Altered Glucocorticoid Sensitivity Research Articles

Genetic glucocorticoid receptor variants differ between ethnic groups but do not explain variation in age of diabetes onset, metabolic and inflammation parameters in patients with type 2 diabetes.

The effect of excess glucocorticoid receptor (GR) stimulation through glucocorticoid medication or cortisol on glucose metabolism is well established. There are genetic GR variants that result in increased or decreased GR stimulation. We aimed to determine the prevalence of genetic GR variants in different ethnic groups in a cohort of patients with type 2 diabetes, and we aimed to determine their association with age of diabetes onset and metabolic and inflammation parameters. A cross-sectional analysis was performed in a multiethnic cohort (n = 602) of patients with established type 2 diabetes. Polymorphisms in the GR gene that have previously been associated with altered glucocorticoid sensitivity (TthIIII, ER22/23EK N363S, BclI and 9β) were determined and combined into 6 haplotypes. Associations with age of diabetes onset, HbA1c, hs-CRP and lipid values were evaluated in multivariate regression models. The prevalence of the SNPs of N363S and BclI was higher in Dutch than in non-Dutch patients. We observed a lower prevalence of the SNP 9β in Dutch, South(East) Asian and Black African patients versus Turkish and Moroccan patients. We did not detect an association between SNPs and diabetes age of onset or metabolic parameters. We only found a trend for lower age of onset and higher HbA1c in patients with 1 or 2 copies of haplotype 3 (TthIIII + 9β). The prevalence of genetic GR variants differs between patients of different ethnic origins. We did not find a clear association between genetic GR variants and age of diabetes onset or metabolic and inflammation parameters. This indicates that the clinical relevance of GR variants in patients with established type 2 diabetes is limited.

Glucocorticoid sensitivity and inflammatory status of peripheral blood mononuclear cells in patients with coronary artery disease

Objective: Mechanisms behind sustained inflammation in patients with coronary artery disease (CAD) are not clarified but hypothalamus-pituitary-adrenal (HPA) axis dysfunction may have a role. Here, we investigated whether inflammatory status of peripheral blood mononuclear cells (PBMCs) was associated with altered glucocorticoid sensitivity in CAD patients.Methods: In 55 CAD patients and 30 controls, mRNA levels of GR-α, GR-β, NF-κB, IκBα, MMP-9 and TIMP-1 were measured in PBMCs. Suppressive effects of dexamethasone on GR-α, GR-β, NF-κB, IκBα, MMP-9 and TIMP-1 mRNA levels were assessed in PBMCs ex vivo. Salivary cortisol was repeatedly measured over 3 days.Results: GR-α mRNA levels were higher in CAD patients than in controls, 0.50 (0.38–0.59) versus 0.26 (0.18–0.37), p < .001, while GR-β mRNA levels were equally low in both groups. GR-α mRNA expression was associated with inflammatory gene expression and, also, with flatter diurnal cortisol rhythm. In both patients and controls, dexamethasone suppressed gene expression of NF-κB, IκBα, MMP-9 and TIMP-1 (p < .001). Dexamethasone also reduced GR-α mRNA levels (p < .001), while LPS increased it (p < .001).Conclusions: PBMCs from CAD patients displayed an inflammatory gene expression profile. This was not explained by reduced glucocorticoid sensitivity. Instead, inflammation was associated with increased expression of GR-α mRNA, suggesting a hypocortisolemic state.Key messages • Peripheral blood mononuclear cells from patients with coronary artery disease (CAD) display an inflammatory gene expression profile. • This inflammatory state cannot be explained by reduced glucocorticoid sensitivity in CAD patients. • Instead, the inflammatory gene expression profile is associated with upregulated levels of glucocorticoid receptor-α mRNA, suggesting a hypocortisolemic state.

