Tag: proinflammatory cytokines

Inflammation plays a causal role in fatigue-like behavior induced by pelvic irradiation in mice

Abstract:

Fatigue is a persistent and debilitating symptom following radiation therapy for prostate cancer. However, it is not well-understood how radiation targeted to a small region of the body can lead to broad changes in behavior. In this study, we used targeted pelvic irradiation of healthy male mice to test whether inflammatory signaling mediates changes in voluntary physical activity levels.

First, we tested the relationship between radiation dose, blood cell counts, and fatigue-like behavior measured as voluntary wheel-running activity. Next, we used oral minocycline treatments to reduce inflammation and found that minocycline reduces, but does not eliminate, the fatigue-like behavioral changes induced by radiation. We also used a strain of mice lacking the MyD88 adaptor protein and found that these mice also showed less fatigue-like behavior than the wild-type controls. Finally, using serum and brain tissue samples, we determined changes in inflammatory signaling induced by irradiation in wild-type, minocycline treated, and MyD88 knockout mice.

We found that irradiation increased serum levels of IL-6, a change that was partially reversed in mice treated with minocycline or lacking MyD88. Overall, our results suggest that inflammation plays a causal role in radiation-induced fatigue and that IL-6 may be an important mediator.

Source: Wolff BS, Alshawi SA, Feng LR, Juneau PL, Saligan LN. Inflammation plays a causal role in fatigue-like behavior induced by pelvic irradiation in mice. Brain Behav Immun Health. 2021 May 19;15:100264. doi: 10.1016/j.bbih.2021.100264. PMID: 34589770; PMCID: PMC8474574. https://pubmed.ncbi.nlm.nih.gov/34589770/

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/

Neuroinflammation, Oxidative Stress, and Neurogenesis in a Mouse Model of Chronic Fatigue Syndrome, and the Treatment with Kampo Medicine

Abstract:

The diagnosis of chronic fatigue syndrome (CFS) is mainly symptom-based, and the etiology is still unclear. Here, we evaluated the pathological changes in the brain of a mouse model of CFS and studied the effects of Kampo medicine.

A mouse model of CFS was established through six repeated injections of Brucella abortus (BA) every two weeks for a period of 12 weeks. Neuroinflammation was measured by estimating interleukin (IL)-1β, IL-6, and interferon-gamma (IFN-γ), and oxidative stress by nitrotyrosine (3-NT) and 4-hydroxynonenal (4-HNE) 6 weeks after the last injection. Hippocampal neurogenesis was evaluated through Ki-67, doublecortin (DCX), and 5-bromodeoxyuridine (BrdU) assays. The effects of Kampo medicines (Hochuekkito (TJ-41) and Hachimijiogan (TJ-7)) on neuroinflammation during CFS were studied.

The wheel-running activity of mice was decreased by about 50% compared to baseline at 6 weeks after the last BA injection. The levels of IL-1β, IL-6, 3-NT, and 4-HNE were increased in both the cortex and the hippocampus of CFS mice at 6 weeks after the last BA injection. Hippocampal neurogenesis was unchanged in CFS mice. Treatment with TJ-41 and TJ-7 reduced the expressions of IL-1β, IL-6, and IFN-γ in the hippocampus but not in the cortex.

The results of the present study indicate that neuroinflammation and oxidative stress play important roles in the pathogenesis of CFS. The data further suggest that treatment with TJ-41 and TJ-7 could help reduce the inflammation associated with CFS in the hippocampus, but failed to improve the symptoms in CFS mice.

