CD4 T lymphocytes from patients with chronic fatigue syndrome have decreased interferon-gamma production and increased sensitivity to dexamethasone

Adrenalectomy attenuates hyperalgesia but does not regulate muscle wasting in a female rat model of fibromyalgia

Although it is well established that fibromyalgia (FM) syndrome is characterized by chronic diffuse musculoskeletal hyperalgesia, very little is known about the effect of this pathology on muscle tissue plasticity. Therefore, the present study aimed to characterize the putative alterations in skeletal muscle mass in female rats subjected to a FM model by inducing chronic diffuse hyperalgesia (CDH) through double injections of acidic saline (pH 4.0) into the left gastrocnemius muscle at 5-day intervals. To determine protein turnover, the total proteolysis, proteolytic system activities and protein synthesis were evaluated in oxidative soleus muscles of pH 7.2 (control) and pH 4.0 groups at 7 days after CDH induction. All animals underwent behavioural analyses of mechanical hyperalgesia, strength and motor performance. Our results demonstrated that, in addition to hyperalgesia, rats injected with acidic saline exhibited skeletal muscle loss, as evidenced by a decrease in the soleus fibre cross-sectional area. This muscle loss was associated with increased proteasomal proteolysis and expression of the atrophy-related gene (muscle RING-finger protein-1), as well as reduced protein synthesis and decreased protein kinase B/S6 pathway activity. Although the plasma corticosterone concentration did not differ between the control and pH 4.0 groups, the removal of the adrenal glands attenuated hyperalgesia, but it did not prevent the increase in muscle protein loss in acidic saline-injected animals. The data suggests that the stress-related hypothalamic-pituitary-adrenal axis is involved in the development of hyperalgesia, but is not responsible for muscle atrophy observed in the FM model induced by intramuscular administration of acidic saline. Although the mechanisms involved in the attenuation of hyperalgesia in rats injected with acidic saline and subjected to adrenalectomy still need to be elucidated, the results found in this study suggest that glucocorticoids may not represent an effective therapeutic approach to alleviate FM symptoms.

Analysis of post COVID-19 condition and its overlap with myalgic encephalomyelitis/chronic fatigue syndrome

BACKGROUND

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease (COVID-19) triggers the development of numerous pathologies and infection-linked complications and exacerbates existing pathologies in nearly all body systems. Aside from the primarily targeted respiratory organs, adverse SARS-CoV-2 effects were observed in nervous, cardiovascular, gastrointestinal/metabolic, immune, and other systems in COVID-19 survivors. Long-term effects of this viral infection have been recently observed and represent distressing sequelae recognised by the World Health Organisation (WHO) as a distinct clinical entity defined as post-COVID-19 condition. Considering the pandemic is still ongoing, more time is required to confirm post COVID-19 condition diagnosis in the COVID-19 infected cohorts, although many reported post COVID-19 symptoms overlap with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

AIMS OF REVIEW

In this study, COVID-19 clinical presentation and associated post-infection sequelae (post-COVID-19 condition) were reviewed and compared with ME/CFS symptomatology.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The onset, progression, and symptom profile of post COVID-19 condition patients have considerable overlap with ME/CFS. Considering the large scope and range of pro-inflammatory effects of this virus, it is reasonable to expect development of post COVID-19 clinical complications in a proportion of the affected population. There are reports of a later debilitating syndrome onset three months post COVID-19 infection (often described as long-COVID-19), marked by the presence of fatigue, headache, cognitive dysfunction, post-exertional malaise, orthostatic intolerance, and dyspnoea. Acute inflammation, oxidative stress, and increased levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNFα), have been reported in SARS-CoV-2 infected patients. Longitudinal monitoring of post COVID-19 patients is warranted to understand the long-term effects of SARS-CoV-2 infection and the pathomechanism of post COVID-19 condition.

Repositioned Drugs for COVID-19-the Impact on Multiple Organs

This review summarizes published findings of the beneficial and harmful effects on the heart, lungs, immune system, kidney, liver, and central nervous system of 47 drugs that have been proposed to treat COVID-19. Many of the repurposed drugs were chosen for their benefits to the pulmonary system, as well as immunosuppressive and anti-inflammatory effects. However, these drugs have mixed effects on the heart, liver, kidney, and central nervous system. Drug treatments are critical in the fight against COVID-19, along with vaccines and public health protocols. Drug treatments are particularly needed as variants of the SARS-Cov-2 virus emerge with some mutations that could diminish the efficacy of the vaccines. Patients with comorbidities are more likely to require hospitalization and greater interventions. The combination of treating severe COVID-19 symptoms in the presence of comorbidities underscores the importance of understanding the effects of potential COVID-19 treatments on other organs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42399-021-00874-8.

Myalgic encephalomyelitis/chronic fatigue syndrome patients exhibit altered T cell metabolism and cytokine associations

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disease with no known cause or mechanism. There is an increasing appreciation for the role of immune and metabolic dysfunction in the disease. ME/CFS has historically presented in outbreaks, often has a flu-like onset, and results in inflammatory symptoms. Patients suffer from severe fatigue and postexertional malaise. There is little known about the metabolism of specific immune cells in patients with ME/CFS. To investigate immune metabolism in ME/CFS, we isolated CD4+ and CD8+ T cells from 53 patients with ME/CFS and 45 healthy controls. We analyzed glycolysis and mitochondrial respiration in resting and activated T cells, along with markers related to cellular metabolism and plasma cytokines. We found that ME/CFS CD8+ T cells had reduced mitochondrial membrane potential compared with those from healthy controls. Both CD4+ and CD8+ T cells from patients with ME/CFS had reduced glycolysis at rest, whereas CD8+ T cells also had reduced glycolysis following activation. Patients with ME/CFS had significant correlations between measures of T cell metabolism and plasma cytokine abundance that differed from correlations seen in healthy control subjects. Our data indicate that patients have impaired T cell metabolism consistent with ongoing immune alterations in ME/CFS that may illuminate the mechanism behind this disease.

Epstein-Barr Virus Induced Gene-2 Upregulation Identifies a Particular Subtype of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is a chronic multisystem disease characterized by a variety of symptoms, and exhibits various features of an autoimmune-like disease. Subtypes are well recognized but to date are difficult to identify objectively. The disease may be triggered by infection with a variety of micro-organisms, including Epstein-Barr virus (EBV). A subset of CFS/ME patients exhibit up regulation of EBV virus induced gene 2 (EBI2) mRNA in peripheral blood mononuclear cells (PBMC), and these patients appear to have a more severe disease phenotype and lower levels of EBNA1 IgG. EBI2 is induced by EBV infection and has been found to be upregulated in a variety of autoimmune diseases. EBI2 is a critical gene in immunity and central nervous system function; it is a negative regulator of the innate immune response in monocytes. Its heterogeneous expression in CFS/ME could explain the variable occurrence of a variety of immune and neurological abnormalities which are encountered in patients with CFS/ME. The EBI2 subtype occurred in 38-55% CFS/ME patients in our studies. Further work is required to confirm the role of EBV and of EBI2 and its oxysterol ligands in CFS/ME, and to identify the most practical means to identify patients of the EBI subtype. There are two EBI2 antagonists currently in development, and these may hold promise in the treatment of CFS/ME patients of the EBI subtype.

