Glucocorticoid sensitivity in fibromyalgia patients: decreased expression of corticosteroid receptors and glucocorticoid-induced leucine zipper

A two-component model of hair cortisol concentration in fibromyalgia: Independent effects of pain chronicity and severity

BACKGROUND

Fibromyalgia (FM) is a chronic pain disorder of unknown aetiopathogenesis, in which the role of activity of the hypothalamic-pituitary-adrenal (HPA) axis is not clearly established.

METHODS

This study analysed the modulatory effects of disease chronicity and severity on cortisol levels. Hair cortisol concentrations (HCC) and clinical evaluation data (pain severity, impact of FM on daily activities, depression, anxiety, fatigue and insomnia) were collected from 47 female patients with FM and 36 healthy women (HW).

RESULTS

The results showed that disease chronicity, with a negative effect, and symptom severity, with a positive effect, were independent predictors of HCC. Patients with a shorter disease duration had higher HCC than patients with a longer disease duration and healthy participants. Furthermore, patients with greater symptom severity had higher HCC than those patients with lower clinical severity and healthy participants. While disease chronicity in FM was associated with a decrease in HCC, clinical severity increased HCC.

CONCLUSIONS

These results support the existence of a dysfunction in the regulation of the HPA axis in FM and its possible contribution to chronic pain development.

SIGNIFICANCE

This is the first study to assess hair cortisol concentrations in a specific sample of patients with fibromyalgia (FM). This method is especially useful for the assessment of long-term regular cortisol excretion. Results showed a two-component model for explaining cortisol levels: disease chronicity, with a negative effect, and symptom severity, with a positive effect. This suggests that severe pain/stress evokes higher cortisol levels at earlier stages of FM, while in the longer term a decrease in cortisol levels was observed.

Stress biomarkers in individuals with fibromyalgia syndrome: a systematic review with meta-analysis

ABSTRACT

Evidence suggests an involvement of hypothalamic-pituitary-adrenal (HPA) axis dysregulation in the development and maintenance of fibromyalgia syndrome (FMS). However, studies on the stress response via the HPA-axis in individuals with FMS show conflicting results. To better understand the relationship between FMS and HPA-axis dysregulation, we (1) systematically summarized the current level of evidence on HPA biomarkers in individuals with FMS compared with individuals without and (2) evaluated whether FMS is associated with a specific pattern of HPA dysregulation. The main outcome measures were cortisol, adrenocorticotropic hormone (ACTH), corticotropin-releasing hormone (CRH), epinephrine, and norepinephrine. A systematic search of MEDLINE, EMBASE, and PsychMed yielded 47 studies eligible for meta-analysis, including 1465 individuals with FMS and 1192 FMS-free controls. No main effect of FMS was found on altered levels of blood cortisol, ACTH, CRH, and epinephrine. Compared with controls, salivary and urinary cortisol levels were decreased in individuals with FMS, whereas blood levels of norepinephrine were increased. However, heterogeneity of data was high with significant evidence for publication bias. Overall, the data are compatible with association of FMS with adrenocortical hypofunction in the presence of increased sympathetic tone. However, the data are partially contradictory, so it must be assumed that the data are highly dependent on the respective study designs, patient samples, and analytical methods and do not necessarily demonstrate an abnormal HPA-axis function in FMS.

Unbiased immune profiling reveals a natural killer cell-peripheral nerve axis in fibromyalgia

ABSTRACT

The pathophysiology of fibromyalgia syndrome (FMS) remains elusive, leading to a lack of objective diagnostic criteria and targeted treatment. We globally evaluated immune system changes in FMS by conducting multiparametric flow cytometry analyses of peripheral blood mononuclear cells and identified a natural killer (NK) cell decrease in patients with FMS. Circulating NK cells in FMS were exhausted yet activated, evidenced by lower surface expression of CD16, CD96, and CD226 and more CD107a and TIGIT. These NK cells were hyperresponsive, with increased CCL4 production and expression of CD107a when co-cultured with human leukocyte antigen null target cells. Genetic and transcriptomic pathway analyses identified significant enrichment of cell activation pathways in FMS driven by NK cells. Skin biopsies showed increased expression of NK activation ligand, unique long 16-binding protein, on subepidermal nerves of patients FMS and the presence of NK cells near peripheral nerves. Collectively, our results suggest that chronic activation and redistribution of circulating NK cells to the peripheral nerves contribute to the immunopathology associated with FMS.