Source: He Q, Sawada M, Yamasaki N, Akazawa S, Furuta H, Uenishi H, Meng X, Nakahashi T, Ishigaki Y, Moriya J. Neuroinflammation, Oxidative Stress, and Neurogenesis in a Mouse Model of Chronic Fatigue Syndrome, and the Treatment with Kampo Medicine. Biol Pharm Bull. 2020;43(1):110-115. doi: 10.1248/bpb.b19-00616. https://www.jstage.jst.go.jp/article/bpb/43/1/43_b19-00616/_article (Full article)

The role of low-grade inflammation in ME/CFS (Myalgic Encephalomyelitis/Chronic Fatigue Syndrome) – associations with symptoms

Abstract:

BACKGROUND: Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) often present with a range of flu-like symptoms resembling sickness behavior as well as widespread pain and concentration deficits. The aim of this study was to explore the association between inflammatory markers previously shown to be related to fatigue severity in ME/CFS and common ME/CFS symptoms post-exertional fatigue, impaired cognitive processing, musculoskeletal pain and recurrent flu-like symptoms, and the moderating effect of sex on these associations.

METHODS: 53 adult patients diagnosed with ME/CFS at a specialist clinic were included in the study. Fasting blood plasma was analyzed using the Olink Proseek Multiplex Inflammation panel (β-NGF, CCL11, CXCL1, CXCL10, IL-6, IL-7, IL-8, IL-10, IL-18, TGF-α, TGF-β-1 and SCF) and BioRad Human Cytokine Type 1 assay (TNF-α). Participants rated the average severity of symptoms (0-10) based on the 2011 International Consensus Criteria of ME/CFS during a structured clinical interview. Associations between inflammatory markers and symptom severity were analyzed using bivariate correlations and moderated regression analyses bootstrapped with 5000 repetitions.

RESULTS AND CONCLUSIONS: Only β-NGF was associated with the fatigue severity measure. However, higher levels of CCL11, CXCL10, IL-7, TNF-α and TGF-β-1 were significantly associated with higher levels of impaired cognitive processing and musculoskeletal pain, and sex was a significant moderator for CXCL10, IL-7 and TGF-β-1. Future studies should investigate the relationship between inflammatory markers and key symptoms in ME/CFS in a longitudinal design in order to explore if and for whom low-grade inflammation may contribute to illness development.

Copyright © 2019. Published by Elsevier Ltd.

Source: Jonsjö MA, Olsson GL, Wicksell RK, Alving K, Holmström L, Andreasson A. The role of low-grade inflammation in ME/CFS (Myalgic Encephalomyelitis/Chronic Fatigue Syndrome) – associations with symptoms. Psychoneuroendocrinology. 2019 Dec 26;113:104578. doi: 10.1016/j.psyneuen.2019.104578. [Epub ahead of print] https://www.sciencedirect.com/science/article/pii/S0306453019313198?via%3Dihub (Full article)

Modification of Immunological Parameters, Oxidative Stress Markers, Mood Symptoms, and Well-Being Status in CFS Patients after Probiotic Intake: Observations from a Pilot Study

Abstract:

The present study discusses about the effects of a combination of probiotics able to stimulate the immune system of patients affected by Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). To this purpose, patients diagnosed according to Fukuda’s criteria and treated with probiotics were analyzed by means of clinical and laboratory evaluations, before and after probiotic administrations.

Probiotics were selected considering the possible pathogenic mechanisms of ME/CFS syndrome, which has been associated with an impaired immune response, dysregulation of Th1/Th2 ratio, and high oxidative stress with exhaustion of antioxidant reserve due to severe mitochondrial dysfunction. Immune and oxidative dysfunction could be related with the gastrointestinal (GI) chronic low-grade inflammation in the lamina propria and intestinal mucosal surface associated with dysbiosis, leaky gut, bacterial translocation, and immune and oxidative dysfunction.

Literature data demonstrate that bacterial species are able to modulate the functions of the immune and oxidative systems and that the administration of some probiotics can improve mucosal barrier function, modulating the release of proinflammatory cytokines, in CFS/ME patients. This study represents a preliminary investigation to verifying the safety and efficacy of a certain combination of probiotics in CFS/ME patients. The results suggest that probiotics can modify the well-being status as well as inflammatory and oxidative indexes in CFS/ME patients.