Genome-epigenome interactions associated with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex disease of unknown etiology. Multiple studies point to disruptions in immune functioning in ME/CFS patients as well as specific genetic polymorphisms and alterations of the DNA methylome in lymphocytes. However, potential interactions between DNA methylation and genetic background in relation to ME/CFS have not been examined. In this study we explored this association by characterizing the epigenetic (~480 thousand CpG loci) and genetic (~4.3 million SNPs) variation between cohorts of ME/CFS patients and healthy controls. We found significant associations of DNA methylation states in T-lymphocytes at several CpG loci and regions with ME/CFS phenotype. These methylation anomalies are in close proximity to genes involved with immune function and cellular metabolism. Finally, we found significant correlations of genotypes with methylation modifications associated with ME/CFS. The findings from this study highlight the role of epigenetic and genetic interactions in complex diseases, and suggest several genetic and epigenetic elements potentially involved in the mechanisms of disease in ME/CFS.

Reduction of Glucocorticoid Receptor Function in Chronic Fatigue Syndrome

Glucocorticoid receptor (GR) function may have aetiopathogenic significance in chronic fatigue syndrome (CFS), via its essential role in mediating inflammatory responses as well as in hypothalamic-pituitary-adrenal axis regulation. GR function can be estimated ex vivo by measuring dexamethasone (dex) modulation of cytokine response to lipopolysaccharide (LPS), and in vivo using the impact of dex on cortisol levels. This study aimed to compare the GR function between CFS (n = 48), primary Sjögren's syndrome (a disease group control) (n = 27), and sedentary healthy controls (HCs) (n = 20), and to investigate its relationship with clinical measures. In the GR ex vivo response assay, whole blood was diluted and incubated with LPS (to stimulate cytokine production), with or without 10 or 100 nanomolar concentrations of dex. Cytometric bead array (CBA) and flow cytometry enabled quantification of cytokine levels (TNFα, interleukin- (IL-) 6, and IL-10) in the supernatants. In the in vivo response assay, five plasma samples were taken for determination of total cortisol concentration using ELISA at half-hourly intervals on two consecutive mornings separated by ingestion of 0.5 mg of dex at 11 pm. The association of the data from the in vivo and ex vivo analyses with reported childhood adversity was also examined. CFS patients had reduced LPS-induced IL-6 and TNFα production compared to both control groups and reduced suppression of TNFα by the higher dose of dex compared to HCs. Cortisol levels, before or after dex, did not differ between CFS and HCs. Cortisol levels were more variable in CFS than HCs. In the combined group (CFS plus HC), cortisol concentrations positively and ex vivo GR function (determined by dex-mediated suppression of IL-10) negatively correlated with childhood adversity score. The results do not support the hypothesis that GR dysregulation is aetiopathogenic in CFS and suggest that current and future endocrine cross-sectional studies in CFS may be vulnerable to the confounding influence of childhood trauma which is likely increased by comorbid depression.

Epigenetic modifications and glucocorticoid sensitivity in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Background

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating idiopathic disease characterized by unexplained fatigue that fails to resolve with sufficient rest. Diagnosis is based on a list of symptoms and exclusion of other fatigue-related health conditions. Despite a heterogeneous patient population, immune and hypothalamic-pituitary-adrenal (HPA) axis function differences, such as enhanced negative feedback to glucocorticoids, are recurring findings in ME/CFS studies. Epigenetic modifications, such as CpG methylation, are known to regulate long-term phenotypic differences and previous work by our group found DNA methylome differences in ME/CFS, however the relationship between DNA methylome modifications, clinical and functional characteristics associated with ME/CFS has not been examined.

Methods

We examined the DNA methylome in peripheral blood mononuclear cells (PBMCs) of a larger cohort of female ME/CFS patients using the Illumina HumanMethylation450 BeadChip Array. In parallel to the DNA methylome analysis, we investigated in vitro glucocorticoid sensitivity differences by stimulating PBMCs with phytohaemagglutinin and suppressed growth with dexamethasone. We explored DNA methylation differences using bisulfite pyrosequencing and statistical permutation. Linear regression was implemented to discover epigenomic regions associated with self-reported quality of life and network analysis of gene ontology terms to biologically contextualize results.

Results

We detected 12,608 differentially methylated sites between ME/CFS patients and healthy controls predominantly localized to cellular metabolism genes, some of which were also related to self-reported quality of life health scores. Among ME/CFS patients, glucocorticoid sensitivity was associated with differential methylation at 13 loci.

Conclusions

Our results indicate DNA methylation modifications in cellular metabolism in ME/CFS despite a heterogeneous patient population, implicating these processes in immune and HPA axis dysfunction in ME/CFS. Modifications to epigenetic loci associated with differences in glucocorticoid sensitivity may be important as biomarkers for future clinical testing. Overall, these findings align with recent ME/CFS work that point towards impairment in cellular energy production in this patient population.

Electronic supplementary material

The online version of this article (doi:10.1186/s12920-017-0248-3) contains supplementary material, which is available to authorized users.

Hypothalamic-Pituitary-Adrenal Hypofunction in Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS) as a Consequence of Activated Immune-Inflammatory and Oxidative and Nitrosative Pathways

There is evidence that immune-inflammatory and oxidative and nitrosative stress (O&NS) pathways play a role in the pathophysiology of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (CFS). There is also evidence that these neuroimmune diseases are accompanied by hypothalamic-pituitary-adrenal (HPA) axis hypoactivity as indicated by lowered baseline glucocorticoid levels. This paper aims to review the bidirectional communications between immune-inflammatory and O&NS pathways and HPA axis hypoactivity in ME/CFS, considering two possibilities: (a) Activation of immune-inflammatory pathways is secondary to HPA axis hypofunction via attenuated negative feedback mechanisms, or (b) chronic activated immune-inflammatory and O&NS pathways play a causative role in HPA axis hypoactivity. Electronic databases, i.e., PUBMED, Scopus, and Google Scholar, were used as sources for this narrative review by using keywords CFS, ME, cortisol, ACTH, CRH, HPA axis, glucocorticoid receptor, cytokines, immune, immunity, inflammation, and O&NS. Findings show that activation of immune-inflammatory and O&NS pathways in ME/CFS are probably not secondary to HPA axis hypoactivity and that activation of these pathways may underpin HPA axis hypofunction in ME/CFS. Mechanistic explanations comprise increased levels of tumor necrosis factor-α, T regulatory responses with elevated levels of interleukin-10 and transforming growth factor-β, elevated levels of nitric oxide, and viral/bacterial-mediated mechanisms. HPA axis hypoactivity in ME/CFS is most likely a consequence and not a cause of a wide variety of activated immune-inflammatory and O&NS pathways in that illness.

Fatigue in primary Sjögren's syndrome is associated with lower levels of proinflammatory cytokines

Objectives

This article reports relationships between serum cytokine levels and patient-reported levels of fatigue, in the chronic immunological condition primary Sjögren's syndrome (pSS).

Methods

Blood levels of 24 cytokines were measured in 159 patients with pSS from the United Kingdom Primary Sjögren's Syndrome Registry and 28 healthy non-fatigued controls. Differences between cytokines in cases and controls were evaluated using Wilcoxon test. Patient-reported scores for fatigue were evaluated, classified according to severity and compared with cytokine levels using analysis of variance. Logistic regression was used to determine the most important predictors of fatigue levels.

Results

14 cytokines were significantly higher in patients with pSS (n=159) compared to non-fatigued healthy controls (n=28). While serum levels were elevated in patients with pSS compared to healthy controls, unexpectedly, the levels of 4 proinflammatory cytokines—interferon-γ-induced protein-10 (IP-10) (p=0.019), tumour necrosis factor-α (p=0.046), lymphotoxin-α (p=0.034) and interferon-γ (IFN-γ) (p=0.022)—were inversely related to patient-reported levels of fatigue. A regression model predicting fatigue levels in pSS based on cytokine levels, disease-specific and clinical parameters, as well as anxiety, pain and depression, revealed IP-10, IFN-γ (both inversely), pain and depression (both positively) as the most important predictors of fatigue. This model correctly predicts fatigue levels with reasonable (67%) accuracy.

