Characterization of the BclI polymorphism in the glucocorticoid receptor gene

The relationship of the methylation status and polymorphism of glucocorticoid receptor gene (NR3C1) with attempted suicide or non-suicidal self-injury patients in schizophrenia

We aim to investigate the methylation of NR3C1 gene promotor and NR3C1 BclI polymorphism in schizophrenia (SCZ) patients with attempted suicide or non-suicidal self-injury (NSSI). A sample of 112 patients with SCZ was included in the study. Structured Clinical Interview for Diagnostic and Statistical Manual-Fourth Edition Axis I Disorders was used to confirm the diagnosis according to The Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision criteria. The patients were evaluated by data forms that had sociodemographic, suicidal behavior, and NSSI information. Methylation-specific polymerase chain reaction (PCR) was used to identify the methylation of the NR3C1 gene. The analysis of the BclI polymorphism of the NR3C1 gene was evaluated by using the PCR restriction fragment length polymorphism. Our results revealed that although the NR3C1 gene methylation was not statistically significantly different, there was a significant difference in NR3C1 genotype distribution among the SCZ groups with and without attempted suicide. SCZ patients carrying the CC genotype had a lower risk of attempted suicide (Odds Ratio [OR]: 0.421; 95% Confidence Interval [CI]: 0.183-0.970; p = 0.040), while having the GG genotype in SCZ patients was associated with a higher risk of attempted suicide (OR: 3.785; 95% Cl: 1.107-12.945; p = 0.042). Additionally, due to NSSI in SCZ patients, there were no significant differences in NR3C1 gene methylation and NR3C1 genotype distribution among the groups. We propose that the NR3C1 BclI polymorphism may be associated with attempted suicide in Turkish patients diagnosed with SCZ.

REVEALING THE MOLECULAR-GENETIC AND CLINICAL PREDICTORS OF GLUCOCORTICOID RESISTANCE IN PATIENTS WITH HAND ECZEMA

OBJECTIVE

The aim: To reveal the possible predictors of the glucocorticoid resistance in patients with hand eczema (HE) based on the demographic, clinical, and molecular-genetic data.

PATIENTS AND METHODS

Materials and methods: 143 patients with HE were included in the study. Demographic, clinical, biochemical (blood content of IgE, IL-17A, IL-2, 25(OH)D), and genetic (rs41423247 genotypes) data were obtained from all patients.

RESULTS

Results: After 2 weeks of treatment by glucocorticoids, all subjects were divided into "responder" and "non-responder" groups according to change of the Hand Eczema Severity Index (HECSI). Statistical analysis was done using SPSS (version 22.0.). Binary logistic regression was used to identify predictors of glucocorticoid resistance. P-value 0.05). The results of the multivariate regression showed that Bcl-1 G-allele (OR =3.83; P = 0.033), and severe eczema (OR = 2.52; P = 0.023) are linked with an elevated risk of glucocorticoid resistance in patients with hand eczema.

CONCLUSION

Conclusions: Insensitivity to glucocorticoids in HE patients is associated with NR3C1 gene Bcl-1 polymorphism, eczema severity and blood level of IL-17, IL-2, 25(OH)D. The final adjustment showed that minor C-allele of the Bcl-1 polymorphism and severe eczema are the strongest predictors of the glucocorticoid resistance.

Generalized and tissue specific glucocorticoid resistance

Glucocorticoids (GCs) are steroid hormones that influence several physiologic functions and are among the most frequently prescribed drugs worldwide. Resistance to GCs has been observed in the context of the familial generalized GC resistance (Chrousos' syndrome) or tissue specific GC resistance in chronic inflammatory states. In this review, we have summarized the major factors that influence individual glucocorticoid sensitivity/resistance. The fine-tuning of GC action is determined in a tissue-specific fashion that includes the combination of different GC receptor promoters, translation initiation sites, splice isoforms, interacting proteins, post-translational modifications, and alternative mechanisms of signal transduction.