MiR-30c is specifically repressed in patients with active pulmonary tuberculosis

Tuberculous pleurisy (PLTB) is a common form of extrapulmonary tuberculosis. It often resolves without chemotherapy being hence considered a rather benign manifestation of the disease. Patients with PLTB mount an effective anti-mycobacterial response, unlike those with active pulmonary TB (pTB) that were shown to present an imbalance in plasma immune and endocrine mediators. In this work, we explored whether expression of the active isoform of the glucocorticoid receptor (hGRα) in the context of the inflammatory-anti-inflammatory responses of TB patients may be associated to microRNA levels. As expected, the inflammatory response triggered in patients coexists with increased circulating cortisol and altered hGRα levels in the peripheral blood mononuclear cells. However, while hGRα expression is significantly downregulated in PLTB, its levels in pTB patients are higher within the control values. These results point out to the existence of an additional mechanism tending to preserve hGRα levels probably to deal with the chronic inflammation observed in pTB. In this regard, we found that miR-30c is strongly downregulated in mononuclear cells of pTB patients compared to PLTB cases, showing an expression profile opposite to that seen with hGRα. Interestingly, low levels of miR-30c are specific for this active form of TB, as its expression is not altered in mononuclear cells from either healthy controls or patients with tuberculous or non-tuberculous pleurisy. Moreover, miR-30c and hGRα also showed an inverse expression pattern in M. tuberculosis-stimulated THP-1 macrophage cultures. In sum, our studies identify miR-30c as a specific correlate of pulmonary manifestations of TB, potentially involved in the altered glucocorticoid sensitivity observed in these patients.

Glucocorticoid receptor polymorphism in obesity and glucose homeostasis.

Glucocorticoid receptor (GR) activity plays a significant role in the etiology of obesity and is essential for glucose homeostasis, the development of hyperinsulinaemia and subsequent increased fat deposition. Several polymorphisms in the GR gene have been described, and at least three of them seem to be associated with altered glucocorticoid sensitivity and changes in glucose homeostasis, and other metabolic parameters. The N363S polymorphism has been associated with increased sensitivity to glucocorticoides, increased insulin response to dexamethasone and increased plasma glucose level. BclI polymorphism is associated with increased abdominal obesity, hyperinsulinaemia and increased insulin resistance. Another polymorphism, ER22/23EK, in contrast to the others, is associated with relative resistance to glucocoricides actions and more beneficial metabolic profile-lower insulin resistance level, decreased lower cardiovascular risk and subseuent prolongation of life time. More research is still needed to understand the mechanisms behind these associations at the molecular level.

LUMAN/CREB3 is a key regulator of glucocorticoid-mediated stress responses

Altered glucocorticoid sensitivity is believed to contribute to a number of human diseases, including inflammatory and autoimmune conditions as well as disorders characterized by abnormal hypothalamic-pituitary-adrenal axis (HPA) function. LUMAN (or CREB3), originally identified through its interaction with a cell cycle regulator HCFC1, is an endoplasmic reticulum membrane-bound transcription factor that is involved in the unfolded protein response. Here we demonstrate that LUMAN changes the glucocorticoid response by modulating the expression of the glucocorticoid receptor leading to an overall increase in GR activity. Luman-deficient mice exhibited a blunted stress response characterized by low levels of both anxiety and depressive-like behaviour in addition to low circulating corticosterone levels. These mice also have reduced dendritic branching in the CA3 region of the hippocampus, consistent with increased GR responses. These findings are consistent with the notion that elevated GR activities are the primary cause of the observed phenotype in these LUMAN-deficient mice. We thus postulate that LUMAN is a key regulator of GR-mediated signaling and modulates HPA axis reactivity.

Immunopathology alters Th17 cell glucocorticoid sensitivity.

Th17 cells contribute to several inflammatory conditions and increasing evidence supports that Th17 cells are glucocorticoid resistant. However, Th17 cells in psoriasis and related diseases are glucocorticoid sensitive. We compare glucocorticoid sensitive and resistant immunological diseases and suggest that several aspects in Th17-related diseases alter glucocorticoid sensitivity of Th17 cells. We identify molecular pathways that are implicated in glucocorticoid sensitivity of Th17 cells in the literature, as this information is useful for developing approaches to overcome glucocorticoid-resistant immunopathology.

