Abujrais S, Vallianatou T, Bergquist J. Untargeted Metabolomics and Quantitative Analysis of Tryptophan Metabolites in Myalgic Encephalomyelitis Patients and Healthy Volunteers: A Comparative Study Using High-Resolution Mass Spectrometry. ACS Chem Neurosci. 2024 Sep 20. doi: 10.1021/acschemneuro.4c00444. Epub ahead of print. PMID: 39302151. https://pubs.acs.org/doi/10.1021/acschemneuro.4c00444 (Full text)

Long COVID and hypermobility spectrum disorders have shared pathophysiology

Abstract:

Hypermobility spectrum disorders (HSD) and hypermobile Ehlers-Danlos syndrome (hEDS) are the most common joint hypermobility conditions encountered by physicians, with hypermobile and classical EDS accounting for >90% of all cases. Hypermobility has been detected in up to 30-57% of patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), fibromyalgia, postural orthostatic tachycardia syndrome (POTS), and long COVID (LC) compared to the general population.

Extrapulmonary symptoms, including musculoskeletal pain, dysautonomia disorders, cognitive disorders, and fatigue, are seen in both LC and HSD. Additionally, ME/CFS has overlapping symptoms with those seen in HSD. Mast cell activation and degranulation occurring in both LC and ME/CFS may result in hyperinflammation and damage to connective tissue in these patients, thereby inducing hypermobility.

Persistent inflammation may result in the development or worsening of HSD. Hence, screening for hypermobility and other related conditions including fibromyalgia, POTS, ME/CFS, chronic pain conditions, joint pain, and myalgia is essential for individuals experiencing LC. Pharmacological treatments should be symptom-focused and geared to a patient’s presentation. Paced exercise, massage, yoga, and meditation may also provide benefits.

Source: Ganesh R, Munipalli B. Long COVID and hypermobility spectrum disorders have shared pathophysiology. Front Neurol. 2024 Sep 5;15:1455498. doi: 10.3389/fneur.2024.1455498. PMID: 39301475; PMCID: PMC11410636. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11410636/ (Full text)

Impact of COVID-19 on myalgic encephalomyelitis/chronic fatigue syndrome-like illness prevalence: A cross-sectional survey

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) can be triggered by infectious agents including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the impact of the coronavirus disease 2019 (COVID-19) pandemic on ME/CFS prevalence is not well characterized.

Methods: In this population-based cross-sectional study, we enrolled a stratified random sample of 9,825 adult participants in the Kaiser Permanente Northern California (KPNC) integrated health system from July to October 2022 to assess overall ME/CFS-like illness prevalence and the proportion that were identified following COVID-19 illness. We used medical record and survey data to estimate the prevalence of ME/CFS-like illness based on self-reported symptoms congruent with the 2015 Institute of Medicine ME/CFS criteria. History of COVID-19 was based on a positive SARS-CoV-2 nucleic acid amplification test or ICD-10 diagnosis code in the medical record, or self-report of prior COVID-19 on a survey.

Results: Of 2,745,374 adults in the eligible population, an estimated 45,892 (95% confidence interval [CI]: 32,869, 58,914) or 1.67% (CI 1.20%, 2.15%) had ME/CFS-like illness. Among those with ME/CFS-like illness, an estimated 14.12% (CI 3.64%, 24.6%) developed the illness after COVID-19. Among persons who had COVID-19, those with ME/CFS-like illness after COVID-19 were more likely to be unvaccinated and to have had COVID-19 before June 1, 2021. All persons with ME/CFS-like illness had significant impairment in physical, mental, emotional, social, and occupational functioning compared to persons without ME/CFS-like illness.

Conclusions: In a large, integrated health system, 1.67% of adults had ME/CFS-like illness and 14.12% of all persons with ME/CFS-like illness developed it after COVID-19. Though COVID-19 did not substantially increase ME/CFS-like illness in the KPNC population during the study time period, ME/CFS-like illness nevertheless affects a notable portion of this population and is consistent with estimates of ME/CFS prevalence in other populations. Additional attention is needed to improve awareness, diagnosis, and treatment of ME/CFS.

Source: Wood MS, Halmer N, Bertolli J, Amsden LB, Nugent JR, Lin JS, Rothrock G, Nadle J, Chai SJ, Cope JR, Champsi JH, Yang J, Unger ER, Skarbinski J; for STOP-ME/CFS and COVID-SELECT. Impact of COVID-19 on myalgic encephalomyelitis/chronic fatigue syndrome-like illness prevalence: A cross-sectional survey. PLoS One. 2024 Sep 18;19(9):e0309810. doi: 10.1371/journal.pone.0309810. PMID: 39292671; PMCID: PMC11410243. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11410243/ (Full text)

Virtual reality education on myalgic encephalomyelitis for medical students and healthcare professionals: a pilot study

Abstract:

Introduction: Myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) is a chronic condition which may be characterised by debilitating fatigue, post-exertional malaise, unrefreshing sleep, and cognitive difficulties. ME/CFS has significant negative impact on quality of life for those living with the condition. This may be exacerbated by a lack of knowledge within healthcare regarding the condition. Previous research has found that immersive virtual reality (VR) educational experiences within healthcare education can increase knowledge and empathy.

Methods: The present study employed a quasi-experimental pre-test-post-test design to investigate the impact of a short immersive VR educational experience on knowledge of ME/CFS and empathy for those living with the condition. The VR experience placed participants into a virtual scene which told real life stories of the experience of people living with ME/CFS and their families. 43 participants completed in this pilot study: 28 medical students and 15 primary care health professionals. Participants completed measures of knowledge of ME/CFS and empathy before and after engagement with the experience.

Results: A statistically significant increase was found for levels of knowledge (p < .001, d = 0.74) and empathy (p < .001, d = 1.56) from pre-VR experience levels to post-VR experience levels with a medium and large effect size, respectively. Further analysis revealed no statistically significant difference between baseline levels of knowledge of ME/CFS between healthcare professionals and medical students.

Discussion: The present study is the first to explore the use of this short immersive VR experience as an education tool within healthcare to increase knowledge of ME/CFS, and empathy for those living with the condition. Findings allude to the previously established lack of knowledge of ME/CFS within healthcare although promisingly the increases in knowledge and empathy found suggest that this immersive VR experience has potential to address this. Such changes found in this small-scale pilot study suggest that future research into the use of VR as an educational tool within this setting may be beneficial. Use of a control group, and larger sample size as well as investigation of retention of these changes may also enhance future research.

Source: Anderson T, Duffy G, Corry D. Virtual reality education on myalgic encephalomyelitis for medical students and healthcare professionals: a pilot study. BMC Med Educ. 2024 Sep 17;24(1):1018. doi: 10.1186/s12909-024-05990-2. PMID: 39289650; PMCID: PMC11409778. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11409778/ (Full text)