Associations between the neuron-specific glucocorticoid receptor (NR3C1) Bcl-1 polymorphisms and suicide in cancer patients within the first year of diagnosis

Background

Cancer diagnosis is associated with an increased suicide risk, particularly within the first 1 year after diagnosis of cancer. Abnormal function of the hypothalamic–pituitary–adrenal axis has been implicated in the pathophysiology of depression and suicide. We examined genetic associations of the functional Bcl-1 polymorphism of (rs41423247) neuron-specific glucocorticoid receptor (NR3C1) gene, with death by suicide in cancer patients. Suicides occurring within a year of cancer diagnosis (‘early suicide’) were considered separately from those suicides during the second or subsequent year (‘late suicide’) after cancer diagnosis.

Methods

The subjects consisted of 343 cancer patients admitted to a general hospital in Seoul, South Korea from 1996 to 2009, of which 182 had died by suicide and 161 were alive on December 31, 2009. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue sample of patients with cancer. We conducted a case-control association analysis of Bcl-1 polymorphism of NR3C1 gene.

Results

Subjects carrying the GG genotype of Bcl-1 polymorphism were at increased risk of early suicide when compared to those carrying the CC genotype (OR 3.80, 95 % CI 1.02–14.16, p = .047). Similarly, those individuals carrying the GG genotype (recessive mode) had an increased risk of early suicide relative to the CC or CG genotype (OR 3.71, 95 % CI 1.03–13.43, p = .045). However, there were no differences in the genotype distributions of the NR3C1 Bcl-1 polymorphism between late suicide cases and controls.

Conclusions

Our findings suggest that the NR3C1 Bcl-1 polymorphisms may be involved in the susceptibility to suicide within the first year after cancer diagnosis among cancer patients in Korean population.

Single Nucleotide Polymorphisms in Pediatric Idiopathic Nephrotic Syndrome

Polymorphic variants in several molecules involved in the glomerular function and drug metabolism have been implicated in the pathophysiology of pediatric idiopathic nephrotic syndrome (INS), but the results remain inconsistent. We analyzed the association of eleven allelic variants in eight genes (angiopoietin-like 4 (ANGPTL4), glypican 5 (GPC5), interleukin-13 (IL-13), macrophage migration inhibitory factor (MIF), neural nitric oxide synthetase (nNOS), multidrug resistance-1 (MDR1), glucocorticoid-induced transcript-1 (GLCCI1), and nuclear receptor subfamily-3 (NR3C1)) in 100 INS patients followed up till adulthood. We genotyped variants using PCR and direct sequencing and evaluated estimated haplotypes of MDR1 variants. The analysis revealed few differences in SNP genotype frequencies between patients and controls, or in clinical parameters among the patients. Genotype distribution of MDR1 SNPs rs1236, rs2677, and rs3435 showed significant (p < 0.05) association with different medication regimes (glucocorticoids only versus glucocorticoids plus additional immunosuppressives). Some marginal association was detected between ANGPTL4, GPC5, GLCCI1, and NR3C1 variants and different medication regimes, number of relapses, and age of onset. Conclusion. While MDR1 variant genotype distribution associated with different medication regimes, the other analyzed gene variants showed only little or marginal clinical relevance in INS.

The prognostic value of glucocorticoid receptors for adult acute lymphoblastic leukemia

BACKGROUND

Therapeutic protocols used in adult acute lymphoblastic leukemia (ALL) are widely variable, and glucocorticoids (GCs) are essential components in ALL treatment. Therefore, this study aimed to evaluate the distribution of prominent glucocorticoid receptor (GR) gene polymorphic variants among adult ALL patients. We also investigated the association between GR messenger ribonucleic acid (mRNA) isoform expressions and the response to chemotherapy.

METHODS

Fifty-two newly diagnosed Philadelphia-negative adult ALL patients and 30 healthy control subjects were enrolled in this study. Genotyping was carried out using a polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis. GR mRNA isoform expressions were assayed by quantitative real-time PCR.