Glucocorticoid Therapy in Inflammatory Bowel Disease: Mechanisms and Clinical Practice

Inflammatory bowel disease (IBD) comprises ulcerative colitis (UC) and Crohn's disease (CD). IBD etiopathology is multifactorial and involves alteration of immune cells and chronic activation of the inflammatory cascade against yet unknown environmental factors that trigger the disease. IBD therapy aims at improving the quality of life and reducing the risk of disease-related complications to avoid the need for surgery. There is no specific cure for IBDs, and the focus of therapy is supportive measures and use of anti-inflammatory and immunosuppressive drugs. Glucocorticoids (GCs) are powerful anti-inflammatory and immunomodulatory agents used to treat many acute and chronic inflammatory diseases. GCs remain basic treatment for moderate-to-severe IBD, but their use is limited by several important adverse drug effects. Topical administration of a second-generation of GCs, such as budesonide and beclomethasone dipropionate (BDP), represents a valid alternative to use of older, systemic GCs. Administration of second-generation GCs shows promisingly high topical activity and less systemic toxicity, but maintenance therapy with these new GCs in IBD patients is associated with multiple adverse effects. In this review, we make a comparative analysis of the efficacy of first-generation and second-generation GCs in IBD treatment. Unraveling GC biology at the molecular level to uncouple their clinical benefits from detrimental effects is important. One approach is to consider new GC mediators, such as glucocorticoid-induced leucine zipper, which may have similar anti-inflammatory properties, but avoids the side effects of GCs. This in-depth analysis can help to improve the development and the clinical outcomes of GC therapies in IBD.

Glucocorticoid-Induced Leucine Zipper as a Druggable Target in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders with a complex pathogenesis, affecting people of all ages. They are characterized by alternating phases of clinical relapse and remission, depending on the fine balance between immune cells and the gut microbiota. The cross talk between cells of the immune system and the gut microbiota can result in either tolerance or inflammation, according to multifactorial triggers, ranging from environmental factors to genetic susceptibility. Glucocorticoid (GC) administration remains the first-line treatment for IBDs, although long-term use is limited by development of serious adverse effects. Recently, new alternative pharmacological therapies have been developed, although these are not always effective in IBD patients. There is a constant demand for effective new drug targets to guarantee total remission and improve the quality of life for IBD patients. The glucocorticoid-induced leucine zipper (GILZ) has been implicated as a promising candidate for this purpose, in view of its powerful anti-inflammatory effects that mimic those of GCs while avoiding their unwanted adverse reactions. Here we present and discuss the latest findings about the involvement of GILZ in IBDs.

Could epigenetics help explain racial disparities in chronic pain?

African Americans disproportionately suffer more severe and debilitating morbidity from chronic pain than do non-Hispanic Whites. These differences may arise from differential exposure to psychosocial and environmental factors such as adverse childhood experiences, racial discrimination, low socioeconomic status, and depression, all of which have been associated with chronic stress and chronic pain. Race, as a social construct, makes it such that African Americans are more likely to experience different early life conditions, which may induce epigenetic changes that sustain racial differences in chronic pain. Epigenetics is one mechanism by which environmental factors such as childhood stress, racial discrimination, economic hardship, and depression can affect gene expression without altering the underlying genetic sequence. This article provides a narrative review of the literature on epigenetics as a mechanism by which differential environmental exposure could explain racial differences in chronic pain. Most studies of epigenetic changes in chronic pain examine DNA methylation. DNA methylation is altered in the glucocorticoid (stress response) receptor gene, NR3C1, which has been associated with depression, childhood stress, low socioeconomic status, and chronic pain. Similarly, DNA methylation patterns of immune cytokine genes have been associated with chronic stress states. Thus, DNA methylation changes may play an essential role in the epigenetic modulation of chronic pain in different races with a higher incidence of epigenetic alterations contributing to more severe and disabling chronic pain in African Americans.

Neuroplasticity of Supraspinal Structures Associated with Pathological Pain

Peripheral nerve and spinal cord injuries, along with other painful syndromes such as fibromyalgia, diabetic neuropathy, chemotherapeutic neuropathy, trigeminal neuralgia, complex regional pain syndrome, and/or irritable bowel syndrome, cause several neuroplasticity changes in the nervous system along its entire axis affecting the different neuronal nuclei. This paper reviews these changes, focusing on the supraspinal structures that are involved in the modulation and processing of pain, including the periaqueductal gray matter, red nucleus, locus coeruleus, rostral ventromedial medulla, thalamus, hypothalamus, basal ganglia, cerebellum, habenula, primary, and secondary somatosensory cortex, motor cortex, mammillary bodies, hippocampus, septum, amygdala, cingulated, and prefrontal cortex. Hyperexcitability caused by the modification of postsynaptic receptor expression, central sensitization, and potentiation of presynaptic delivery of neurotransmitters, as well as the reduction of inhibitory inputs, changes in dendritic spine, neural circuit remodeling, alteration of gray matter, and upregulation of proinflammatory mediators (e.g., cytokines) by reactivation of astrocytes and microglial cells are the main functional, structural, and molecular neuroplasticity changes observed in the above supraspinal structures, associated with pathological pain. Studying these changes in greater depth may lead to the implementation and improvement of new therapeutic strategies against pathological pain. Anat Rec, 300:1481-1501, 2017. © 2017 Wiley Periodicals, Inc.

