Category: Biomarker

Saliva Fatigue Biomarker Index As a Marker for Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in a Community Based Sample

Abstract:

Objective: The prevalence of pediatric Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) has been estimated from an ethnically and sociodemographically diverse community-based random sample of 10,119 youth aged 5-17. A team of physicians made a final diagnosis of ME/CFS if the participants met criteria for up to three selected case definitions following medical and psychiatric evaluations. We assessed whether a salivary biomarker of fatigue could identify youth with ME/CFS.

Study design: We examined the ratio of the concentrations of 2 peptide fragments in saliva, referred to as the Fatigue Biomarker Index (FBI), in participants from our study diagnosed with ME/CFS (n=59) and matched controls (n=39).

Results: Significant overall differences were found in the FBI between those participants with severe ME/CFS and those with ME/CFS and the controls.

Conclusions: If confirmed in other populations, the FBI could serve as an objective test to aid in the diagnosis of severe ME/CFS.

Source: Jason LA, Kalns J, Richarte A, Katz BZ, Torres C. Saliva Fatigue Biomarker Index As a Marker for Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in a Community Based Sample. Fatigue. 2021;9(4):189-195. doi: 10.1080/21641846.2021.1994222. Epub 2021 Oct 27. PMID: 35186443; PMCID: PMC8855987.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8855987/ (Full text)

The maintained attention assessment in patients affected by Myalgic encephalomyelitis/chronic fatigue syndrome: a reliable biomarker?

Abstract:

The maintained attention is the cause of great functional limitations in CFS/ME, a disease that mainly affects women in the central period of life. Cognitive function is explored using the Montreal Cognitive Assessment, the maintained attention using the Toulouse-Piéron test with which the Global Index of Attention and Perception (GIAP) is obtained, the fatigue using the visual analog scale and the perception of effort using the modified Borg scale. The final sample were 84 patients (66 women/18 men) who met diagnostic criteria (Fukuda-1994, Carruthers-2011) and 22 healthy controls (14 women/8 men).

Most of patients maintain normal cognitive function, showing low or very low attention score in the 70% of patients with a marked cognitive fatigue compared to the control group (p < 0.05). There were no significant differences between genders in GIAP or fatigue for CFS/ME; however, sick women perceive cognitive effort higher than men.

Deficits in sustained attention and the perception of fatigue, so effort after performing the proposed test are a sensitive and reliable indicator that allows us to substantiate a clinical suspicion and refer patients for further studies in order to confirm or rule out CFS/ME.

Source: Murga I, Aranburu L, Gargiulo PA, Gómez-Esteban JC, Lafuente JV. The maintained attention assessment in patients affected by Myalgic encephalomyelitis/chronic fatigue syndrome: a reliable biomarker? J Transl Med. 2021 Dec 4;19(1):494. doi: 10.1186/s12967-021-03153-1. PMID: 34863209. https://pubmed.ncbi.nlm.nih.gov/34863209/

Multi-omics of host-microbiome interactions in short- and long-term Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex, multi-system, debilitating disability manifesting as severe fatigue and post-exertional malaise. The chronic dysfunctions in ME/CFS are increasingly recognized as significant health factors with potential parallels with “long COVID”. However, the etiology of ME/CFS remains elusive with limited high-resolution human studies. In addition, reliable biomarker-based diagnostics have not been well-established, but may assist in disease classification, particularly during different temporal phases of the disease. Here, we performed deep multi-omics (shotgun metagenomics of gut microbiota and plasma metabolomics) and clinical phenotyping of healthy controls (n=79) vs. two cohorts of ME/CFS patients: those with short-term disease (<4 years, n=75), and patients with long-term disease (>10y, n=79).

Overall, ME/CFS was characterized by reduced gut microbiome diversity and richness with high heterogeneity, and depletion of sphingomyelins and short-chain fatty acids in the plasma. We found significant differences when stratifying by cohort; short-term ME/CFS was associated with more microbial dysbiosis, but long-term ME/CFS was associated with markedly more severe phenotypic and metabolic abnormalities. We identified a reduction in the gene-coding capacity (and relative abundance of butyrate producers) of microbial butyrate biosynthesis together with a reduction in the plasma concentration of butyrate, especially in the short-term group. Global co-association and detailed gene pathway correlation analyses linking the microbiome and metabolome identified additional potential biological mechanisms underlying host-microbiome interactions in ME/CFS, including bile acids and benzoate pathways.