Glucocorticoid receptor polymorphisms modulate cardiometabolic risk factors in patients in long-term remission of Cushing’s syndrome

ContextGlucocorticoid receptor (GR) polymorphisms modulate glucocorticoid (GC) sensitivity and are associated with altered metabolic profiles.ObjectiveTo evaluate the presence of GR polymorphisms (BclI (rs41423247), N363S (rs56149945), ER22/23EK (rs6189/rs6190), and 9β (rs6198) and investigate their associations with metabolic alterations in patients in long-term remission of Cushing’s syndrome (CS).Design and settingCross-sectional case–control study.Patients and methodsSixty patients in long-term remission of CS were genotyped. Associations between GR polymorphisms and multiple vascular, body composition and metabolic parameters were investigated.Main outcome measuresAllelic frequencies of the polymorphisms and their associations with several cardiometabolic risk factors.ResultsThis study shows that carriers of the 9β polymorphism have a higher systolic blood pressure and lower resistin levels. The GC sensitizing BclI polymorphism is associated with an adverse cardiometabolic risk factor profile: higher fat percentages of extremities and legs, higher serum leptin and E-selectin levels, and higher intima media thickness in carriers versus non-carriers.ConclusionsThe 9β and BclI polymorphisms of the GR adversely affect the cardiometabolic profile in patients who are in remission after the treatment of CS. This suggests that genetically altered GC sensitivity modulates the long-term adverse cardiometabolic effects resulting from (endogenous) hypercortisolism.

Polymorphisms in NR3C1 gene associated with risk of metabolic syndrome in a Chinese population

Polymorphisms of the NR3C1 (glucocorticoid receptor) gene have been reported to be associated with altered glucocorticoids sensitivity and changes in body composition and metabolic parameters. This study explored the relationship between single nucleotide polymorphisms (SNPs) of the NR3C1 gene and metabolic syndrome (MetS) in a Chinese population. Fourteen tag-SNPs and five functionally important SNPs in the NR3C1 gene were genotyped in MetS patients (n = 431) and normal controls (n = 461) using the high-throughput Sequenom genotyping platform. Genotype, allelic and haplotype associations were examined using logistic regression and Haploview. There are four SNPs significantly associated with MetS. The T allele of rs2963156 was associated with an increased risk effect for MetS (adjusted OR = 1.66, 95 % CI 1.25-2.22, P = 0.001). By contrast, rs10052957 A allele carriers were significantly associated with a decreased risk of MetS (adjusted OR = 0.58, 95 % CI 0.42-0.80, P = 0.001). Rs41423247 GG genotype (adjusted OR = 2.01, 95 % CI 1.25-3.22, P = 0.004), and rs7701443 AA genotype (adjusted OR = 1.88, 95 % CI 1.24-2.83, P = 0.003) were significantly associated with an increased risk of MetS. Haplotype CGGA is risk conferring (adjusted OR = 1.53, 95 % CI 1.06-2.20, P = 0.023), whereas haplotype CCAG was protective (adjusted OR = 0.30, 95 % CI 0.20-0.47, P < 0.001). Polymorphism of NR3C1 gene is associated with MetS and may contribute to the susceptibility of MetS.

9β Polymorphism of the Glucocorticoid Receptor Gene Appears to Have Limited Impact in Patients with Addison’s Disease

BackgroundAddison’s disease (AD) has been associated with an increased risk of cardiovascular disease. Glucocorticoid receptor polymorphisms that alter glucocorticoid sensitivity may influence metabolic and cardiovascular risk factors in patients with AD. The 9β polymorphism of the glucocorticoid receptor gene is associated with relative glucocorticoid resistance and has been reported to increase the risk of myocardial infarction in the elderly. We explored the impact of this polymorphism in patients with AD.Materials and Methods147 patients with AD and 147 age, gender and ethnicity matched healthy controls were recruited. Blood was taken in a non-fasted state for plasma lipid determination, measurement of cardiovascular risk factors and DNA extraction.ResultsGenotype data for the 9β polymorphism was available for 139 patients and 146 controls. AD patients had a more atherogenic lipid profile characterized by an increase in the prevalence of small dense LDL (p = 0.003), increased triglycerides (p = 0.002), reduced HDLC (p<0.001) an elevated highly sensitive C-reactive protein (p = 0.01), compared with controls. The 9β polymorphism (at least one G allele) was found in 28% of patients and controls respectively. After adjusting for age, gender, ethnicity, BMI and hydrocortisone dose per metre square of body surface area in patients, there were no significant metabolic associations with this polymorphism and hydrocortisone doses were not higher in patients with the polymorphism.ConclusionsThis study did not identify any associations between the 9β polymorphism and cardiovascular risk factors or hydrocortisone dose and determination of this polymorphism is therefore unlikely to be of clinical benefit in the management of patients with AD.