RESULTS

ALL patients in this study had a median age of 34 years (range, 18-75). GRα expression was associated with complete remission (P=0.03), while GRγ mRNA expression was significantly higher in GC resistant patients (P=0.032) and in non-responders (P=0.019). However, there were no significant associations with GC resistance. The BclI polymorphic variant of the GR gene was the most frequent in adult ALL patients and was not associated with the GC response. Both higher GRα expression and lower GRγ expression were associated with achievement of complete remission, while higher GRγ expression was associated with GC-resistance.

CONCLUSION

Our data suggest that the level of GR isoform expression may be useful in predicting GC response, achievement of complete remission, and better event-free survival in ALL patients. However, further evaluation with a larger cohort of patients is warranted.

Genetic modulation of neural response during working memory in healthy individuals: interaction of glucocorticoid receptor and dopaminergic genes

Suboptimal performance in working memory (WM) tasks and inefficient prefrontal cortex functioning are related to dysregulation of dopaminergic (DA) and hypothalamic-pituitary-adrenal systems. The aim of the present study was to investigate the joint effect of genetic polymorphisms coding for DA catabolism and glucocorticoid receptor (GR, NR3C1) on brain functioning. The study group (90 right-handed white Caucasian healthy individuals) underwent functional magnetic resonance imaging experiments to examine blood oxygenation level dependent (BOLD) response during a WM task with varying cognitive load (1-, 2- and 3-back). We have also examined skin conductance response (SCR) during the WM task and resting-state cerebral blood flow with continuous arterial spin labelling. The genetic markers of interest included Catechol-O-Methyl-Transferase (COMT) (Met(158)Val) and NR3C1 single-nucleotide polymorphisms (BclI C/G rs41423247, 9β A/G rs6198 and rs1866388 A/G). Haplotype-based analyses showed (i) a significant effect of COMT polymorphism on left anterior cingulate cortex, with greater deactivation in Met carriers than in Val/Val homozygotes; (ii) a significant effect of BclI polymorphism on right dorsolateral prefrontal cortex (DLPFC), with greater activation in G/G carriers than in C carriers and (iii) an interactive effect of BclI (G/G) and COMT (Met/Met) polymorphisms, which was associated with greater activation in right DLPFC. These effects remained significant after controlling for whole-brain resting-state blood flow. SCR amplitude was positively correlated with right DLPFC activation during WM. This study demonstrated that GR and COMT markers exert their separate, as well as interactive, effects on DLPFC function. Epistasis of COMT and BclI minor alleles is associated with higher activation, suggesting lower efficiency, of DLPFC during WM.

Glucocorticoid receptor and molecular chaperones in the pathogenesis of adrenal incidentalomas: potential role of reduced sensitivity to glucocorticoids

Glucocorticoid (GC) sensitivity depends on glucocorticoid receptor (GR) and heat shock proteins (Hsps). We investigated whether common GR genes (ER22/23EK, N363S, Bcl I, and 9β) and adrenocorticotropin receptor promoter polymorphisms influence susceptibility for unilateral adrenal incidentaloma (AI), plus GR and Hsp expression in tumorous (n = 19), peritumorous (n = 13) and normal adrenocortical (n = 11) tissues. Patients (n = 112), population-matched controls (n = 100) and tumor tissues (n = 32) were genotyped for these polymorphisms. Postdexamethasone serum cortisol was higher in patients (p < 0.001). GR gene variants, larger allele of Bcl I (odds ratio [OR] 2.9; 95% confidence interval [CI] 1.7-5.1; p < 0.001] and minor allele of 9β (OR 3.0; 95% CI 1.6-5.7; p < 0.001) were independent predictors of AI. In patients, the first allele is linked with larger tumors (p = 0.002) and the latter with higher postdexamethasone cortisol levels (p = 0.025). Both allele carriers had lesser waist circumference (p = 0.02), similar adrenocorticotropin and higher basal (p = 0.024) and postdexamethasone cortisol concentrations (p < 0.001). Tumorous and constitutional genotypes were similar. GR-D is the major receptor isoform in normal adrenal cortex by Western blotting. Loss of other receptor isoforms, decrease in immunostaining for GR (p < 0.0001), underexpression of chaperones (p ≤ 0.01) and the presence of inducible Hsp70 were found in adenomas. In conclusion, GR gene variants, C allele of Bcl I and minor allele of 9β, are associated with AIs. Their concurrent presence in patients reduces GC sensitivity. Normal adrenal cortex preferentially expresses GR-D. In adenomas, the lack of other GR isoforms and underexpression of heat shock proteins perhaps permanently impair GC signaling, which could promote dysregulated cortisol production and tumor growth. The innate GC sensitivity probably modifies these effects.