Conclusions

Cytokines, pain and depression appear to be the most powerful predictors of fatigue in pSS. Our data challenge the notion that proinflammatory cytokines directly mediate fatigue in chronic immunological conditions. Instead, we hypothesise that mechanisms regulating inflammatory responses may be important.

Serum Immune Proteins in Moderate and Severe Chronic Fatigue Syndrome/Myalgic Encephalomyelitis Patients

Immunological dysregulation is present in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), with recent studies also highlighting the importance of examining symptom severity. This research addressed this relationship between CFS/ME severity subgroups, assessing serum immunoglobulins and serum cytokines in severe and moderate CFS/ME patients. Participants included healthy controls (n= 22), moderately (n = 22) and severely (n=19) affected CFS/ME patients. The 1994 Fukuda Criteria defined CFS/ME and severity scales confirmed mobile and housebound CFS/ME patients as moderate and severe respectively. IL-1β was significantly reduced in severe compared with moderate CFS/ME patients. IL-6 was significantly decreased in moderate CFS/ME patients compared with healthy controls and severe CFS/ME patients. RANTES was significantly increased in moderate CFS/ME patients compared to severe CFS/ME patients. Serum IL-7 and IL-8 were significantly higher in the severe CFS/ME group compared with healthy controls and moderate CFS/ME patients. IFN-γ was significantly increased in severe CFS/ME patients compared with moderately affected patients. This was the first study to show cytokine variation in moderate and severe CFS/ME patients, with significant differences shown between CFS/ME symptom severity groups. This research suggests that distinguishing severity subgroups in CFS/ME research settings may allow for a more stringent analysis of the heterogeneous and otherwise inconsistent illness.

Glucocorticoid sensitivity of leukocytes predicts PTSD, depressive and fatigue symptoms after military deployment: A prospective study

AIM

Posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and severe fatigue may develop in response to severe stress and trauma. These conditions have all been shown to be associated with altered sensitivity of leukocytes for regulation by glucocorticoids (GCs). However, it remains unknown whether sensitivity of leukocytes for GCs is a pre-existing vulnerability factor, or whether GC-sensitivity of leukocytes alters as a consequence of stress and stress-related conditions. Our aim was to investigate whether sensitivity of T-cells and monocytes for regulation by GCs (i.e. dexamethasone: DEX) assessed before military deployment predicts high levels of PTSD, depressive, and/or fatigue symptoms 6 months after return from deployment.

METHODS

We included 526 male military personnel before deployment to Afghanistan. Logistic regression analysis was performed to predict fatigue, depressive, and PTSD symptoms 6 months after deployment based on sensitivity of LPS-induced TNF-α production and PHA-induced T-cell proliferation to DEX-inhibition before deployment.

RESULTS

Severe fatigue 6 months after deployment was independently associated with low DEX-sensitivity of monocyte TNF-α production before deployment. A high level of depressive symptoms after deployment was independently associated with a low DEX-sensitivity of T-cell proliferation. In contrast, a high level of PTSD symptoms after deployment was independently associated with a high DEX-sensitivity of T-cell proliferation before deployment, but only in individuals who reported PTSD symptoms without depressive symptoms. The predictive value of DEX-sensitivity was independent of childhood trauma and GR number, GR subtype and GR target gene mRNA expression in leukocytes.

CONCLUSIONS

We present here for the first time that the sensitivity of leukocytes for GCs prior to deployment is a predictive factor for the development of PTSD, depressive and fatigue symptomatology in response to deployment. Notably, PTSD, depressive and fatigue symptoms were differentially associated with GC-sensitivity of monocytes and T-cells and therefore may have different biological underpinnings.

Four-Item Fatigue Screen

Introduction:

To develop a shorter and less burdensome cancer-related fatigue (CRF) questionnaire, the Four-Item Fatigue Scale (FIFS) was tested for validity against the Brief Fatigue Index (BFI).

Methods:

On day 1, patients with cancer completed the BFI and FIFS in a random order and the reverse on day 7. Sixty-five patients were needed for an 80% power and a Spearman correlation of .7 or greater. The FIFS was compared with the BFI in fatigue severity and changes in fatigue over time. Bonferroni corrections were made for multiple comparisons with International Classification of Diseases, Tenth Revision ( ICD-10) fatigue criteria.

Results:

Seventy-nine patients were enrolled, 65 patients completed both surveys. Spearman correlation between FIFS and BFI for day 1 was 0.69 (95% confidence interval [CI] 0.50-0.87) and 0.73 (95% CI 0.56-0.90) 1 week later. Fatigue severity did not predict survival with either questionnaire. Brief Fatigue Index severity correlated with ICD-10 items 1, 3, 7, and 10B. Regression analysis showed that on day 7 BFI correlated with ICD-10 items 1, 7, and 10. When the model was adjusted for day 1, only the ICD-10 item 5 correlated well in BFI over 1 week. The ICD-10 items 7 and 10 significantly correlated with day 1 FIFS fatigue changes over 7 days after adjustment for FIFS baseline score.

Conclusions:

Four-Item Fatigue Scale has concurrent validity for fatigue using the BFI. The FIFS and BFI correlated modestly over time. Certain ICD-10 items correlated with CRF severity depending on the questionnaire.

Hypothalamic-pituitary-adrenal axis dysfunction in chronic fatigue syndrome

The weight of current evidence supports the presence of the following factors related to hypothalamic-pituitary-adrenal (HPA) axis dysfunction in patients with chronic fatigue syndrome (CFS): mild hypocortisolism; attenuated diurnal variation of cortisol; enhanced negative feedback to the HPA axis; and blunted HPA axis responsiveness. Furthermore, HPA axis changes seem clinically relevant, as they are associated with worse symptoms and/or disability and with poorer outcomes to standard treatments for CFS. Regarding etiology, women with CFS are more likely to have reduced cortisol levels. Studies published in the past 8 years provide further support for a multifactorial model in which several factors interact to moderate HPA axis changes. In particular, low activity levels, depression and early-life stress appear to reduce cortisol levels, whereas the use of psychotropic medication can increase cortisol. Addressing these factors-for example, with cognitive behavioral therapy-can increase cortisol levels and is probably the first-line approach for correcting HPA axis dysfunction at present, as steroid replacement is not recommended. Given what is now a fairly consistent pattern of findings for the type of HPA axis changes found in CFS, we recommend that future work focuses on improving our understanding of the cause and relevance of these observed changes.

Glucocorticoid receptor mediated negative feedback in chronic fatigue syndrome using the low dose (0.5 mg) dexamethasone suppression test

BACKGROUND

Chronic fatigue syndrome (CFS) is associated with hypocortisolism, but it is not yet clear the extent to which enhanced negative feedback may underlie this finding.

METHODS

We undertook a low-dose dexamethasone (0.5 mg) suppression test in 18 CFS patients and 20 matched, healthy controls. We measured salivary cortisol levels at 0800 h, 1200 h, 1600 h and 2000 h before and after the administration of 0.5 mg of dexamethasone.

RESULTS

Basal cortisol output was raised in this group of CFS patients compared to controls. Overall, the percentage suppression following dexamethasone administration was no different between CFS (mean+/-sem: 80.4+/-4.4%) and controls (76.2+/-4.9 %). However, the sub-group of patients with CFS and comorbid depression (n=9) showed a significant hypersuppression of salivary cortisol in response to dexamethasone (89.0+/-1.9%; p<0.05 v controls).