Modulatory effect of BclI GR gene polymorphisms on the obesity phenotype in Brazilian patients with Cushing's disease

OBJECTIVES:Patients with Cushing's disease exhibit wide phenotypic variability in the severity of obesity, diabetes and hypertension. In the general population, several glucocorticoid receptor genes (NR3C1) and HSD11B1 polymorphisms are associated with altered glucocorticoid sensitivity and/or metabolism, resulting in an increased or reduced risk of an adverse metabolic profile. Our aim was to analyze the association of NR3C1 and HSD11B1 gene variants with the severity of some clinical and hormonal features of Cushing's disease.METHODS:Sixty-four patients presenting with Cushing's disease were diagnosed based on adrenocorticotrophic hormone levels, high-dose dexamethasone suppression tests and/or inferior petrosal sinus sampling and magnetic resonance imaging. The A3669G, ER22/23EK, N363S BclI-NR3C1 and HSD11B1-rs12086634 variants were screened.RESULTS:The BclI, HSD11B1-rs12086634 and A3669G variants were found in 36%, 19.5% and 14% of alleles, respectively. The N363S and ER22/23EK polymorphisms were identified in heterozygosis once in only two patients (1.5% of alleles). There were no differences in the weight gain or prevalence of diabetes and hypertension in the patients carrying the abovementioned alleles compared to the wild-type carriers. Interestingly, the mean body mass index (BMI) of the BclI carriers was significantly higher than the non-carriers (34.4±7 kg/m2 vs. 29.6±4.7 kg/m2, respectively). None of the polymorphisms were associated with the basal adrenocorticotrophic hormone, FU levels or F level after dexamethasone suppression testing.CONCLUSION:Although Cushing's disease results from increased glucocorticoid secretion, we observed that interindividual variability in the peripheral glucocorticoid sensitivity, mediated by the glucocorticoid receptor, could modulate the obesity phenotype.

BClI polymorphism of the glucocorticoid receptor gene is associated with increased obesity, impaired glucose metabolism and dyslipidaemia in patients with Addison's disease

Although glucocorticoids are essential for health, several studies have shown that glucocorticoids replacement in Addison's disease might be involved in anthropometric and metabolic impairment, with increased cardiovascular risk, namely if conventional doses are used. As the effects of glucocorticoids are mediated by the glucocorticoid receptor, encoded by NR3C1 gene, different polymorphisms in the NR3C1 gene have been linked to altered glucocorticoid sensitivity in general population as well as in patients with obesity or metabolic syndrome. We investigated the impact of glucocorticoid receptor gene polymorphisms, including the BclI, N363S and ER22/23EK variants, on anthropometric parameters (BMI and waist circumference), metabolic profile (HOMA, OGTT and serum lipids) and ACTH levels in 50 patients with Addison's disease (34 women and 16 men, age 20-82 year) under glucocorticoids replacement. Neither N363S nor ER22/23EK variants were significantly associated with anthropometric, metabolic or hormonal parameters, while patients carrying the homozygous BclI polymorphism GG (n = 4) showed higher (P < 0·05) BMI, waist circumference, HOMA and 2-h glucose levels after OGTT, as well as total cholesterol and triglycerides than those with wild-type genotype CC (n = 28) or heterozygous CG (n = 18). The totality of GG patients was connoted by abdominal adiposity, impaired glucose tolerance/diabetes mellitus or dyslipidaemia, while a lower percentage of CC or CG patients showed some anthropometric and metabolic alterations. These results suggest that BclI polymorphism may influence the sensitivity to glucocorticoids in patients with Addison's disease and may contribute, along with other factors, to the increase in central adiposity, impaired glucose metabolism and dyslipidaemia.