Finally, we built multiple state-of-the-art classifiers to identify microbes, microbial gene pathways, metabolites, and clinical features that individually or together, were most able to differentiate short or long-term MECFS, or MECFS vs. healthy controls. Taken together, our study presents the highest resolution, multi-cohort and multi-omics analysis to date, providing an important resource to facilitate mechanistic hypotheses of host-microbiome interactions in ME/CFS.

Source: Ruoyun Xiong, Courtney Gunter, Elizabeth Fleming, Suzanne Vernon, Lucinda Bateman, Derya Unutmaz, Julia Oh. Multi-omics of host-microbiome interactions in short- and long-term Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). bioRxiv 2021.10.27.466150; doi: https://doi.org/10.1101/2021.10.27.466150 https://www.biorxiv.org/content/10.1101/2021.10.27.466150v1 (Full study available for download)

Induced pluripotent stem cells as suitable sensors for fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Background: Fibromyalgia (FM) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are devastating metabolic neuroimmune diseases that are difficult to diagnose because of the presence of numerous symptoms and a lack of specific biomarkers. Despite patient heterogeneity linked to patient subgroups and variation in disease severity, anomalies are found in the blood and plasma of these patients when compared with healthy control groups. The seeming specificity of these “plasma factors”, as recently reported by Ron Davis and his group at Stanford University, CA, United States, and observations by our group, have led to the proposal that induced pluripotent stem cells (iPSCs) may be used as metabolic sensors for FM and ME/CFS, a hypothesis that is the basis for this in-depth review.

Aim: To identify metabolic signatures in FM and/or ME/CFS supporting the existence of disease-associated plasma factors to be sensed by iPSCs.

Methods: A PRISMA (Preferred Reported Items for Systematic Reviews and Meta-analysis)-based systematic review of the literature was used to select original studies evaluating the metabolite profiles of FM and ME/CFS body fluids. The MeSH terms “metabolomic” or “metabolites” in combination with FM and ME/CFS disease terms were screened against the PubMed database. Only original studies applying omics technologies, published in English, were included. The data obtained were tabulated according to the disease and type of body fluid analyzed. Coincidences across studies were searched and P-values reported by the original studies were gathered to document significant differences found in the disease groups.

Results: Eighteen previous studies show that some metabolites are commonly altered in ME/CFS and FM body fluids. In vitro cell-based assays have the potential to be developed as screening platforms, providing evidence for the existence of factors in patient body fluids capable of altering morphology, differentiation state and/or growth patterns. Moreover, they can be further developed using approaches aimed at blocking or reversing the effects of specific plasma/serum factors seen in patients. The documented high sensitivity and effective responses of iPSCs to environmental cues suggests that these pluripotent cells could form robust, reproducible reporter systems of metabolic diseases, including ME/CFS and FM. Furthermore, culturing iPSCs, or their mesenchymal stem cell counterparts, in patient-conditioned medium may provide valuable information to predict individual outcomes to stem-cell therapy in the context of precision medicine studies.

Conclusion: This opinion review explains our hypothesis that iPSCs could be developed as a screening platform to provide evidence of a metabolic imbalance in FM and ME/CFS.

Source: Monzón-Nomdedeu MB, Morten KJ, Oltra E. Induced pluripotent stem cells as suitable sensors for fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome. World J Stem Cells. 2021 Aug 26;13(8):1134-1150. doi: 10.4252/wjsc.v13.i8.1134. PMID: 34567431; PMCID: PMC8422931. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8422931/ (Full article)

Potential of Activin B as a Clinical Biomarker in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

Reliable serum biomarkers are of immense need for diagnostic purposes of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)-a disabling and complex disease for which diagnosis is mainly based on clinical symptoms. The aim of this study was to evaluate a possible diagnostic potential of activin B by directly comparing 134 cases of ME/CFS with 54 healthy controls.

Analyses of human activin B level in plasma samples were performed using a validated human activin B ELISA assay. The results of the study show that activin B levels did not differ statistically significantly between ME/CFS patients and healthy controls (p = 0.6511). No gender or age-related differences in activin B levels were observed in the ME/CFS group and healthy controls. The level of activin B tended to decrease with increasing visual analogue scale score (r = -0.2004; p = 0.5085) nevertheless the results obtained so far does not support the clinical utility of activin B as a biomarker for ME/CFS.