LIMITATIONS

The sub-group analysis was on small numbers and should be considered preliminary. Dexamethasone probes only glucocorticoid medicated negative feedback but does not probe mineralocorticoid feedback, the other main physiological feedback mechanism.

CONCLUSION

We found partial support for the hypothesis of enhanced negative feedback in CFS but only in patients with comorbid depression and also in the context of a sample of patients with elevated basal cortisol levels, which is an atypical finding in the literature.

Combined dexamethasone/corticotropin-releasing factor test in chronic fatigue syndrome

BACKGROUND

Studies of hypothalamic-pituitary-adrenal (HPA) axis function in chronic fatigue syndrome (CFS) point to hypofunction, although there are negative reports. Suggested mechanisms include a reduced hypothalamic or supra-hypothalamic stimulus to the HPA axis and enhanced sensitivity to the negative feedback of glucocorticoids. The aim of the current study was to investigate HPA axis function in CFS with the dexamethasone/corticotropin-releasing factor (Dex/CRF) test, in analogy with research in affective disorders.

METHOD

Thirty-four well-characterized female CFS patients and 25 healthy control subjects participated in the low-dose Dex/CRF test. Current major depressive episode was an exclusion criterion. History of early-life stress (ELS) was assessed with the Structured Trauma Interview.

RESULTS

Salivary cortisol responses after 0.5 mg Dex were lower in CFS patients than in controls (before 100 microg CRF, p=0.038; after 100 microg CRF, p=0.015). A secondary analysis revealed an influence of early-life stress and of oestrogen intake. After removal of the 10 participants who were taking an oral oestrogen, patients without a history of ELS showed lower cortisol responses than patients with ELS and controls (before CRF, p=0.005; after CRF, p=0.008).

CONCLUSIONS

CFS is globally associated with reduced cortisol responses in the combined low-dose Dex/CRF test, but this effect is only clearly present in CFS patients without a history of ELS. This study provides further support for an enhanced glucocorticoid negative feedback and/or a reduced central HPA axis drive in CFS. Furthermore, it demonstrates that ELS is an important variable to consider in CFS research.

Possible role for early-life immune insult including developmental immunotoxicity in chronic fatigue syndrome (CFS) or myalgic encephalomyelitis (ME)

Chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME) in some countries, is a debilitating disease with a constellation of multi-system dysfunctions primarily involving the neurological, endocrine and immune systems. While substantial information is available concerning the complex dysfunction-associated symptoms of CFS, environmental origins of the disease have yet to be determined. Part of the dilemma in identifying the cause(s) has been the focus on biomarkers (hormones, neurotransmitters, cytokines, infectious agents) that are contemporary with later-life CFS episodes. Yet, recent investigations on the origins of environmental diseases of the neurological, endocrine, reproductive, respiratory and immune systems suggest that early life toxicologic and other insults are pivotal in producing later-life onset of symptoms. As with autism and childhood asthma, CFS can also occur in children where the causes are certainly early-life events. Immune dysfunction is recognized as part of the CFS phenotype but has received comparatively less attention than aberrant neurological or endocrine function. However, recent research results suggest that early life immune insults (ELII) including developmental immunotoxicity (DIT), which is induced by xenobiotics, may offer an important clue to the origin(s) of CFS. The developing immune system is a sensitive and novel target for environmental insult (xenobiotic, infectious agents, stress) with major ramifications for postnatal health risks. Additionally, many prenatal and early postnatal neurological lesions associated with postnatal neurobehavioral diseases are now recognized as linked to prenatal immune insult and inflammatory dysregulation. This review considers the potential role of ELII including DIT as an early-life component of later-life CFS.

Longitudinal analysis of pro- and anti-inflammatory cytokine production in severely fatigued adolescents

In the adolescent population, fatigue is associated with somatic complaints, unrefreshing sleep, cognitive disturbances and symptoms of depression and anxiety. This pattern of symptoms resembles the one described in chronic fatigue syndrome (CFS). Since immunological alterations have been reported in CFS patients, we wondered whether also severely fatigued girls from a healthy population would show comparable alterations in psychological and immunological parameters. We tested this hypothesis in a longitudinal design, allowing a reliable assessment of the participants' characteristic immune status. Groups of severely fatigued (N=67) and non-fatigued (N=61) participants were selected. Severely fatigued girls reported more depressive symptoms, anxiety, reduced sleep quality, and somatic and CFS-related symptoms than non-fatigued participants across three measurements during one year (T1: spring, T2: autumn, T3: spring). In contrast, no group differences in mitogen-induced cytokine production or T-cell proliferation in vitro or in leukocyte subset counts were observed. Although absolute cytokine production and cell counts were affected by seasonal variation, the within-subject values, relatively to the rest of the participants, were fairly stable. Data from a small group of CFS patients (N=11) showed similarities in self-reported complaints between CFS patients and fatigued participants. Interestingly, CFS patients showed a distinct immune profile when compared to the severely fatigued or non-fatigued participants, i.e. increased levels of anti-inflammatory cytokines (IL-10, decreased IFN-gamma/IL-10 ratio) and reduced levels of pro-inflammatory cytokines (IL-6, TNF-alpha) over all three time points analyzed. These results show that, although overlap in symptomatology between the general population and patients with CFS was observed, only CFS patients show a skewing of the cytokine balance towards an anti-inflammatory profile.

Enhanced feedback sensitivity to prednisolone in chronic fatigue syndrome

OBJECTIVE

Enhancement of negative feedback control of the HPA axis in patients with chronic fatigue syndrome (CFS) has been reported using the low dose dexamethasone suppression test. We have developed the use of prednisolone (5mg) as a more physiologically appropriate alternative to dexamethasone in the investigation of mild degrees of glucocorticoid resistance or supersensitivity. The objective of the study was to use this test to look for alterations in negative feedback control of the HPA axis in CFS patients.

METHODS

Fifteen patients with CFS were recruited after fulfilling strict criteria including the absence of comorbid psychiatric diagnosis. They collected urine between 0900 and 1800h and saliva at 0900h pre-prednisolone. At midnight, they took prednisolone (5mg) orally and then collected urine and saliva at the same intervals the following day.

RESULTS

Salivary cortisol was lower in CFS subjects pre-prednisolone than controls. Urinary cortisol metabolites were lower in CFS subjects pre-prednisolone, but did not reach significance. Both measures were significantly lower in CFS subjects post-dose. Mean percentage suppression of both salivary cortisol and urinary cortisol metabolites was significantly higher in CFS compared to controls.

CONCLUSION

There is enhanced sensitivity of the HPA axis to negative feedback in CFS as demonstrated using the prednisolone suppression test. This provides further evidence of alterations in the control of the HPA axis in patients with established CFS.

Chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is thought to have a worldwide prevalence of 0.4-1% with approximately 240,000 patients in the UK. Diagnosis is based on clinical criteria and critically depends on exclusion of other physical and psychiatric diseases. Studies of pathogenesis have revealed immune system abnormalities and chronic immune activation, dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, brain abnormalities, evidence of emotional stress (comprising host aspects) and evidence of exogenous insults, for example, various microbial infections (Epstein-Barr virus, enteroviruses, parvovirus B19, Coxiella burnetii and Chlamydia pneumoniae), vaccinations and exposure to organophosphate chemicals and other toxins (comprising environmental aspects). Emotional stress appears to be very important as it reduces the ability of the immune system to clear infections, it's presence has been shown to determine whether or not an individual develops symptoms upon virus infection, and it leads to activation of the HPA axis. But, emotional stress is distinct from depression, the presence of which precludes a diagnosis of CFS. There is no specific treatment for CFS other than the much underutilised approach of specific treatment of virus infections. Current priorities are to understand the molecular pathogenesis of disease in terms of human and virus gene expression, to develop a diagnostic test based on protein biomarkers, and to develop specific curative treatments.