9. Dysregulated diurnal cortisol pattern and increased glucocorticoid resistance among pre-menopausal women with major depressive disorder

Women are approximately twice as likely to experience depression compared to men and are at significantly greater risk for developing comorbid physical health conditions, including diabetes, chronic inflammatory diseases, and cardiovascular disease, suggesting a possible common mechanism for the psychological and physical health risks seen in depression. We examined one biological pathway that may underlie these effects by investigating the extent to which HPA axis activity was dysregulated in 26 women with current major depression and 23 age- and BMI-matched psychiatrically healthy women. Salivary cortisol samples were collected at wakening, 30 min later, and at bedtime over three consecutive days. Depressed women exhibited flatter diurnal cortisol slopes compared to non-depressed women ( F 2 = 5.52, p = .004). To investigate whether these differences could be attributed to differences in glucocorticoid feedback sensitivity, saliva samples were also collected on a fourth consecutive day after participants self-administered dexamethasone. Analyses revealed that depressed women exhibited a dampened response to dexamethasone compared to non-depressed women ( F 1 = 6.04, p = .015). These findings are consistent with previous studies showing that depression is associated with altered HPA axis regulation, but extend this work by showing that reduced hypothalamic and pituitary sensitivity to negative feedback from glucocorticoids is one mechanism that may explain this effect. Altered glucocorticoid sensitivity may play a role in promoting depression as well as the physical health complications that frequently co-occur with this serious psychiatric disorder.

P02-213 - Association study between glucocorticoid receptor polymorphisms and personality traits in healthy subjects

AimsPrevious studies have shown that the function of hypothalamic-pituitary-adrenal (HPA) axis is involved in the characterization of personality traits. Glucocorticoid receptor (GR) is the most important regulator of the HPA axis negative feedback system, and several polymorphisms of the GR gene are associated with altered glucocorticoid sensitivity. In the present study, we examined the associations between the GR polymorphisms and personality traits in healthy subjects.MethodsSubjects were 880 Japanese healthy volunteers. Personality traits were assessed by the Temperament and Character Inventory (TCI). Two polymorphisms of the GR gene, i.e., G/C SNP in the intron 2 (BcII polymorphism, rs41423247) and A/G SNP in the exon 9β (9β polymorphism, rs6198), were detected by a real-time PCR and cycling probe technology for SNP typing.ResultsThe genotype distributions were G/G = 614, G/C = 240, and C/C = 26 for the BcII polymorphism, and A/A = 879 and A/G = 1 for the 9β polymorphism, respectively. There were no significant associations between the BcII genotype groups in any TCI dimension score.ConclusionThe present study suggests that these two GR polymorphisms (BcII and 9β polymorphism) are not involved in the characterization of personality traits in healthy subjects.

A Glucocorticoid Receptor Gene Haplotype (TthIII1/ER22/23EK/9β) Is Associated with a More Aggressive Disease Course in Multiple Sclerosis

In patients with multiple sclerosis (MS), glucocorticoids (GCs) might not be sufficiently able to restrain the immune system, possibly due to decreased GC sensitivity. This may be, at least partially, genetically determined. Previously, we reported a more aggressive disease course in patients with the glucocorticoid receptor (GR) gene ER22/23EK polymorphism, which has been shown to decrease GC sensitivity. In 646 MS patients and 317 healthy controls, we investigated whether haplotypes, including the ER22/23EK polymorphism or the GR 9beta polymorphism, which is also associated with a relative GC resistance, were associated with a more aggressive disease course. Polymorphisms in the GR gene (9beta, ER22/23EK, TthIIII, BclI, and N363S), which have previously been associated with altered GC sensitivity were determined and haplostructure was characterized. We evaluated whether the haplotypes were associated with disease susceptibility and several other disease characteristics. The association with disease progression was analyzed using Cox regression with time to Expanded Disability Status Score 6 as outcome. None of the haplotypes was associated with disease susceptibility, age at onset, or onset type. Haplotype 6 (TthIIII, ER2223EK, and 9beta-G) was associated with a more rapid disease progression (hazard ratio 2.3; 95% confidence interval 1.5-3.7; P < 0.001). This seems to result from the presence of ER22/23EK, and not from the 9beta and TthIIII polymorphisms. MS patients carrying the haplotype 6 (TthIIII, ER22/23EK, and 9beta) have a more aggressive disease course. This is probably due to the presence of the polymorphism ER22/23EK, which causes a decreased GC sensitivity.