Glucocorticoid receptor BclI polymorphism associates with immunomodulatory response to stress hormone in human peripheral blood mononuclear cells

Glucocorticoid receptor (GR) variants have been found to be associated with stress-related disorders. Our previous in vivo study revealed that the CC allele of GR BclI single-nucleotide polymorphism (SNP) was more common in the high-stress group, which had lower levels of both regulatory T cells (Treg) and Th1 cytokine. The current study was to investigate the associations between GR BclI polymorphism and immunomodulatory response to stress hormone in vitro in human peripheral blood mononuclear cells (PBMC). Blood samples were collected from 18 normal volunteers including 9 subjects with BclI polymorphism GG allele and 9 with wild-type (WT) CC allele. PBMC were cultured with 10(-8) m dexamethasone (DEX), which mimics the plasma cortisol level observed during periods of psychological stress for 24 h and 11 days. Gene expressions of transcription factors, stress hormone and cytokine receptors were analysed by real-time RT-PCR. FoxP3 mRNA was significantly altered in the BclI WT (decreased at 24 h and increased at 11 days) but not in the GG allele. GR mRNA was up-regulated at 24 h and down-regulated at 11 days in CC alleles (P < 0.01 and P < 0.05), rather than in GG alleles. The expression of β-2 adrenergic receptor (β2AR) was increased at 24 h in both CC and GG alleles (P < 0.01 and P < 0.001), but decreased significantly at 11 days in only GG alleles. Expression of T-bet and GATA-3 was altered simultaneously in 24-h culture with DEX from both groups. The BclI polymorphism of GR identifies different immunomodulatory responses to corticosteroids, which may explain, at least in part, the variability in individual sensitivity to stressors.

Clinical and biochemical impact of BCL1 polymorphic genotype of the glucocorticoid receptor gene in patients with adrenal incidentalomas

BACKGROUND

Adrenal incidentaloma (AI) is a common clinical problem. Subtle hormonal abnormalities are present in a substantial proportion of patients. BCL1 gene polymorphism of the glucocorticoid receptor (GR) is associated with increased sensitivity to glucocorticoid action. The genotype- phenotype associations of this polymomorphism in patients presenting with AI has not been extensively investigated.

AIM

A cross-sectional study in secondary/tertiary care centers.

SUBJECTS/METHODS

Ninety-five subjects with AI were genotyped for the BCL1 GR gene polymorphism. Patients underwent an oral glucose tolerance test and a dexamethasone suppression test (DST). The presence of subclinical hypercortisolism, features of metabolic syndrome, and osteoporosis/ osteopenia were also assessed.

RESULTS

No significant differences in markers of adrenal function between BCL1 carriers and non-carriers were revealed. Also, no difference was found in the features of metabolic syndrome, as well as in bone metabolism and density between these 2 groups. However, DST suppressor patients belonged more frequently to the BCL1 carriers group (41 out of 69 patients, 59.4% vs 9 out of 26 patients, 34.6%, p=0.0039), had smaller total adenoma size (2.4±0.2 cm vs 3.5±0.4 cm, p=0.04), and lower incidence of bilateral adrenal masses (18.8% vs 46.2%, p=0.01).