Immune and endocrine function in burnout syndrome

OBJECTIVE

Burnout is a stress-induced work-related syndrome. It is associated with a higher incidence of infections possibly pointing to a compromised immune system. In the present study, endocrine and ex vivo immune function of severe cases of burnout were investigated.

METHODS

Endocrine and immune variables were compared in 56 persons with burnout and 38 healthy control subjects. Cortisol after awakening, after a low-dose dexamethasone, and dehydroepiandrosterone-sulphate (DHEAS) were analyzed from saliva. Peripheral blood was analyzed for T, B, and NK cell number and in vitro mitogen-induced pro- and antiinflammatory cytokine release. The capacity of dexamethasone to regulate cytokine release was compared between the groups.

RESULTS

The burnout group showed an increased production of the antiinflammatory cytokine interleukin-10 (IL-10) by monocytes after lipopolysaccharide stimulation. No differences were observed in IL-10 release induced by the T-cell mitogen PHA nor in the proinflammatory cytokines gamma interferon and tumor necrosis factor alpha. The capacity of dexamethasone to regulate cytokine release did not differ between the groups. The number of peripheral blood T cells, B cells, or NK cells was not different either. The burnout group showed higher DHEAS levels but no difference in cortisol levels after awakening or after dexamethasone intake in comparison to controls.

CONCLUSION

Production of the antiinflammatory cytokine IL-10 by monocytes was increased in individuals with burnout syndrome. It seems unlikely that glucocorticoids or changes in glucocorticoid receptor function play a role in this higher IL-10 production.

Long-chain polyunsaturated fatty acids and the pathophysiology of myalgic encephalomyelitis (chronic fatigue syndrome)

Evidence is put forward to suggest that myalgic encephalomyelitis, also known as chronic fatigue syndrome, may be associated with persistent viral infection. In turn, such infections are likely to impair the ability of the body to biosynthesise n-3 and n-6 long-chain polyunsaturated fatty acids by inhibiting the delta-6 desaturation of the precursor essential fatty acids--namely, alpha-linolenic acid and linoleic acid. This would, in turn, impair the proper functioning of cell membranes, including cell signalling, and have an adverse effect on the biosynthesis of eicosanoids from the long-chain polyunsaturated fatty acids dihomo-gamma-linolenic acid, arachidonic acid and eicosapentaenoic acid. These actions might offer an explanation for some of the symptoms and signs of myalgic encephalomyelitis. A potential therapeutic avenue could be offered by bypassing the inhibition of the enzyme delta-6-desaturase by treatment with virgin cold-pressed non-raffinated evening primrose oil, which would supply gamma-linolenic acid and lipophilic pentacyclic triterpenes, and with eicosapentaenoic acid. The gamma-linolenic acid can readily be converted into dihomo-gamma-linolenic acid and thence arachidonic acid, while triterpenes have important free radical scavenging, cyclo-oxygenase and neutrophil elastase inhibitory activities. Furthermore, both arachidonic acid and eicosapentaenoic acid are, at relatively low concentrations, directly virucidal.

Lower serum zinc in Chronic Fatigue Syndrome (CFS): relationships to immune dysfunctions and relevance for the oxidative stress status in CFS

The present study examines serum zinc concentrations in patients with chronic fatigue syndrome (CFS) versus normal volunteers. Serum zinc levels were determined by means of an atomic absorption method. We found that serum zinc was significantly lower in the CFS patients than in the normal controls. There was a trend toward a significant negative correlation between serum zinc and the severity of CFS and there was a significant and negative correlation between serum zinc and the subjective experience of infection. We found that serum zinc was significantly and negatively correlated to the increase in the alpha2 protein fraction and positively correlated to decreases in the expression of mitogen-induced CD69+ (a T cell activation marker) on CD3+ as well as CD3+CD8+ T cells. These results show that CFS is accompanied by a low serum zinc status and that the latter is related to signs of inflammation and defects in early T cell activation pathways. Since zinc is a strong anti-oxidant, the present results further support the findings that CFS is accompanied by increased oxidative stress. The results of these reports suggest that some patients with CFS should be treated with specific antioxidants, including zinc supplements.

Treatment of chronic fatigue syndrome with antibiotics: pilot study assessing the involvement of Coxiella burnetii infection

OBJECTIVE

To examine whether Coxiella burnetii (C. burnetii) is involved in chronic fatigue syndrome (CFS), we administered tetracycline antibiotics to subjects with CFS, and followed changes in clinical symptoms, PCR findings, and C. burnetii antibody titers.

PATIENTS AND METHODS

The subjects were 8 patients with CFS and 213 with nonspecific complaints such as chronic fatigue and low-grade fever for several months or longer but not meeting the diagnostic criteria for CFS. All were examined for C. burnetii infection by nested PCR and the indirect immunofluorescence test (IF).

RESULTS

Four CFS patients (the CFS group) and 54 controls [the post-Q fever fatigue syndrome (QFS) group] positive for C. burnetii were treated mainly with minocycline or doxycycline (100 mg/day) for 3 months. After treatment, all 58 patients tested negative for C. burnetii infection. In the CFS group, no significant difference was noted between the mean pre- and post-treatment temperatures or headache scores. Similarly, there was no significant improvement in performance status (PS) scores. In the QFS group, however, mean temperatures and headache scores were significantly decreased after treatment (p<0.001). PS scores were also improved.

CONCLUSION

These results suggest the possibility of direct involvement of C. burnetii in the pathological state of CFS to be low, despite the C. burnetii infection rate being high in CFS patients. This is a pilot study and further larger investigations are necessary to confirm our preliminary results.

A randomized, double-blind and placebo-controlled study of a Ganoderma lucidum polysaccharide extract in neurasthenia

Ganoderma lucidum has been widely used to treat various diseases, including cancer, diabetes, and neurasthenia in many Asian countries. This randomized, double-blind, placebo-controlled parallel study aimed to investigate the efficacy and safety of a polysaccharide extract of G. lucidum (Ganopoly) in Chinese patients with neurasthenia. One hundred thirty-two patients with neurasthenia according to the diagnosis criteria of the 10th International Classification of Diseases were included in this study. Written consents were obtained from the patients, and the study was conducted in accordance with Good Clinical Practice guidelines. Patients were randomized to receive Ganopoly or placebo orally at 1,800 mg three times a day for 8 weeks. Efficacy assessments comprised the Clinical Global Impression (CGI) improvement of severity scale and the Visual Analogues Scales for the sense of fatigue and well-being. In 123 assessable patients in two treatment groups at the end of the study, Ganopoly treatment for 8 weeks resulted in significantly lower scores after 8 weeks in the CGI severity score and sense of fatigue, with a respective reduction of 15.5% and 28.3% from baseline, whereas the reductions in the placebo group were 4.9% and 20.1%, respectively. The score at day 56 in the sense of well-being increased from baseline to 38.7% in the Ganopoly group compared with 29.7% in the placebo group. The distribution of the five possible outcomes from very much improved to minimally worse was significantly different (X (2) = 10.55; df = 4; P = .0322) after treatment with Ganopoly or placebo. There was a percentage of 51.6% (32 of 62) in the Ganopoly group rated as more than minimally improved compared with 24.6% (15 of 61) in the placebo group (X (2) = 9.51; df = 1; P = .002). Ganopoly was well tolerated in the study patients. These findings indicated that Ganopoly was significantly superior to placebo with respect to the clinical improvement of symptoms in neurasthenia.