Source: Gravelsina S, Nora-Krukle Z, Vilmane A, Svirskis S, Vecvagare K, Krumina A, Murovska M. Potential of Activin B as a Clinical Biomarker in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Biomolecules. 2021 Aug 11;11(8):1189. doi: 10.3390/biom11081189. PMID: 34439855. https://pubmed.ncbi.nlm.nih.gov/34439855/

Chronic fatigue syndrome and epigenetics: The case for hyperbaric oxygen therapy in biomarker identification

Abstract:

Chronic fatigue syndrome (CFS) is a poorly-understood respiratory condition that affects millions of individuals. Hyperbaric oxygen therapy (HBOT) is a treatment option being considered to address CFS as it is suggested to combat fatigue and increase oxygenation. HBOT provides two opportunities in advancing research of CFS: it may provide data on symptom amelioration and be utilized in the search for a biomarker. By either identifying biomarkers before using HBOT to compare epigenomes of patients before and after treatment or using HBOT to find epigenetic discrepancies between patients with and without treatment, matching epigenetic regulation with symptom amelioration may significantly advance the understanding of the etiology and treatment mechanism for CFS. EPAS1/HIF-2α is a leading candidate for an epigenetic biomarker as it responds differentially to hypoxic and normoxic conditions, which degrades more slowly in hypoxic conditions. Epigenetic regulation of EPAS1/HIF-2α in such differential conditions may be explored in HBOT experiments. In addition to HBOT as a promising treatment option for CFS symptoms, it may aid the identification of biomarkers in CFS. Further research into both outcomes is strongly encouraged.

Source: Shah RJ. Chronic fatigue syndrome and epigenetics: The case for hyperbaric oxygen therapy in biomarker identification. J Pulmonol Respir Res. 2021; 5: 027-030. DOI: 10.29328/journal.jprr.1001020 https://www.heighpubs.org/jprr/jprr-aid1020.php (Full text)

Altered endothelial dysfunction-related miRs in plasma from ME/CFS patients

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disease characterized by unexplained debilitating fatigue. Although the etiology is unknown, evidence supports immunological abnormalities, such as persistent inflammation and immune-cell activation, in a subset of patients. Since the interplay between inflammation and vascular alterations is well-established in other diseases, endothelial dysfunction has emerged as another player in ME/CFS pathogenesis.

Endothelial nitric oxide synthase (eNOS) generates nitric oxide (NO) that maintains endothelial homeostasis. eNOS is activated by silent information regulator 1 (Sirt1), an anti-inflammatory protein. Despite its relevance, no study has addressed the Sirt1/eNOS axis in ME/CFS. The interest in circulating microRNAs (miRs) as potential biomarkers in ME/CFS has increased in recent years. Accordingly, we analyze a set of miRs reported to modulate the Sirt1/eNOS axis using plasma from ME/CFS patients.

Our results show that miR-21, miR-34a, miR-92a, miR-126, and miR-200c are jointly increased in ME/CFS patients compared to healthy controls. A similar finding was obtained when analyzing public miR data on peripheral blood mononuclear cells. Bioinformatics analysis shows that endothelial function-related signaling pathways are associated with these miRs, including oxidative stress and oxygen regulation. Interestingly, histone deacetylase 1, a protein responsible for epigenetic regulations, represented the most relevant node within the network.

In conclusion, our study provides a basis to find endothelial dysfunction-related biomarkers and explore novel targets in ME/CFS.

Source: Blauensteiner J, Bertinat R, León LE, Riederer M, Sepúlveda N, Westermeier F. Altered endothelial dysfunction-related miRs in plasma from ME/CFS patients. Sci Rep. 2021 May 19;11(1):10604. doi: 10.1038/s41598-021-89834-9. PMID: 34011981. https://pubmed.ncbi.nlm.nih.gov/34011981/

Insights into Metabolite Diagnostic Biomarkers for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a persistent and unexplained pathological state characterized by exertional and severely debilitating fatigue, with/without infectious or neuropsychiatric symptoms, and with a minimum duration of 6 consecutive months. Its pathogenesis is not fully understood. There are no firmly established diagnostic biomarkers or treatment, due to incomplete understanding of the etiology of ME/CFS and diagnostic uncertainty. Establishing a biomarker for the objective diagnosis is urgently needed to treat a lot of patients. Recently, research on ME/CFS using metabolome analysis methods has been increasing. Here, we overview recent findings concerning the metabolic features in patients with ME/CFS and the animal models which contribute to the development of diagnostic biomarkers for ME/CFS and its treatment. In addition, we discuss future perspectives of studies on ME/CFS.