CONCLUSIONS

AI patients who also carry the polymorphic BCL1 variant exhibit smaller size adrenal nodules. Those AI patients with complete DST suppression had a higher incidence of the polymorphic BCL1 variant. However, this study failed to demonstrate any significant impact of BCL1 GR polymorphism on the frequency of cortisol-dependent co-morbidities in patients with AI.

Glucocorticoid receptor gene polymorphism and juvenile idiopathic arthritis

BACKGROUND

The glucocorticoid receptor gene (NR3C1) has been suggested as a candidate gene affecting juvenile idiopathic arthritis (JIA) course and prognosis. The purpose of this study is to investigate the glucocorticoid receptor gene BclI polymorphism (rs41423247) in JIA patients, the gene's role in susceptibility to juvenile idiopathic arthritis, and its associations with JIA activity, course and bone mineralization.

METHODS

One hundred twenty-two Caucasian children with JIA and 143 healthy ethnically matched controls were studied. We checked markers of clinical and laboratory activity: morning stiffness, Ritchie Articular Index (RAI), swollen joint count (SJC), tender joint count (TJC), physician's visual analog scale (VAS), hemoglobin level (Hb), leukocyte count (L), platelet count (Pl), Westergren erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), albumin, DAS and DAS28. Bone mineralization was measured by dual-energy X-ray absorptiometry (DXA) of lumbar spine L1-L4. Assessments of bone metabolism included osteocalcin, C-terminal telopeptide (CTT), parathyroid hormone (PTH), total and ionized calcium, inorganic phosphate and total alkaline phosphatase (TAP). BclI polymorphism was genotyped by polymerase chain reaction restriction fragment length polymorphism.

RESULTS

No association was observed between glucocorticoid receptor gene polymorphism and the presence or absence of JIA. In girls with JIA, the presence of the G allele was associated with an unfavorable arthritis course, a younger age of onset of arthritis (p = 0.0017), and higher inflammatory activity. The higher inflammatory activity was demonstrated by the following: increased time of morning stiffness (p = 0.02), VAS (p = 0.014), RAI (p = 0.048), DAS (p = 0.035), DAS28 (p = 0.05), Pl (p = 0.003), L (p = 0.046), CRP (p = 0.01). In addition, these patients had bone metabolism disturbances as follows: decreased BA (p = 0.0001), BMC (p = 0.00007), BMD (0.005) and Z score (p = 0.002); and higher levels of osteocalcin (p = 0.03), CTT (p = 0.036), TAP activity (p = 0.01) and ionized calcium (p = 0.017). In boys with JIA, no significant differences were observed related to the polymorphic alleles or genotypes.

CONCLUSIONS

We suggest that G allele and the GG genotype of the glucocorticoid receptor gene BclI polymorphism contribute to an unfavorable course and low bone mineral density in girls with JIA.

Influence of Bcl-1 Gene Polymorphism of Glucocorticoid Receptor Gene (NR3C1, rs41423247) on Blood Pressure, Glucose in Northern Indians

Glucocorticoids and its receptor are known to be involved in the dysregulation of hormone and lipid levels. Therefore, we evaluated the association of Bcl1 gene polymorphism of glucocorticoids receptor (GCR) gene variant with hormone and lipid levels in Northern Indians obese. A total of 435 obese and non-obese age matched subjects were included in the case-control study. Lipid and hormonal levels were estimated using standard protocols. Analysis of +646 C>G NR3C1 gene polymorphism was done using PCR-RFLP. The frequencies of GR Bcl1, C>G genotypes and alleles did not differ significantly (P > 0.05) between obese and non-obese. The +646 G allele carriers had higher waist to hip ratio, blood pressure, insulin and glucose levels than non-carriers in obese subjects while diastolic blood pressure and glucose in non-obese. The NR3C1, +646 C>G polymorphism did not associate with obesity. However, the GG genotype may modulate blood pressure, blood glucose and hormonal levels in northern Indians.