Soluble beta-1,3/1,6-glucan from yeast inhibits experimental periodontal disease in Wistar rats

OBJECTIVE

We have investigated whether a purified immunomodulatory water soluble beta-1,3/1,6-glucan isolated from the cell wall of Bakers yeast, Saccharomyces cerevisiae, would influence the progression of ligature-induced periodontal disease, and to modulate accompanying cytokine and hypothalamic-pituitary-adrenal (HPA) axis responses to a lipopolysaccharide (LPS) challenge.

MATERIAL AND METHODS

beta-1,3/1,6-glucan (10 mg/kg/day) was given in the drinking water to Wistar rats during the entire experiment, starting 14 days before disease induction, while control rats were given tap water only. Periodontal disease was assessed when the ligatures had been in place for 35 days.

RESULTS

Orally administered soluble beta-1,3/1,6-glucan significantly reduced periodontal bone loss as measured on digital X-rays (p=0,026). Glucan-treated rats also showed a significantly enhanced plasma level of the HPA axis-driven hormone corticosterone (p=0.047), and of the cytokine transforming growth factor-1beta (p=0.032), as well as a tendency to enhanced IL-10 (p=0.106), induced by intra-peritoneally administered LPS.

CONCLUSION

Soluble beta-1,3/1,6-glucan administered by the oral route diminishes ligature-induced periodontal bone loss in this model. This effect may be attributable to the well documented ability of beta-1,3/1,6-glucan to stimulate macrophage phagocytosis and to skew the T helper (Th)1/Th2 balance towards Th1 and T regulatory responses. The HPA axis may play a significant role in beta-1,3/1,6-glucan induced immune modulation.

2',5'-Oligoadenylate size is critical to protect RNase L against proteolytic cleavage in chronic fatigue syndrome

A dysregulation in the 2',5'-oligoadenylate (2-5A)-dependent RNase L antiviral pathway has been detected in peripheral blood mononuclear cells (PBMC) of chronic fatigue syndrome (CFS) patients, which is characterized by upregulated 2-5A synthetase and RNase L activities, as well as by the presence of a low molecular weight (LMW) 2-5A-binding protein of 37-kDa related to RNase L. This truncated protein has been shown to originate from proteolytic cleavage of the native 83-kDa RNase L by m-calpain and human leukocyte elastase (HLE). We investigated the possible role of 2-5A oligomers in the proteolytic action toward the endonuclease and show that incubation of CFS PBMC extracts with 2-5A trimer and tetramer, but not with the dimer, results in a significant protection of the native 83-kDa RNase L against cleavage by endogenous and purified proteases. Similar results are obtained with a purified recombinant RNase L. An analysis of the size of 2-5A oligomers produced by the catalytic activity of the 2-5A synthetase present in PBMC extracts further shows that samples containing the 37-kDa RNase L preferentially produce 2-5A dimers instead of higher oligomers. Taken together, our results indicate that homodimerization of RNase L by 2-5A oligomers higher than the dimer prevents its cleavage by proteolytic enzymes. The presence of the truncated 37-kDa RNase L in PBMC extracts is therefore likely to result, not only from the abnormal activation of inflammatory proteases, but also from a dysregulation in 2-5A synthetase induction or activation towards the preferential production of 2-5A dimers.

Stress-induced changes in LPS-induced pro-inflammatory cytokine production in chronic fatigue syndrome

OBJECTIVE

It has been suggested that a hypofunctional hypothalamic-pituitary-adrenal (HPA) axis in chronic fatigue syndrome could result in an exaggerated release of pro-inflammatory cytokines during stress. As pro-inflammatory cytokines are involved in the induction of sickness behavior and thus constitute a potential physiological correlate of stress-induced symptom exacerbation in chronic fatigue syndrome, we set out to evaluate the LPS-induced production of pro-inflammatory cytokines during psychosocial stress in CFS and healthy controls.

METHOD

Twenty-one CFS patients and 20 healthy controls matched for age and gender underwent a standardized psychosocial stress test (Trier social stress test, TSST). Adrenocorticotropine hormone (ACTH), salivary cortisol and plasma cortisol levels were measured before and repeatedly following exposure to the stressor. Lipopolysaccharide-stimulated production of interleukin-6 and tumor necrosis factor-alpha were assessed at baseline as well as 10 and 60 min after the stress test.

RESULTS

CFS patients showed an inverse stress-induced response pattern of LPS-stimulated cytokines responses in comparison to healthy controls, i.e. stimulated cytokine production decreased shortly after stress in CFS patients, while it increased in controls. Fatigue scores and basal LPS-induced cytokine levels were significantly associated for TNF-alpha in controls and for both cytokines in CFS patients. Stress-induced changes in stimulated cytokine production were not associated with general fatigue scores in the control group, whereas in the CFS group, fatigue scores were significantly correlated with integrated levels of LPS-induced cytokines. However, partial correlations revealed that these results were due to the high correlations with basal LPS-induced cytokine levels.

CONCLUSION

CFS patients do not show an exaggerated secretion of LPS-induced cytokines. Although cortisol responses to stress were normal, pro-inflammatory cytokine levels in CFS patients were significantly attenuated. Possible intracellular mechanisms, such as for example an enhanced sensitivity to inhibitory effects of glucocorticoids, a diminished responsivity to catecholaminergic stimulation, and a disruption of intracellular activation are discussed. Basal levels of stimulated pro-inflammatory Il-6 levels are generally related to fatigue scores. However, in CFS patients this association is of greater magnitude and can also be observed for TNF-alpha.

Effect of bojungikki-tang on lipopolysaccharide-induced cytokine production from peripheral blood mononuclear cells of chronic fatigue syndrome patients

Bojungikki-tang (BIT) has been widely used to treat patients suffering from chronic fatigue syndrome (CFS). However, its effect has not been yet investigated experimentally. Based upon the clinical presentation of CFS, we hypothesized that cytokines may play a role in the pathogenesis of the disease. We studied the effect of BIT on lipopolysaccharide (LPS)-induced various cytokines production in peripheral blood mononuclear cells (PBMC) of CFS patients. Bojungikki-tang (1 mg/mL) significantly inhibited LPS-induced tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-10, transforming growth factor (TGF)-beta1 production by 63.55% +/- 0.19%, 55.06% +/- 0.27%, 48.23% +/- 0.48%, 54.09% +/- 0.76%, respectively (P < 0.05). Bojungikki-tang showed a slightly lower inhibitory effect of LPS-induced Interferon (IFN)-gamma production. These results suggest that BIT may be useful in treating fatigue associated with chronic diseases.

High levels of type 2 cytokine-producing cells in chronic fatigue syndrome

The aetiology of chronic fatigue syndrome (CFS) is not known. However, it has been suggested that CFS may be associated with underlying immune activation resulting in a Th2-type response. We measured intracellular production of interferon (IFN)-gamma and interleukin (IL)-2; type 1 cytokines), IL-4 (type 2) and IL-10 (regulatory) by both polyclonally stimulated and non-stimulated CD4 and CD8 lymphocytes from patients with CFS and control subjects by flow cytometry. After polyclonal activation we found evidence of a significant bias towards Th2- and Tc2-type immune responses in CFS compared to controls. In contrast, levels of IFN-gamma, IL-2 and IL-10-producing cells were similar in both study groups. Non-stimulated cultures revealed significantly higher levels of T cells producing IFN-gamma or IL-4 in CFS patients. Concluding, we show evidence for an effector memory cell bias towards type 2 responsiveness in patients with CFS, as well as ongoing type 0 immune activation in unstimulated cultures of peripheral blood cells.