Source: Yamano E, Watanabe Y, Kataoka Y. Insights into Metabolite Diagnostic Biomarkers for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Int J Mol Sci. 2021 Mar 26;22(7):3423. doi: 10.3390/ijms22073423. PMID: 33810365. https://pubmed.ncbi.nlm.nih.gov/33810365/

Recursive ensemble feature selection provides a robust mRNA expression signature for myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disorder characterized by disabling fatigue. Several studies have sought to identify diagnostic biomarkers, with varying results. Here, we innovate this process by combining both mRNA expression and DNA methylation data. We performed recursive ensemble feature selection (REFS) on publicly available mRNA expression data in peripheral blood mononuclear cells (PBMCs) of 93 ME/CFS patients and 25 healthy controls, and found a signature of 23 genes capable of distinguishing cases and controls.

REFS highly outperformed other methods, with an AUC of 0.92. We validated the results on a different platform (AUC of 0.95) and in DNA methylation data obtained from four public studies on ME/CFS (99 patients and 50 controls), identifying 48 gene-associated CpGs that predicted disease status as well (AUC of 0.97). Finally, ten of the 23 genes could be interpreted in the context of the derailed immune system of ME/CFS.

Source: Metselaar, P.I., Mendoza-Maldonado, L., Li Yim, A.Y.F. et al. Recursive ensemble feature selection provides a robust mRNA expression signature for myalgic encephalomyelitis/chronic fatigue syndrome. Sci Rep 11, 4541 (2021). https://doi.org/10.1038/s41598-021-83660-9 https://www.nature.com/articles/s41598-021-83660-9 (Full text)

Are Circulating FGF21 and NT-proBNP promising novel biomarkers in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome?

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a chronic, disabling, and complex multisystem illness of unknown etiology. The protein FGF21 regulates glucose homeostasis and lipid metabolism, and the protein NT-proBNP is strongly associated with an elevated cardiovascular risk; however, little is known about their role in ME/CFS patients. To address this gap, we explored the association between FGF21 and NT-proBNP and oxidative stress and inflammatory markers in ME/CFS.

Twenty-one ME/CFS patients and 20 matched healthy controls were included in the study. Participants filled out validated self-reported questionnaires on their current health status covering demographic and clinical characteristics. Plasma showed significantly decreased total antioxidant capacity and increased lipoperoxides levels (p = 0.009 and p = 0.021, respectively) in ME/CFS. These ME/CFS patients also had significantly increased levels of inflammatory cytokines (IL-1β, IL-6, IL-10, TNF-α, and C-reactive protein (p < 0.05 for all) but not for IL-8 (p = 0.833) in ME/CFS, indicating low-grade systemic inflammation status. Circulating FGF21 and NT-proBNP levels were significantly higher (p < 0.0001 and p = 0.005, respectively) in ME/CFS patients than in healthy controls.

Significantly positive correlations were found between NT-proBNP levels and IL-1β and IL-6 (p = 0.04 and p = 0.01) in ME/CFS patients but not between FGF21 and these cytokines. In contrast, no significant correlations were found for either FGF21 or NT-proBNP in controls. These findings lead to the hypothesis that elevated FGF21 and NT-proBNP levels and the association between NT-proBNP and inflammation may be promising novel diagnostic and therapeutic targets in ME/CFS.

Source: Domingo JC, Cordobilla B, Ferrer R, Giralt M, Alegre-Martin J, Castro-Marrero J. Are Circulating FGF21 and NT-proBNP promising novel biomarkers in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome? Antioxid Redox Signal. 2020 Dec 22. doi: 10.1089/ars.2020.8230. Epub ahead of print. PMID: 33353469. https://pubmed.ncbi.nlm.nih.gov/33353469/