The Role of Stress Regulation on Neural Plasticity in Pain Chronification

Pain, especially chronic pain, is one of the most common clinical symptoms and has been considered as a worldwide healthcare problem. The transition from acute to chronic pain is accompanied by a chain of alterations in physiology, pathology, and psychology. Increasing clinical studies and complementary animal models have elucidated effects of stress regulation on the pain chronification via investigating activations of the hypothalamic-pituitary-adrenal (HPA) axis and changes in some crucial brain regions, including the amygdala, prefrontal cortex, and hippocampus. Although individuals suffer from acute pain benefit from such physiological alterations, chronic pain is commonly associated with maladaptive responses, like the HPA dysfunction and abnormal brain plasticity. However, the causal relationship among pain chronification, stress regulation, and brain alterations is rarely discussed. To call for more attention on this issue, we review recent findings obtained from clinical populations and animal models, propose an integrated stress model of pain chronification based on the existing models in perspectives of environmental influences and genetic predispositions, and discuss the significance of investigating the role of stress regulation on brain alteration in pain chronification for various clinical applications.

Potential drug therapies for the treatment of fibromyalgia

INTRODUCTION

Fibromyalgia (FM) is a common, complex chronic widespread pain condition is characterized by fatigue, sleep disturbance and cognitive dysfunction. Treatment of FM is difficult, requiring both pharmacological and non-pharmacological approaches, with an empiric approach to drug therapy focused toward individual symptoms, particularly pain. The effectiveness of current medications is limited with many patients discontinuing use.

AREAS COVERED

A systemic database search has identified 26 molecular entities as potential emerging drug therapies. Advances in the understanding of the pathophysiology of FM provides clues to targets for new medications. Investigation of bioamine modulation and α2δ ligands and novel targets such as dopamine receptors, NMDA receptors, cannabinoid receptors, melatonin receptors and potassium channels has identified potential drug therapies.

EXPERT OPINION

Modest improvement of health status in patients with FM has been observed with drugs targeting a diverse range of molecular mechanisms. No single drug, however, offered substantial efficacy against all the symptoms characteristic of FM. Identification of new and improved therapies for FM needs to address the heterogeneity of the condition, which suggests existence of patient subgroups, the relationship of central and peripheral aspects of the pathophysiology and a requirement of combination therapy with drugs targeting multiple molecular mechanisms.

Fibromyalgia: A Critical and Comprehensive Review

Fibromyalgia is a disorder that is part of a spectrum of syndromes that lack precise classification. It is often considered as part of the global overview of functional somatic syndromes that are otherwise medically unexplained or part of a somatization disorder. Patients with fibromyalgia share symptoms with other functional somatic problems, including issues of myalgias, arthralgias, fatigue and sleep disturbances. Indeed, there is often diagnostic and classification overlap for the case definitions of a variety of somatization disorders. Fibromyalgia, however, is a critically important syndrome for physicians and scientists to be aware of. Patients should be taken very seriously and provided optimal care. Although inflammatory, infectious, and autoimmune disorders have all been ascribed to be etiological events in the development of fibromyalgia, there is very little data to support such a thesis. Many of these disorders are associated with depression and anxiety and may even be part of what has been sometimes called affected spectrum disorders. There is no evidence that physical trauma, i.e., automobile accidents, is associated with the development or exacerbation of fibromyalgia. Treatment should be placed on education, patient support, physical therapy, nutrition, and exercise, including the use of drugs that are approved for the treatment of fibromyalgia. Treatment should not include opiates and patients should not become poly pharmacies in which the treatment itself can lead to significant morbidities. Patients with fibromyalgia are living and not dying of this disorder and positive outlooks and family support are key elements in the management of patients.