No adverse effects were observed except for one patient, which displayed a flare-up of symptoms, although all inflammatory parameters (i.e., cytokines, fecal calprotectin, ESR, and immunoglobulins) were reduced after probiotic intake. The reactivation of fatigue symptoms in this patient, whose clinical history reported the onset of CFS/ME following mononucleosis, could be related to an abnormal stimulation of the immune system as suggested by a recent study describing an exaggerated immune activation associated with chronic fatigue.

Copyright © 2019 Letizia Venturini et al.

Source: Venturini L, Bacchi S, Capelli E, Lorusso L, Ricevuti G, Cusa C. Modification of Immunological Parameters, Oxidative Stress Markers, Mood Symptoms, and Well-Being Status in CFS Patients after Probiotic Intake: Observations from a Pilot Study. Oxid Med Cell Longev. 2019 Nov 23;2019:1684198. doi: 10.1155/2019/1684198. eCollection 2019. https://www.hindawi.com/journals/omcl/2019/1684198/ (Full study)

Patients with ME/CFS (Myalgic Encephalomyelitis/Chronic Fatigue Syndrome) and chronic pain report similar level of sickness behavior as individuals injected with bacterial endotoxin at peak inflammation

Abstract:

Background: Chronic sickness behavior is implicated in ME/CFS (Myalgic Encephalomyelitis/Chronic Fatigue Syndrome) and chronic pain but the level of subjective sickness behavior in these conditions has not been investigated or compared to other clinical and non-clinical samples, or to the level in experimental inflammation. Furthermore, the relationship between sickness behavior and self-rated health and functioning is not known in patients with ME/CFS and chronic pain. The aim of the present study was to investigate how sickness behavior in patients with chronic conditions differs from that in individuals with experimental acute sickness, primary care patients, the general population and healthy subjects. In addition, we wanted to explore how sickness behavior is related to self-rated health and health-related functioning.

Methods: Sickness behavior was quantified using the sickness questionnaire (SicknessQ). Self-ratings were collected at one time-point in 6 different samples. Levels of sickness behavior in patients with ME/CFS (n=38) and patients with chronic pain (n=190) were compared to healthy subjects with lipopolysaccharide(LPS)-induced inflammation (n=29), primary care patients (n=163), individuals from the general population (n=155) and healthy subjects (n=48), using linear regression. Correlations and moderated regression analyses were used to investigate associations between sickness behavior and self-rated health and health-related functioning in ME/CFS, chronic pain and the general population.

Results: LPS-injected individuals (M=16.3), patients with ME/CFS (M=16.1), chronic pain (M=16.1) and primary care patients (M=10.7) reported significantly higher SicknessQ scores than individuals from the general population (M=5.4) and healthy subjects (M=3.6) all p’s<0.001). In turn, LPS-injected individuals, patients with ME/CFS and chronic pain reported significantly higher SicknessQ scores than primary care patients (p’s<0.01). Higher levels of sickness behavior were associated with poorer self-rated health and health-related functioning (p’s<0.01), but less so in patients with ME/CFS and chronic pain than in individuals from the general population.

Conclusions: Patients with ME/CFS and chronic pain report similar high levels of sickness behavior; higher than primary care patients, and comparable to levels in experimental inflammation. Further study of sickness behavior in ME/CFS and chronic pain populations is warranted as immune-to-brain interactions and sickness behavior may be of importance for functioning as well as in core pathophysiological processes in subsets of patients.