Two Common Haplotypes of the Glucocorticoid Receptor Gene Are Associated with Increased Susceptibility to Cardiovascular Disease in Men with Familial Hypercholesterolemia

Glucocorticoids contribute to the development of atherosclerosis. Four polymorphisms in the glucocorticoid receptor (GR) gene have been reported to alter glucocorticoid sensitivity and have been associated with cardiovascular risk factors. Studies on the relationship between these GR variants and cardiovascular disease (CVD) risk, however, have yielded conflicting results. We sought to determine whether haplotypes based on functional polymorphisms in the GR gene influenced susceptibility to CVD in a high-risk population. In a multicenter cohort study, 1830 patients with heterozygous familial hypercholesterolemia were genotyped for the functional ER22/23EK, N363S, BclI, and 9beta variants. We analyzed the combined effect of all GR variants by constructing haplotypes and using a Cox proportional hazards regression model with adjustment for year of birth and smoking. The analyses were stratified for sex. The primary outcome measure was CVD defined as coronary, cerebral, and peripheral artery disease. A total of 359 men (40.8%) and 224 women (23.6%) had a cardiovascular event. In men, the BclI haplotype was associated with a 34% higher CVD risk (confidence interval 1.02-1.76; P = 0.03) and the 9beta haplotype with a 41% higher CVD risk (confidence interval 1.02-1.94; P = 0.04). In women, none of the GR haplotypes was significantly related with CVD. We did not find differences in cardiovascular risk factors between GR haplotypes. In this large cohort of high-risk individuals, two common haplotypes in the GR gene modified CVD susceptibility among men.

85. The glucocorticoid dexamethasone prevents inflammation-induced suppression of glial β 2-adrencoceptor expression: Implications for multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system, in which unknown environmental factors are thought to trigger disease in genetically susceptible persons. Glucocorticoids (GCs) play an important role in controlling chronic inflammatory diseases, like MS. Three polymorphisms in the glucocorticoid receptor (GR) gene (N363S, ER22/23EK and the Bcl I C/G) have been shown to alter glucocorticoid sensitivity, and therefore may influence disease course. We investigated the influence of these polymorphisms on clinical and MRI parameters. The ER22/23EK polymorphism was associated with a more aggressive MS phenotype, measured both clinically and on MRI.

Glucocorticoid receptor gene polymorphisms and glucocorticoid sensitivity of subdermal blood vessels and leukocytes

A considerable variability in the sensitivity to glucocorticoids (GCs) exists between individuals and these differences have been implicated in the etiology of psychiatric diseases such as depression. Glucocorticoid receptor (GR) gene polymorphisms might account in part for variability in GC responsiveness. We assessed the association between four common GR gene (NR3C1) polymorphisms (ER22/23EK, N363S, BclI, 9beta) and markers of glucocorticoid sensitivity in two target tissues (subdermal blood vessels, peripheral leukocytes) in 206 healthy individuals. The BclI GG genotype group showed the least degree of skin blanching, reflecting a lower GC sensitivity of subdermal blood vessels (p=.01). No association between GR genotype and GC sensitivity of peripheral leukocytes was observed. In the same subjects we previously observed an association between GR genotype and GC sensitivity of the pituitary. Polymorphism of the GR gene might constitute a vulnerability or protection factor for stress related disorders and altered GC sensitivity.