The effect of sex and irritable bowel syndrome on HPA axis response and peripheral glucocorticoid receptor expression

BACKGROUND AND AIMS

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been reported in irritable bowel syndrome (IBS). Enhanced HPA axis response has been associated with reduced glucocorticoid receptor (GR) mediated negative feedback inhibition. We aimed to study the effects of IBS status, sex, or presence of early adverse life events (EAL) on the cortisol response to corticotropin-releasing factor (CRF) and adrenocorticotropic hormone (ACTH), and on GR mRNA expression in peripheral blood mononuclear cells (PBMCs).

METHODS

Rome III+ IBS patients and healthy controls underwent CRF (1μg/kg ovine) and ACTH (250μg) stimulation tests with serial plasma ACTH and cortisol levels measured (n=116). GR mRNA levels were measured using quantitative PCR (n=143). Area under the curve (AUC) and linear mixed effects models were used to compare ACTH and cortisol response measured across time between groups.

RESULTS

There were divergent effects of IBS on the cortisol response to ACTH by sex. In men, IBS was associated with an increased AUC (p=0.009), but in women AUC was blunted in IBS (p=0.006). Men also had reduced GR mRNA expression (p=0.007). Cumulative exposure to EALs was associated with an increased HPA response. Lower GR mRNA was associated with increased pituitary HPA response and increased severity of overall symptoms and abdominal pain in IBS.

CONCLUSION

This study highlights the importance of considering sex in studies of IBS and the stress response in general. Our findings also provide support for PBMC GR mRNA expression as a peripheral marker of central HPA response.

The cardiovascular and hypothalamus-pituitary-adrenal axis response to stress is controlled by glucocorticoid receptor sequence variants and promoter methylation

BACKGROUND

Gender, genetic makeup, and prior experience interact to determine physiological responses to an external perceived stressor. Here, we investigated the contribution of both genetic variants and promoter methylation of the NR3C1 (glucocorticoid receptor) gene to the cardiovascular and hypothalamus-pituitary-adrenal (HPA) axis response to the socially evaluated cold pressor test (seCPT).

RESULTS

Two hundred thirty-two healthy participants were recruited and underwent the experiment. They were randomly assigned to either the seCPT group (cold water) or a control group (warm water). The seCPT group had a clear stress reaction; salivary cortisol levels and peak systolic and diastolic blood pressure all increased significantly compared to the control group. GR genotype (TthIIII, NR3C1-I, 1H, E22E, R23K, BclI and 9beta) and methylation data were obtained from 218 participants. Haplotypes were built from the GR genotypes, and haplotype 2 (minor allele of BclI) carriers had a higher cortisol response to the seCPT in comparison to non-carriers (20.77 ± 13.22; 14.99 ± 8.42; p = 0.034), as well as independently of the experimental manipulation, higher baseline heart rate (72.44 ± 10.99; 68.74 ± 9.79; p = 0.022) and blood pressure (115.81 ± 10.47; 111.61 ± 10.74; p = 0.048). Average methylation levels throughout promoter 1F and 1H were low (2.76 and 1.69 %, respectively), but there was a strong correlation between individual CpGs and the distance separating them (Pearson's correlation r = 0.725, p = 3.03 × 10(-26)). Higher promoter-wide methylation levels were associated with decreased baseline blood pressure, and when incorporated into a linear mixed effect model significantly predicted lower systolic and diastolic blood pressure evolution over time in response to the experimental manipulation. The underlying genotype significantly predicted methylation levels; particularly, the homozygous BclI minor allele was associated with higher methylation in promoter 1H (p = 0.042).

CONCLUSIONS

This is one of the first studies linking epigenetic modifications of the GR promoter, receptor genotype and physiological measures of the stress response. At baseline, there were clear genetic and epigenetic effects on blood pressure. The seCPT induced a strong cardiovascular and HPA axis response, and both systems were affected by the functional genetic variants, although methylation also predicted blood pressure reactivity. The return to baseline was predominantly influenced by the genomic sequence. Overall, the physiological response to the seCPT is controlled by an exquisite mix of genetic and epigenetic factors.

Glucocorticoid-induced leucine zipper (GILZ) inhibits B cell activation in systemic lupus erythematosus

OBJECTIVES

Systemic lupus erythematosus (SLE) is a serious multisystem autoimmune disease, mediated by disrupted B cell quiescence and typically treated with glucocorticoids. We studied whether B cells in SLE are regulated by the glucocorticoid-induced leucine zipper (GILZ) protein, an endogenous mediator of anti-inflammatory effects of glucocorticoids.

METHODS

We conducted a study of GILZ expression in blood mononuclear cells of patients with SLE, performed in vitro analyses of GILZ function in mouse and human B cells, assessed the contributions of GILZ to autoimmunity in mice, and used the nitrophenol coupled to keyhole limpet haemocyanin model of immunisation in mice.