Source: Martin A.Jonsjö, JennyÅström, Michael P.Jones, Bianka Karshikoff, Karin Lodin, Linda Holmström, Lars Agréus, Rikard K.Wicksell, John Axelsson, Mats Lekander, Gunnar L.Olsson, Mike Kemani, Anna Andreasson. Patients with ME/CFS (Myalgic Encephalomyelitis/Chronic Fatigue Syndrome) and chronic pain report similar level of sickness behavior as individuals injected with bacterial endotoxin at peak inflammation. Brain, Behavior, & Immunity – Health. Available online 17 December 2019, 100028. https://www.sciencedirect.com/science/article/pii/S2666354619300298  (Full study)

Inflammatory proteins are altered in chronic fatigue syndrome-A systematic review and meta-analysis

Abstract:

Immune dysfunction has been posited as a key element in the aetiology of chronic fatigue syndrome (CFS) since the illness was first conceived. However, systematic reviews have yet to quantitatively synthesise inflammatory biomarkers across the literature. We undertook a systematic review and meta-analysis to quantify available data on circulating inflammatory proteins, examining studies recruiting patients with a CFS diagnosis and a non-affected control group. Results were meta-analysed from 42 studies.

Patients with CFS had significantly elevated tumour necrosis factor (ES = 0.274, p < 0.001), interleukin-2 (ES = 0.203, p = 0.006), interleukin-4 (ES = 0.373, p = 0.004), transforming growth factor-β (ES = 0.967, p < 0.001) and c-reactive protein (ES = 0.622, p = 0.019). 12 proteins did not differ between groups.

These data provide some support for an inflammatory component in CFS, although inconsistency of results indicates that inflammation is unlikely to be a primary feature in all those suffering from this disorder. It is hoped that further work will elucidate whether there are subgroups of patients with clinically-relevant inflammatory dysfunction, and whether inflammatory cytokines may provide a prognostic biomarker or moderate treatment effects.

Copyright © 2019. Published by Elsevier Ltd.

Source: Strawbridge R, Sartor ML, Scott F, Cleare AJ. Inflammatory proteins are altered in chronic fatigue syndrome-A systematic review and meta-analysis. Neurosci Biobehav Rev. 2019 Aug 26;107:69-83. doi: 10.1016/j.neubiorev.2019.08.011. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31465778

MicroRNAs as biomarkers of pain intensity in patients with chronic fatigue syndrome

Abstract:

BACKGROUND: Numerous experimental models have shown that microRNAs play an important role in regulating pain-processing in clinical pain disorders. In this study, we evaluated a set of micro-RNAs as diagnostic biomarkers of pain intensity in adolescents with chronic fatigue syndrome (CFS). We then correlated the expression of these microRNAs with the levels of inflammatory markers and pain-related comorbidities in adolescents with CSF and healthy controls (HCs).

METHODS: A total of 150 adolescents, aged 12-18 years, participated in this study between April 2016 and April 2017. The participants were classified into two groups: adolescents with CFS (n=100) and HCs (n=50). RT-PCR was used to evaluate the expression of miR-558, miR-146a, miR-150, miR-124, and miR-143. Immunoassay analysis was used to assess the levels of immune inflammatory markers IL-6, TNF-α, and COX-2.

RESULTS: Adolescents with CFS showed significantly higher pain thresholds than comparable non-fatigued HCs. Also, enjoy of life and relation to others as the life domains, showed lower pain interference in CFS patients. Differential expression of miR-558, miR-146a, miR-150, miR-124, and miR-143 was significantly down regulated and notably interfered with pain intensity and frequency in patients with CFS. Also, the expression of these miRNAs was significantly correlated with that of IL-6, TNF-α, and COX-2, which have been shown to mediate pain intensity in patients with CFS.

Girls with CSF showed significantly decreased expression levels of these miRNAs compared with the levels of boys with CSF. Girls with CSF also showed increased expression of inflammatory pain-related markers IL-6, TNF-α, and COX-2, compared with the levels of boys with CSF

CONCLUSIONS: The intensity and consequences of pain were influenced by differential expression of miR-558, miR-146a, miR-150, miR-124, and miR-143, which was directly, associated with higher expression of immune inflammatory related genes TNFα, IL-6, and COX-2 in adolescences with CFS. Further studies of larger patient cohorts will help clarify the role of miRNAs in the pathogenesis of CFS.