Effect of Kuibitang on lipopolysaccharide-induced cytokine production in peripheral blood mononuclear cells of chronic fatigue syndrome patients

Kuibitang (KBT) is clinically used to treat patients suffering from chronic fatigue syndrome (CFS) in South Korea. However, its effect has not been investigated experimentally. Recent reports have shown that CFS patients display an altered cytokine production. We examined the effect of KBT on lipopolysaccharide (LPS)-induced various cytokines production in peripheral blood mononuclear cells (PBMC) of CFS patients and healthy controls. KBT (1 mg/ml) significantly inhibited LPS-induced tumor necrosis factor-alpha, interleukin-10, and transforming growth factor-beta1 production in PBMC of CFS patients. However, LPS-induced interferon-gamma production was significantly increased by KBT (0.01 mg/ml). These results provide evidence of a novel activity of the KBT that regulate cytokines production related with CFS.

Glucocorticoids and glucocorticoid receptors: mediators of fatigue?

Fatigue is a common problem; when chronic and disabling, subjects can be categorized as having chronic fatigue syndrome (CFS). Whilst it is most likely a multifactorial condition of biopsychosocial origin, the nature of the pathophysiological component remains unclear. There has been a wealth of interest in the possible hypothalamo-pituitary-adrenal (HPA) axis dysfunction in CFS, and whether such changes may mediate fatigue. On balance, there appears to be reduced cortisol output in a proportion of patients, together with heightened negative feedback and glucocorticoid receptor function. There is evidence for impaired adrenocorticotropic hormone (ACTH) and cortisol responses to a variety of challenges. However, there is no evidence for a specific or uniform dysfunction of the HPA axis. Evidence that these changes may be related to symptom production comes from randomized controlled trials of glucocorticoid replacement therapy, which have shown improvements in fatigue and disability. Given the many factors that may impinge on the HPA axis in CFS, such as inactivity, sleep disturbance, psychiatric comorbidity, medication and ongoing stress, it seems likely that there is not a single or specific change to the HPA axis in CFS and that the observed HPA axis disturbances are of multifactorial etiology. This is further supported by a comparison of neuroendocrine findings in other conditions in which fatigue is prominent, showing both similarities and differences with the pattern in CFS.

A systematic review and critical evaluation of the immunology of chronic fatigue syndrome

OBJECTIVE

Immune dysfunction in patients with chronic fatigue syndrome (CFS) has been widely but inconsistently reported. Traditional reviews of the literature have produced a variety of conclusions. We present the results of the first systematic review of the subject.

METHODS

EMBASE, MEDLINE and PSYCHINFO databases were searched, and leading researchers in the field were contacted. Inclusion criteria were applied, and studies were then divided into groups based on the quality of their methodology. Study results were collated and described.

RESULTS

Studies ranged widely in quality. There was an inverse association between study quality and finding low levels of natural killer cells, suggesting that the association may be related to study methodology. On the other hand, reports of abnormalities in T cells and cytokine levels were not related to study quality.

CONCLUSIONS

The conclusions of this systematic review differ from a recent traditional narrative review of the immunology of CFS. No consistent pattern of immunological abnormalities is identified.

Atypical depression spectrum disorder - neurobiology and treatment

Depressive syndromes are a group of heterogeneous disorders. Atypical depression (AD) with reversed vegetative signs, such as hyperphagia or hypersomnia, is traditionally neglected, demonstrated by the fact that in the most widely used depression scales, such as the Hamilton Depression Scale (HAMD), melancholic symptoms have a specific weight, while, by contrast, reversed vegetative signs are not included. However, epidemiologically and phenomenologically related disorders to AD do exist, such as somatoform disorders, neurasthenia (chronic fatigue syndrome) and fibromyalgia (FM). In this spectrum, here called the AD spectrum, instead a decrease in hypothalamus-pituitary-adrenocortical (HPA) axis activity seems to exist. This has similarities to Cushing's disease, where a suppression of central HPA system activity is accompanied by features of AD and somatization in a considerable number of patients. Opposite vegetative features might therefore be related to the opposite dysregulation of the HPA system. The psychopharmacological intervention in the AD spectrum should therefore differ from that used in typical major depression. MAO inhibitors, low-dose tricyclic antidepressants and 5-HT3 antagonists demonstrated therapeutic efficacy, but the existing studies focused on different aspects. Hypericum extracts might be an alternative pharmacological intervention, which demonstrated therapeutic efficacy in the symptom range of the spectrum.

Enhanced glucocorticoid sensitivity in patients with chronic fatigue syndrome

OBJECTIVE

Alterations of the immune-neuroendocrine interplay have been described in chronic fatigue syndrome (CFS). Employing a recently developed method, the study set out to investigate whether patients with CFS have an altered sensitivity to glucocorticoids (GCs) when under stress.

METHODS

A total of 21 CFS patients and 20 healthy age- and gender-matched controls underwent a standardized psychosocial stress test (Trier Social Stress Test, TSST). Salivary and plasma cortisol levels were measured repeatedly following exposure to the stressor. GC sensitivity was assessed in vitro by dexamethasone inhibition of lipopolysaccharide-stimulated production of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNC-α).

RESULTS

Cortisol responses following the TSST did not differ significantly between CFS patients and healthy controls. GC sensitivity differed significantly between CFS patients and healthy controls, with CFS patients showing a greater sensitivity towards GCs (TNF-α: F 1/39 = 7.32, P = 0.01; IL-6: F 1/39 = 9.73, P = 0.004).

CONCLUSION

Consistent with recent evidence, CFS patients are characterized by an enhanced sensitivity to glucocorticoids. The implications for secondary processes, such as the regulatory influence of glucocorticoids on immune processes, are discussed.

Impact of oral contraceptive use on glucocorticoid sensitivity of pro-inflammatory cytokine production after psychosocial stress

We previously reported that women using oral contraceptives (OC) show blunted free cortisol responses to psychosocial stress compared to medication-free women. Low cortisol responses to stress have been shown to be associated with increased susceptibilities to chronic inflammatory and autoimmune processes in animal models and certain human diseases.To address the question if the blunted free cortisol response of OC users may be compensated at the level of the target tissue, we measured hypothalamus-pituitary-adrenal (HPA) axis activation and glucocorticoid (GC) sensitivity of pro-inflammatory cytokine production after psychosocial stress in 14 women using OC and 11 women in the luteal phase of the menstrual cycle. All subjects were exposed to the psychosocial stress paradigm 'Trier Social Stress Test' (TSST). Free cortisol was measured repeatedly before and after stress. GC sensitivity was assessed by dexamethasone (DEX) inhibition of lipopolysaccharide (LPS) stimulated production of interleukin-6 (IL-6) in whole blood, immediately before, as well as 10 and 60 min after the stress test. As expected, the stress test induced significant increases in free cortisol in luteal phase women, while OC users showed blunted responses (F=3.31;p<0.05). GC sensitivity showed different response patterns; In luteal phase women a slight but not significant decrease was observed throughout the experiment. In contrast, women using OC showed a significant increase in GC sensitivity after stress (F=3.559;p<0.05). These results show, that an increase in GC sensitivity of pro-inflammatory cytokine production may at least in part compensate the low cortisol levels seen in OC users after stress. This could be one mechanism to protect women using OC medication from chronic inflammatory and autoimmune diseases.