RESULTS

Reduced B cell GILZ was observed in patients with SLE and lupus-prone mice, and impaired induction of GILZ in patients with SLE receiving glucocorticoids was associated with increased disease activity. GILZ was downregulated in naïve B cells upon stimulation in vitro and in germinal centre B cells, which contained less enrichment of H3K4me3 at the GILZ promoter compared with naïve and memory B cells. Mice lacking GILZ spontaneously developed lupus-like autoimmunity, and GILZ deficiency resulted in excessive B cell responses to T-dependent stimulation. Accordingly, loss of GILZ in naïve B cells allowed upregulation of multiple genes that promote the germinal centre B cell phenotype, including lupus susceptibility genes and genes involved in cell survival and proliferation. Finally, treatment of human B cells with a cell-permeable GILZ fusion protein potently suppressed their responsiveness to T-dependent stimuli.

CONCLUSIONS

Our findings demonstrated that GILZ is a non-redundant regulator of B cell activity, with important potential clinical implications in SLE.

The Treatment of Juvenile Fibromyalgia with an Intensive Physical and Psychosocial Program

OBJECTIVE

To assess the short-term and 1-year outcomes of children with fibromyalgia treated with intensive physical and occupational therapy (PT/OT) and psychotherapy.

STUDY DESIGN

Children with fibromyalgia seen at a tertiary care hospital were treated with 5-6 hours of intensive PT/OT daily and at least 4 hours of psychosocial services weekly. All medications used for fibromyalgia were discontinued. Children underwent standardized testing, including a visual analog scale for pain; the Bruininks-Oseretsky Test of Motor Performance, Second Edition; the Bruce treadmill protocol; the Functional Disability Inventory; the Pain Stages of Change Questionnaire, adolescent version; and the Pediatric Quality of Life Inventory, Teen Report, at 3 time points: at program entry, at the end of the intensive program, and 1 year after the end of the program.

RESULTS

Sixty-four children (median age, 16 years; 95% Caucasian; 94% female; median duration of symptoms, 21 months) were studied. The mean pain score decreased significantly from program entry to the end of the program (from 66 of 100 to 25 of 100; P = .001). At the 1-year follow-up, 33% reported no pain. All measures of function on the Bruininks-Oseretsky Test of Motor Performance, Second Edition improved significantly and remained at that level or continued to improve over the subsequent year. The mean Bruce treadmill protocol time first increased from 588 seconds to 801 seconds (P < .001) and then dropped to 750 seconds (P = .005), which is at the 90th percentile for age and sex. All Pain Stages of Change Questionnaire, adolescent version subset scores improved significantly initially and were stable or improved at 1 year, as did the Pediatric Quality of Life Inventory, Teen Report total score.

CONCLUSION

Children with fibromyalgia can be successfully treated without medications with a very intensive PT/OT and psychotherapy program. They have significantly improved pain and function by subject report and objective measures of function.

Ginsenoside Rh1 Improves the Effect of Dexamethasone on Autoantibodies Production and Lymphoproliferation in MRL/lpr Mice

Ginsenoside Rh1 is able to upregulate glucocorticoid receptor (GR) level, suggesting Rh1 may improve glucocorticoid efficacy in hormone-dependent diseases. Therefore, we investigated whether Rh1 could enhance the effect of dexamethasone (Dex) in the treatment of MRL/lpr mice. MRL/lpr mice were treated with vehicle, Dex, Rh1, or Dex + Rh1 for 4 weeks. Dex significantly reduced the proteinuria and anti-dsDNA and anti-ANA autoantibodies. The levels of proteinuria and anti-dsDNA and anti-ANA autoantibodies were further decreased in Dex + Rh1 group. Dex, Rh1, or Dex + Rh1 did not alter the proportion of CD4+ splenic lymphocytes, whereas the proportion of CD8+ splenic lymphocytes was significantly increased in Dex and Dex + Rh1 groups. Dex + Rh1 significantly decreased the ratio of CD4+/CD8+ splenic lymphocytes compared with control. Con A-induced CD4+ splenic lymphocytes proliferation was increased in Dex-treated mice and was inhibited in Dex + Rh1-treated mice. Th1 cytokine IFN-γ mRNA was suppressed and Th2 cytokine IL-4 mRNA was increased by Dex. The effect of Dex on IFN-γ and IL-4 mRNA was enhanced by Rh1. In conclusion, our data suggest that Rh1 may enhance the effect of Dex in the treatment of MRL/lpr mice through regulating CD4+ T cells activation and Th1/Th2 balance.