This article is protected by copyright. All rights reserved.

Source: Al-Rawaf HA, Alghadir AH, Gabr SA. MicroRNAs as biomarkers of pain intensity in patients with chronic fatigue syndrome. Pain Pract. 2019 Jul 8. doi: 10.1111/papr.12817. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31282597

Shared microglial mechanisms underpinning depression and chronic fatigue syndrome and their comorbidities

Abstract:

In 2011, it was reviewed that a) there is a strong co-occurrence between major depression and chronic fatigue syndrome (CFS), with fatigue and physio-somatic symptoms being key symptoms of depression, and depressive symptoms appearing during the course of CFS; and b) the comorbidity between both disorders may in part be explained by activated immune-inflammatory pathways, including increased translocation of Gram-negative bacteria and increased levels of pro-inflammatory cytokines, such as interleukin (IL)-1. Nevertheless, the possible involvement of activated microglia in this comorbidity has remained unclear.

This paper aims to review microglial disturbances in major depression, CFS and their comorbidity. A comprehensive literature search was conducted using the PubMed / MEDLINE database to identify studies, which are relevant to this current review. Depressed patients present neuroinflammatory alterations, probably related to microglial activation, while animal models show that a microglial response to immune challenges including lipopolysaccharides is accompanied by depressive-like behaviors. Recent evidence from preclinical studies indicates that activated microglia have a key role in the onset of fatigue. In chronic inflammatory conditions, such as infections and senescence, microglia orchestrate an inflammatory microenvironment thereby causing fatigue.

In conclusion, based on our review we may posit that shared immune-inflammatory pathways and especially activated microglia underpin comorbid depression and CFS. As such, microglial activation and neuro-inflammation may be promising targets to treat the overlapping manifestations of both depression and CFS.

Copyright © 2019. Published by Elsevier B.V.

Source: Filho AJMC, Macedo DS, de Lucena DF, Maes M. Shared microglial mechanisms underpinning depression and chronic fatigue syndrome and their comorbidities. Behav Brain Res. 2019 May 25:111975. doi: 10.1016/j.bbr.2019.111975. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31136774

Cytokine profiles in patients with Q fever fatigue syndrome

Abstract:

Background: Q fever fatigue syndrome (QFS) is a state of prolonged fatigue following around 20% of acute Q fever cases. It is thought that chronic inflammation plays a role in its aetiology. To test this hypothesis we measured circulating cytokines and the exvivo cytokine production in patients with QFS and compared to various control groups.

Materials/methods: Peripheral blood mononuclear cells (PBMCs), whole blood, and serum were collected from 20 QFS patients, 19 chronic fatigue syndrome (CFS) patients, 19 Q fever seropositive controls, and 25 age- and sex-matched healthy controls. Coxiella-specific ex-vivo production of tumor necrosis factor (TNF)α, interleukin (IL)-1β, IL-6, and interferon (IFN) was measured, together with a total of 92 circulating inflammatory proteins.

Results: PBMCs of QFS patients produced more IL-6 (P = 0.0001), TNFα (P = 0.0002), and IL-1β (P = 0.0005) than the various control groups when stimulated with Coxiella antigen. QFS patients had distinct differences in circulating inflammatory markers compared to the other groups, including higher concentrations of circulating IL-6 and IFNγ.

Conclusion: QFS patients showed signs of chronic inflammation compared to asymptomatic Q fever seropositive controls, CFS patients, and healthy controls, of which the monocyte-derived cytokines TNFα, IL-1β, and especially IL-6, are likely crucial components.

Source: Raijmakers, Ruud P.H. et al. Cytokine profiles in patients with Q fever fatigue syndrome. Journal of Infection , Volume 0 , Issue 0 , DOI: https://doi.org/10.1016/j.jinf.2019.01.006