Glucocorticoid sensitivity of immune cells in severely fatigued adolescent girls: A longitudinal study

Fatigue during adolescence is associated with somatic and psychological complaints that resemble the pattern of symptoms described for chronic fatigue syndrome (CFS). Studies in CFS and other stress-related syndromes suggested a dysfunction of the interactions between the hypothalamic-pituitary-adrenal axis (HPA-axis) and the immune system, i.e. a changed glucocorticoid (GC) receptor sensitivity of immune cells, to exist. Here we investigated whether severely fatigued girls from a healthy population have altered cortisol production and immune cell sensitivity for the synthetic GC, dexamethasone (DEX). In a longitudinal design, we examined ex vivo DEX sensitivity of monocytes and of T-cell mitogen-induced responses of severely fatigued (N=65) and non-fatigued girls (N=60). Fatigued girls reported more severe comorbid complaints than non-fatigued participants across three measurements during 1 year (T1: spring, T2: autumn, T3: spring) and had higher plasma cortisol levels throughout the study. DEX sensitivity of T-cell mitogen-induced responses showed seasonal variation with increased sensitivity in autumn compared to spring. No systematic variation of monocyte glucocorticoid receptor (GR) sensitivity was observed. Significant rank correlations of DEX sensitivity of T-cell mitogen-induced responses between the three assessments during the year suggest a stable trait of immune function. Groups did not differ in DEX sensitivity on any of the read outs. However, in a persistently fatigued subgroup, sensitivity to DEX was significantly reduced on the level of interferon (IFN)-gamma production. These results show that although fatigued participants had severe (comorbid) complaints, only in the case when symptoms persisted, altered GC sensitivity of immune cells was observed.

Pathway interactions between MAPKs, mTOR, PKA, and the glucocorticoid receptor in lymphoid cells

BackgroundGlucocorticoids are frequently used as a primary chemotherapeutic agent in many types of human lymphoid malignancies because they induce apoptosis through activation of the glucocorticoid receptor, with subsequent alteration of a complex network of cellular mechanisms. Despite clinical usage for over fifty years, the complete mechanism responsible for glucocorticoid-related apoptosis or resistance remains elusive. The mitogen-activated protein kinase pathway is a signal transduction network that influences a variety of cellular responses through phosphorylation of specific target substrates, including the glucocorticoid receptor. In this study we have evaluated the pharmaceutical scenarios which converge on the mitogen-activated protein kinase pathway to alter glucocorticoid sensitivity in clones of human acute lymphoblastic CEM cells sensitive and refractory to apoptosis in response to the synthetic glucocorticoid dexamethasone.ResultsThe glucocorticoid-resistant clone CEM-C1-15 displays a combination of high constitutive JNK activity and dexamethasone-induced ERK activity with a weak induction of p38 upon glucocorticoid treatment. The cells become sensitive to glucocorticoid-evoked apoptosis after: (1) inhibition of JNK and ERK activity, (2) stimulation of the cAMP/PKA pathway with forskolin, or (3) inhibition of mTOR with rapamycin. Treatments 1–3 in combination with dexamethasone alter the intracellular balance of phospho-MAPKs by lowering JNK phosphorylation and increasing the level of glucocorticoid receptor phosphorylated at serine 211, a modification known to enhance receptor activity.ConclusionOur data support the hypothesis that mitogen-activated protein kinases influence the ability of certain malignant lymphoid cells to undergo apoptosis when treated with glucocorticoid. Activated/phosphorylated JNK and ERK appear to counteract corticoid-dependent apoptosis. Inhibiting these MAPKs restores corticoid sensitivity to a resistant clone of CEM cells. Forskolin, which activates the cAMP pathway, and rapamycin, which inhibits mTOR, also inhibit JNK. Further, the sensitizing treatments result in a largely dexamethasone-dependent increase in the total pool of glucocorticoid receptor phosphorylated at serine 211. The phospho-serine 211 receptor is known to be more potent in activating gene transcription and apoptosis. The interactive effects demonstrated here in reverting resistant cells to corticoid sensitivity could provide therapeutic clinical potential in the treatment of lymphoid malignancies.

Glucocorticoid receptor gene polymorphisms associated with more aggressive disease phenotype in MS

Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system, in which unknown environmental factors are thought to trigger disease in genetically susceptible persons. Glucocorticoids (GCs) play an important role in controlling chronic inflammatory diseases, like MS. Three polymorphisms in the glucocorticoid receptor (GR) gene (N363S, ER22/23EK and the Bcl I C/G) have been shown to alter glucocorticoid sensitivity, and therefore may influence disease course. We investigated the influence of these polymorphisms on clinical and MRI parameters. The ER22/23EK polymorphism was associated with a more aggressive MS phenotype, measured both clinically and on MRI.