BclI glucocorticoid receptor polymorphism and smoking in the general population

We studied the hypothesis that the BclI polymorphism of the glucocorticoid receptor gene is associated with an increased probability of being a (heavy) smoker and a decreased ability to quit smoking. The study cohort consisted of all subjects in the Rotterdam Study, a Dutch population-based cohort of people aged 55 years and older, for whom BclI genotyping and smoking status at baseline were available. In prospective analyses, the smoking status was reassessed during three additional examination rounds. Logistic regression analysis was used to study the association between BclI polymorphism and being a smoker or a heavy smoker at baseline. Furthermore, the relationship between BclI polymorphism and incident smoking cessation was tested with Cox proportional hazards analysis within those who smoked at baseline. In total, 6358 subjects were included in the study. The presence of a G-allele was not associated with current smoking at baseline [odds ratio (OR) = 0.96, 95%confidence interval (CI): 0.85-1.09] or with the incidence of smoking cessation during follow-up [hazard ratio (HR) = 0.98, 95%CI: 0.80-1.19]. Within current smokers, having a G-allele was not significantly associated with the risk of being a heavy smoker when measured by pack-years smoked (OR = 1.07, 95%CI: 0.85-1.35) or daily consumption of tobacco (OR = 1.10, 95%CI: 0.88-1.37). We were not able to replicate the earlier findings indicating that the proportion of current smokers is lower among carriers of the CC-genotype of the BclI glucocorticoid receptor. Furthermore, the BclI glucocorticoid receptor polymorphism did not predict the incidence of smoking cessation in the general elderly population.

No association of glucocorticoid receptor polymorphisms with asthma and response to glucocorticoids

PURPOSE

Glucocorticoids are the most effective anti-inflammatory drugs in asthma therapy. They act via receptors localized in target cells that after activation by glucocorticoids may affect expression of inflammatory genes thus reducing inflammation in asthma. However, 10-20% of patients, particularly with severe, difficult-to-treat asthma may not respond well to glucocorticoids and remain symptomatic even after being treated with high doses of inhaled or systemic glucocorticoids. Therefore, we investigated if polymorphisms known to affect expression or function of the glucocorticoid receptor may be responsible for lower efficacy of steroid therapy and the need to use high doses of inhaled drug.

MATERIAL AND METHODS

We analyzed 113 pediatric patients in age from 6 to 18 with diagnosed asthma, including 54 children with severe, difficult-to-treat asthma. The diagnosis was based on clinical manifestation, a lung function test, increased IgE level and positive skin prick tests. We also analyzed 123 healthy control subjects. The polymorphisms were genotyped with the use of PCR-RFLP method. Linkage disequilibrium analysis was performed using Haploview.

RESULTS

We did not observe any significant differences between asthmatic and healthy children for any of the polymorphisms analyzed. Weak linkage between two of the four polymorphisms studied: rs41423247 and rs6195 (D'=1.0; LOD=2.91, r2=0.044) was found in linkage disequilibrium analysis. We did not find any association of GR polymorphisms with the dose of inhaled glucocorticoids needed to achieve asthma control in the group of patients.

CONCLUSION

The results may suggest that studied polymorphisms of the GR gene are not associated with asthma susceptibility and do not influence response to inhaled glucocorticoids in our sample.

Pharmacogenetics of the neurodevelopmental impact of anticancer chemotherapy

Pharmacogenetics holds the promise of minimizing adverse neurodevelopmental outcomes of cancer patients by identifying patients at risk, enabling the individualization of treatment and the planning of close follow-up and early remediation. This review focuses first on methotrexate, a drug often implicated in neurotoxicity, especially when used in combination with brain irradiation. The second focus is on glucocorticoids that have been found to be linked to adverse developmental effects in relation with the psychosocial environment. For both examples, we review how polymorphisms of genes encoding enzymes involved in specific mechanisms of action could moderate adverse neurodevelopmental consequences, eventually through common final pathways such as oxidative stress. We discuss a multiple hit model and possible strategies required to rise to the challenge of this integrative research.