Knockdown of steroid receptors in the central nucleus of the amygdala induces heightened pain behaviors in the rat

Previously we demonstrated that exposure of the central nucleus of the amygdala (CeA) to elevated corticosterone (CORT) induces nociceptive behaviors that are reversed by glucocorticoid and/or mineralocorticoid (GR/MR) receptor antagonism. Here we test the hypothesis that in a cholesterol (CHOL)-implanted control rat, selective knockdown of GR/MR in the CeA would, via a corticotropin-releasing factor (CRF)-mediated mechanism, replicate the nociceptive behaviors produced by elevated amygdala CORT. Micropellets of CHOL or CORT were stereotaxically placed on the dorsal margin of the CeA. Cannulae were implanted into the CeA for the delivery of vehicle or oligodeoxynucleotide (ODN) of either antisense (ASO) or random sequences (RSO) targeting GR or MR. Visceromotor behavioral response quantified visceral sensitivity in response to colonic distension, while von Frey filaments assessed somatic sensitivity. Receptor expression was determined with qRT-PCR. In CHOL implanted controls, knockdown of GR in the CeA increased both colonic and somatic sensitivity, whereas selective knockdown of MR in the CeA induced colonic hypersensitivity without affecting somatic sensitivity. CRF expression in the CeA was increased in CHOL-implanted rats treated with GR or MR ASO and resembled the augmented CRF expression seen in the CORT-implanted rats. This is the first study to demonstrate that decreasing either GR or MR within the CeA is sufficient to induce visceral hypersensitivity whereas somatic hypersensitivity developed after only GR knockdown. The loss of either GR or MR was associated with an increased CRF expression, and may represent a common mechanism for the development of CeA-mediated nociceptive behaviors.

Reduced hypothalamic-pituitary-adrenal axis activity in chronic multi-site musculoskeletal pain: partly masked by depressive and anxiety disorders

BACKGROUND

Studies on hypothalamic-pituitary-adrenal axis (HPA-axis) function amongst patients with chronic pain show equivocal results and well-controlled cohort studies are rare in this field. The goal of our study was to examine whether HPA-axis dysfunction is associated with the presence and the severity of chronic multi-site musculoskeletal pain.

METHODS

Data are from the Netherlands Study of Depression and Anxiety including 1125 subjects with and without lifetime depressive and anxiety disorders. The Chronic Pain Grade questionnaire was used to determine the presence and severity of chronic multi-site musculoskeletal pain. Subjects were categorized into a chronic multi-site musculoskeletal pain group (n = 471) and a control group (n = 654). Salivary cortisol samples were collected to assess HPA-axis function (awakening level, 1-h awakening response, evening level, diurnal slope and post-dexamethasone level).

RESULTS

In comparison with the control group, subjects with chronic multi-site musculoskeletal pain showed significantly lower cortisol level at awakening, lower evening level and a blunted diurnal slope. Lower cortisol level at awakening and a blunted diurnal slope appeared to be restricted to those without depressive and/or anxiety disorders, who also showed a lower 1-h awakening response.

CONCLUSIONS

Our results suggest hypocortisolemia in chronic multi-site musculoskeletal pain. However, if chronic pain is accompanied by a depressive or anxiety disorder, typically related to hypercortisolemia, the association between cortisol levels and chronic multi-site musculoskeletal pain appears to be partly masked. Future studies should take psychopathology into account when examining HPA-axis function in chronic pain.

The role of vitamin D in pathophysiology and treatment of fibromyalgia

Recent studies showed that most cells have receptors and enzymes responsible for metabolism of vitamin D. Several diseases have been linked to vitamin D deficiency, such as hypertension, diabetes, depression, Alzheimer's disease, Parkinson's disease, multiple sclerosis, and chronic pain syndromes such as fibromyalgia. The association between fibromyalgia and vitamin D deficiency is very controversial in the literature with conflicting studies and methodological problems, which leads to more questions than answers. The purpose of this article is to raise questions about the association of hypovitaminosis D with fibromyalgia considering causal relationships, treatment, and pathophysiological explanations.

Gene expression profiles of fatigued fibromyalgia patients with different categories of pain and catastrophizing: a preliminary report

BACKGROUND

Fibromyalgia (FM) is a chronic condition characterized by diffused musculoskeletal pain and overwhelming fatigue.

PURPOSE

To compare the gene expression profiles of fatigued FM women with different levels of pain and catastrophizing.