The neuroendocrinology of chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is a common and disabling problem; although most likely of biopsychosocial origin, the nature of the pathophysiological components remains unclear. There has been a wealth of interest in the endocrinology of this condition, which will be reviewed in this article. Most studied has been the hypothalamic-pituitary-adrenal (HPA) axis; although the quality of many studies is poor, the overall balance of evidence points to reduced cortisol output in at least some patients, with some evidence that this is linked to symptom production or persistence. There is evidence for heightened negative feedback and glucocorticoid receptor function and for impaired ACTH and cortisol responses to a variety of challenges. However, there is no evidence for a specific or uniform dysfunction of the HPA axis. Given the many factors that may impinge on the HPA axis in CFS, such as inactivity, sleep disturbance, psychiatric comorbidity, medication, and ongoing stress, it seems likely that HPA axis disturbance is heterogeneous and of multifactorial etiology in CFS. Studies assessing GH, dehydroepiandrostenedione and its sulfate, melatonin, leptin, and neuroendocrine-monoamine interactions are also reviewed. There is some evidence from these studies to suggest alterations of dehydroepiandrostenedione sulfate function and abnormal serotonin function in CFS, but whether these changes are of functional importance remains unclear. To obtain a clearer assessment of the etiological and pathophysiological relevance of endocrine changes in CFS, it is suggested that more prospective cohort studies be undertaken in groups at high risk for CFS, that patients with CFS are followed up into recovery, and that multidimensional assessments are undertaken to unravel the influence of the various confounding factors on the observed endocrine changes in CFS.

Treatment with SRL172 (heat-killed Mycobacterium vaccae) inhibits progression of established experimental periodontal disease in Wistar rats

Periodontal disease is accompanied by a change in the periodontal bacterial flora, and an increase in Th2 cytokine expression. Therefore, preparations that can down-regulate Th2 responses and increase Th1 responses to bacteria may have therapeutic effects. SRL172, a preparation of heat-killed Mycobacterium vaccae (NCTC11659), has been shown to have these properties in man and animals and, in a previous study, a single subcutaneous injection of this material 13 days before application of ligatures to the right second molars of Wistar rats strikingly reduced subsequent destruction of the tooth-supporting tissues. The same material has therefore been tested in a therapeutic protocol, in rats with ongoing periodontal disease. A silk ligature was placed round the maxillary right second molar in the gingival sulcus on day 0. This was removed after two weeks, and the animals immediately received 0.1 mg SRL172 s.c. or saline. One week later (i.e. at three weeks), a boost of 1.0 mg SRL172 or saline was given. Animals were sacrificed at eight weeks (i.e. five weeks after the booster dose). Treatment of ongoing periodontal disease with SRL172 significantly reduced fibre loss (p = 0.046 by histometry) and bone loss (p = 0.0008 by radiography) on the ligatured side, and reduced fibre loss (p = 0.0086) on the control side. Thus SRL172 is an effective treatment in this model. As SRL172 has undergone extensive safety testing in man, these results justify clinical studies in periodontal disease, and such studies are now planned.

Cytokine and other immunologic markers in chronic fatigue syndrome and their relation to neuropsychological factors

The literature is reviewed and data are presented that relate to a model we have developed to account for the perpetuation of the perplexing disorder currently termed chronic fatigue syndrome (CFS). In patients with CFS there is chronic lymphocyte overactivation with cytokine abnormalities that include perturbations in plasma levels of proinflammatory cytokines and decrease in the ratio of Type 1 to Type 2 cytokines produced by lymphocytes in vitro following mitogen stimulation. The initiation of the syndrome is frequently sudden and often follows an acute viral illness. Our model for the subsequent chronicity of this disorder holds that the interaction of psychological factors (distress associated with either CFS-related symptoms or other stressful life events) and the immunologic dysfunction contribute to (a) CFS-related physical symptoms (e.g., perception of fatigue and cognitive difficulties, fever, muscle and joint pain) and increases in illness burden and (b) impaired immune surveillance associated with cytotoxic lymphocytes with resulting activation of latent herpes viruses.

LPS-induced IL-10 production in whole blood cultures from chronic fatigue syndrome patients is increased but supersensitive to inhibition by dexamethasone

Several causes have been held responsible for the chronic fatigue syndrome (CFS), including an altered hypothalamus-pituitary-adrenal gland (HPA)-axis activity, viral infections and a reduced Th1 activity. Therefore, it was investigated whether the regulation of IL-10 is different in CFS. LPS-induced cytokine secretion in whole blood cultures showed a significant increase in IL-10 and a trend towards a decrease in IL-12 as compared with healthy controls. In patients and controls, IL-12 secretion was equally sensitive to suppression by dexamethasone, whereas IL-10 secretion appeared more sensitive in CFS-patients. In controls, IL-10 and IL-12 secretion were inversely correlated with free serum cortisol (r=-0.492, p<0.02 and r=-0.434, p<0.05, respectively). In CFS, such an inverse correlation was found for IL-12 (r=-0.611, p<0.02) but not for IL-10 (r=-0.341, ns). These data are suggestive for a disturbed glucocorticoid regulation of IL-10 in CFS.

Plasma leptin in chronic fatigue syndrome and a placebo-controlled study of the effects of low-dose hydrocortisone on leptin secretion

OBJECTIVE

Previous studies have suggested that chronic fatigue syndrome (CFS) is associated with changes in appetite and weight, and also with mild hypocortisolism. Because both of these features may be related to leptin metabolism, we undertook a study of leptin in CFS.

DESIGN

(i) A comparison of morning leptin concentration in patients with CFS and controls and (ii) a randomized, placebo-controlled crossover study of the effects of hydrocortisone on leptin levels in CFS.

PATIENTS

Thirty-two medication free patients with CFS but not comorbid depression or anxiety. Thirty-two age, gender, weight, body mass index and menstrual cycle matched volunteer subjects acted as controls.

MEASUREMENTS

We measured basal 0900 h plasma leptin levels in patients and controls. All 32 patients were taking part in a randomized, placebo-controlled crossover trial of low dose (5 or 10 mg) hydrocortisone as a potential therapy for CFS. We measured plasma leptin after 28 days treatment with hydrocortisone and after 28 days treatment with placebo.

RESULTS

At baseline, there was no significant difference in plasma leptin between patients [mean 13.8, median 7.4, interquartile range (IQR) 18.0 ng/ml] and controls (mean 10.2, median 5.5, IQR 11.3 ng/ml). Hydrocortisone treatment, for both doses combined, caused a significant increase in leptin levels compared to placebo. When the two doses were analysed separately, only 10 mg was associated with a significant effect on leptin levels. We also compared the hydrocortisone induced increase in leptin between those who were deemed treatment-responders and those deemed nonresponders. Responders showed a significantly greater hydrocortisone-induced rise in leptin than nonresponders. This association between a clinical response to hydrocortisone and a greater rise in leptin levels may indicate a greater biological effect of hydrocortisone in these subjects, perhaps due to increased glucocorticoid receptor sensitivity, which may be present in some patients with CFS.

CONCLUSIONS

We conclude that, while we found no evidence of alterations in leptin levels in CFS, low dose hydrocortisone therapy caused increases in plasma leptin levels, with this biological response being more marked in those CFS subjects who showed a positive therapeutic response to hydrocortisone therapy. Increases in plasma leptin levels following low dose hydrocortisone therapy may be a marker of pretreatment physiological hypocortisolism and of response to therapy.

Altered glucocorticoid regulation of the immune response in the chronic fatigue syndrome

It is increasingly recognized that glucocortiocoids (GCs) can have subtle modulatory effects in immunoregulation rather than having generalized immunosuppressive effects. GCs suppress Th1 cells and cellular immunity, but may favor Th2 responses and humoral immunity. The chronic fatigue syndrome (CFS) appears to be associated with a disturbed HPA-axis. Moreover, CFS patients show several immunological changes suggestive of decreased cellular immunity. It is postulated herein that in CFS patients a decreased Th1/Th2 balance may be the result of selective effects of GC on the IL-10/IL-12 regulatory circuit.