Salivary cortisol as a biomarker in stress research

Salivary cortisol is frequently used as a biomarker of psychological stress. However, psychobiological mechanisms, which trigger the hypothalamus-pituitary-adrenal axis (HPAA) can only indirectly be assessed by salivary cortisol measures. The different instances that control HPAA reactivity (hippocampus, hypothalamus, pituitary, adrenals) and their respective modulators, receptors, or binding proteins, may all affect salivary cortisol measures. Thus, a linear relationship with measures of plasma ACTH and cortisol in blood or urine does not necessarily exist. This is particularly true under response conditions. The present paper addresses several psychological and biological variables, which may account for such dissociations, and aims to help researchers to rate the validity and psychobiological significance of salivary cortisol as an HPAA biomarker of stress in their experiments.

Response to prednisone in relation to NR3C1 intron B polymorphisms in childhood nephrotic syndrome

The variation in time required to obtain cessation of proteinuria in children with nephrotic syndrome (NS) represents one aspect of the variations shown by these children in response to glucocorticoid (GC) treatment. Polymorphism of the GC receptor gene (NR3C1) has been postulated as one factor that would partially explain differences in both the clinical presentation and the reaction to treatment in GC-treated diseases. We genotyped 118 children diagnosed with NS who initially responded to oral GC treatment [steroid-responsive nephrotic syndrome (SRNS) group] and 136 healthy children for three intron B single nucleotide polymorphisms of NR3C1, namely Bcl I (C/G), rs33389 (C/T) and rs33388 (A/T). In the SRNS group, we performed a three-marker haplotype analysis of NR3C1 in relation to the response to prednisone, represented as time to proteinuria resolution (TPR) as categorical and ordinal variable.

RESULTS

The distribution of individual polymorphisms and three-marker haplotypes was similar in healthy children and SRNS patients (all p values >0.05). The GTA haplotype was associated with a higher GC sensitivity, as determined by TPR, and was found to be more prevalent in early (response <or=7 days) than late (response >7 days) prednisone responders (27.7 vs. 14.5%, hap-score = -2.22, p = 0.05 adjusted for biopsy results). These results are in agreement with those reported earlier on an association of intron B haplotypes with GC sensitivity. The distribution of GC polymorphisms among the residents of north-eastern Poland was also determined.

A common intron 2 polymorphism of the glucocorticoid receptor gene is associated with insulin resistance in men

OBJECTIVE

Clinical similarities between the metabolic syndrome and Cushing's syndrome have led to speculation of genetic association between them. The Bcl1 polymorphism in intron 2 of the glucocorticoid receptor (GR) gene has been associated with insulin resistance/hyperinsulinaemia. Our objective was to test the association of rs2918419, a T-->C single nucleotide change in intron 2 downstream of the Bcl1 locus, with components of the metabolic syndrome and its interaction with the Bcl1 locus.

DESIGN AND METHODS

We genotyped a subsample of 325 White subjects (116 men) in the Newcastle Heart Project (NHP), a population-based study in north-east England. Gender-specific statistical analysis by stepwise backward multiple regression was performed to test the association of allele status with adiposity, glucose and insulin responses to oral glucose tolerance test (OGTT), fasting lipids and blood pressure.

RESULTS

Minor allele frequency was 0.14 for rs2918419 and 0.39 for the Bcl1 polymorphism. rs2918419 was associated with higher fasting insulin concentration and insulin resistance in men but not in women. Contrary to earlier studies, the Bcl1 polymorphism on its own was not associated with insulin resistance/hyperinsulinaemia in either gender. Subjects carrying variant rs2918419 alleles also had variant alleles at the Bcl1 locus. In men, but not women, Bcl1 variant alleles on a background of rs2918419 wild-type alleles associated with lower fasting insulin compared to wild-type alleles at both loci or variant alleles at both loci.