METHODS

Nine women with FM enrolled in an active Medstar Research Institute protocol were included in the gene expression analyses of peripheral blood RNA via Affymetrix GeneChip Human Genome U133 Plus 2.0 array (Santa Clara, CA). Scores from Brief Pain Inventory, Pain Catastrophizing Scale, and Multidimensional Fatigue Inventory categorized the nine participants into pain (high, n = 3; low, n = 6) and catastrophizing groups (high, n = 5; low, n = 4).

DISCUSSION

Differential expression of 107 genes between the high and low pain groups and 139 genes between the high and low catastrophizing groups (over 2.0-fold change, p < .05) were observed. Network analyses showed interferon signaling and interferon regulatory activation factor pathways distinguished between the pain groups whereas dendritic cell maturation delineated between the catastrophizing groups.

CONCLUSION

Findings provide preliminary evidence that specific physiological pathways may possibly delineate pain and catastrophizing mechanisms. Further investigation via the use of a larger and more homogenous sample is warranted.

Ex vivo stimulation of whole blood as a means to determine glucocorticoid sensitivity

PURPOSE

Glucocorticoids are commonly prescribed to treat a number of diseases including the majority of inflammatory diseases. Despite considerable interpersonal variability in response to glucocorticoids, an insensitivity rate of about 30%, and the risk of adverse side effects of glucocorticoid therapy, currently no assay is performed to determine sensitivity.

PATIENTS AND METHODS

Here we propose a whole blood ex vivo stimulation assay to interrogate known glucocorticoid receptor (GR) up- and downregulated genes to indicate glucocorticoid sensitivity. We have chosen to employ real-time PCR in order to provide a relatively fast and inexpensive assay.

RESULTS

We show that the GR-regulated genes, GILZ and FKBP51, are upregulated in whole blood by treatment with dexamethasone and that LPS-induction of cytokines (IL-6 and TNFα) are repressed by dexamethasone in a dose responsive manner. There is considerable interpersonal variability in the maximum induction of these genes but little variation in the EC(50) and IC(50) concentrations. The regulation of the GR-induced genes differs throughout the day whereas the suppression of LPS-induced cytokines is not as sensitive to time of day.

CONCLUSION

In all, this assay would provide a method to determine glucocorticoid receptor responsiveness in whole blood.

Evidence for an association between an enhanced reactivity of interleukin-6 levels and reduced glucocorticoid sensitivity in patients with fibromyalgia

Pain and fatigue have been identified as core symptoms of fibromyalgia syndrome (FMS). Since both symptoms are also characteristic of hypocortisolemic disorders, reduced cortisol levels have been thought to promote an exacerbation of these FMS core symptoms by an enhanced reactivity of interleukin-6 (IL-6) levels. The aim of the current study was to investigate the pathophysiologic relevance of reduced cortisol levels for manifestation of FMS core symptoms. Twelve female FMS patients with 15 female controls were compared regarding the function of hypothalamus-pituitary-adrenal (HPA) axis and behavioral, endocrine and IL-6 responses after measuring the pressure pain thresholds (PPTs) at tender points. Function of HPA axis was assessed by determining the cortisol awakening response, daytime profile of cortisol secretion, low dose overnight dexamethasone suppression test (DST) and glucocorticoid sensitivity (GC) of inflammatory cytokine production. While endocrine and IL-6 responses were determined by collecting blood and saliva samples behavioral responses were assessed by pain and fatigue recordings of participants before and after PPT measurement using visual analogue scale (VAS). Whereas FMS patients were found not to differ from controls in cortisol awakening response, daytime profile of cortisol secretion and cortisol suppression after overnight DST, they did exhibit a reduced GC sensitivity of inflammatory cytokine production. PPT measurement did induce three times higher cortisol and four times higher IL-6 levels in FMS patients, but no change in their ACTH levels. The enhanced IL-6 reactivity after PPT measurement was accompanied by an increase in the severity of FMS patients' pain and fatigue ratings. The findings of the present study provide evidence for the pathophysiologic relevance of a disturbed glucocorticoid receptor (GR) function, rather than reduced cortisol levels for the maintenance of FMS core symptoms.

Genetics and Gene Expression Involving Stress and Distress Pathways in Fibromyalgia with and without Comorbid Chronic Fatigue Syndrome

In complex multisymptom disorders like fibromyalgia syndrome (FMS) and chronic fatigue syndrome (CFS) that are defined primarily by subjective symptoms, genetic and gene expression profiles can provide very useful objective information. This paper summarizes research on genes that may be linked to increased susceptibility in developing and maintaining these disorders, and research on resting and stressor-evoked changes in leukocyte gene expression, highlighting physiological pathways linked to stress and distress. These include the adrenergic nervous system, the hypothalamic-pituitary-adrenal axis and serotonergic pathways, and exercise responsive metabolite-detecting ion channels. The findings to date provide some support for both inherited susceptibility and/or physiological dysregulation in all three systems, particularly for catechol-O-methyl transferase (COMT) genes, the glucocorticoid and the related mineralocorticoid receptors (NR3C1, NR3C2), and the purinergic 2X4 (P2X4) ion channel involved as a sensory receptor for muscle pain and fatigue and also in upregulation of spinal microglia in chronic pain models. Methodological concerns for future research, including potential influences of comorbid clinical depression and antidepressants and other medications, on gene expression are also addressed.

Meta-analysis and meta-regression of hypothalamic-pituitary-adrenal axis activity in functional somatic disorders

Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis is the most investigated biological risk marker in functional somatic disorders (FSDs), such as chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS). Our aim was to assess whether there is an association between basal hypocortisolism and FSD and to identify potential moderators of this association. Meta-analysis on 85 studies revealed that although basal cortisol levels were generally lower in FSD subjects compared to controls, this association did not reach statistical significance (SMD -0.07, 95% CI -0.17 to 0.04, p=0.241). However, when the three FSD were assessed separately, statistically significant basal hypocortisolism was observed in CFS subjects compared to controls (SMD -0.14, 95% CI -0.28 to 0.00, p=0.047), but not in FM or IBS. When all potential moderators were entered into a meta-regression analysis, only type of FSD and female gender were significant independent predictors of basal hypocortisolism. In conclusion, we did not find evidence to consider all three main FSD as hypocortisolemic disorders, as significant reduction in basal cortisol compared to healthy controls was only found in CFS and in females with FM, but not in IBS.

Fibromyalgia syndrome is associated with hypocortisolism

BACKGROUND

Fibromyalgia syndrome (FMS) is a disease of unknown pathogenesis characterized by chronic musculoskeletal pain. FMS has been also associated with altered endocrinological responses, but findings are inconsistent.

PURPOSE

The aim of the present study was to investigate free salivary cortisol levels in FMS patients compared with healthy controls with a particular focus on the cortisol awakening response (CAR). The saliva samples were collected in a controlled hospital-hotel setting, in which the participants' compliance was high and a number of potential confounders were analyzed.

METHOD

Twenty-nine chronic female FMS patients and 29 age-matched healthy female controls were recruited. Salivary cortisol samples were investigated eight times: in the afternoon when participants arrived at the hospital, after stress provocation (to be reported separately), in the evening, before they went to sleep, upon awakening, 30 and 60 min later, and during the afternoon of the second day. Questionnaires measuring pain levels, sleeping problems, perceived stress, and personality were administered to the participants. Other psychophysiological measurements were used to assess sleep quality and heart rate.

RESULTS

Patients with FMS had significantly lower cortisol levels during the day, most pronounced in the morning (CAR). The potential confounders analyzed did not influence the results. As expected, FMS patients reported more pain, stress, sleeping problems, anxiety, and depression.

CONCLUSION

The results lend support to the hypothesis of a dysfunction in the hypothalamus-pituitary-adrenal axis in FMS patients, with generally lower cortisol values, most pronounced upon awakening (CAR).

Sex differences in hypothalamic-pituitary-adrenal axis function in patients with chronic pain syndrome

Chronic pain is often equated with chronic stress yet the relationship between chronic pain and hypothalamic-pituitary-adrenal (HPA) axis activity is poorly understood. The objective of this study was to examine diurnal functioning of the HPA axis in patients with clinically defined non-inflammatory chronic pain syndrome (CPS) compared to controls. The sample consisted of 37 adults with CPS and 47 healthy controls. All participants provided saliva samples at awakening, 12:00, 18:00 and 21:00 h on two consecutive days, as well as completing self-report questionnaires relating to anxiety and depression. The CPS group had a significantly lower overall mean diurnal salivary cortisol concentration compared to the control group (p < 0.01) but no significant differences were found between the two groups for repeated cortisol sampling across the day. However, a three-way interaction of time of day by patient status by sex was found (p < 0.032), with lower cortisol concentration in male patients compared to female patients in the afternoon period. No significant group effect was found for the rate of decline in the circadian rise in cortisol concentration. These data demonstrate that CPS is associated with a degree of hypocortisolemia, particularly in male patients. The altered dynamics of cortisol secretion in CPS in relation to the onset and duration of pain in patients remains to be determined.