CONCLUSIONS

We report that rs2918419 was linked with hyperinsulinaemia and insulin resistance in men. Carrying Bcl1 variant alleles without rs2918419 was not associated with hyperinsulinaemia/insulin resistance. Previous reports of the association of Bcl1 polymorphism with obesity-related characteristics may reflect linkage disequilibrium with rs2918419.

Corticosteroid receptor polymorphisms: determinants of vulnerability and resilience

Why some individuals thrive and others break down under similar adverse conditions, is a central question in the neuroendocrinology of stress related psychopathology. The brain mineralocorticoid (MR) and glucocorticoid receptors (GR) operate in balance to coordinate behavioural, autonomic and neuroendocrine response patterns involved in homeostasis and health. Genetic variants of both the MR and GR have been functionally characterized. The four GR-gene single nucleotide polymorphisms (SNPs) (ER22/23EK (allele frequency: 3%), N363S (4%), BclI (37%), A3669G (15%)) and the two MR-gene SNPs (-2 G/C (50%), MR-I180V (11%)) showed in vitro changes in transactivational capacity, or affect stability of the mRNA (GR exon 9beta A3669G). All of these MR-and GR-SNPs change the regulation of the hypothalamus-pituitary-adrenal (HPA) axis at different levels including basal level (-2 G/C), dexamethasone induced negative feedback (ER22/23EK, N363S, BclI, 9beta A3669G) or following a psychosocial stress test (Trier Social Stress Test (TSST); all of the MR-and GR-SNPs). Importantly, the MR-I180V increased autonomic output and enhanced cortisol secretion during the TSST. Recently, several of these MR-and GR-variants have been found associated with psychopathology (depression, bipolar disorder). These data provide evidence that dysregulation of MR and GR are causative in the pathogenesis of depression and that these MR-and GR-gene variants are part of the genetic make up that determines individual stress-responsivity and coping style, affecting vulnerability to disease.

Sex specific associations between common glucocorticoid receptor gene variants and hypothalamus-pituitary-adrenal axis responses to psychosocial stress

BACKGROUND

Alterations in glucocorticoid (GC) signaling have been associated with a number of psychiatric disorders. Genetic variation of the glucocorticoid receptor (GR) might be one of the factors underlying susceptibility to stress related disease.

METHODS

We investigated 206 healthy subjects and assessed associations between four common GR gene (NR3C1) polymorphisms (ER22/23EK, N363S, BclI, 9beta) and hypothalamic-pituitary-adrenal (HPA) axis responses to psychosocial stress (Trier Social Stress Test, TSST) and glucocorticoid sensitivity measured by a dexamethasone suppression test (DST).

RESULTS

Male 9beta AG carriers displayed the highest adrenocorticotropic hormone (ACTH) and total cortisol TSST responses (for ACTH: main effect genotype p = .02) whereas male BclI GG carriers showed diminished responses. Remarkably, the BclI GG genotype in women (all using oral contraceptives) was associated with the highest total cortisol TSST responses, resulting in a significant sex by genotype interaction (p = .03). Following the DST, male 9beta AG carriers had elevated ACTH levels (sex by genotype interaction p = .03).

CONCLUSIONS

We observed significant sex specific associations between GR gene polymorphisms and HPA axis responses to psychosocial stress as well as GC sensitivity. These findings support the relevance of GR gene polymorphisms in HPA axis regulation. Genetic variations of the GR might constitute a risk factor in development of HPA axis related disorders.

Association between the BclI glucocorticoid receptor polymorphism and smoking in a sample of patients with obstructive airway disease

Glucocorticoids seem to mediate the effect of stimulant drugs such as nicotine. Several studies have pointed to an association between the BclI polymorphism in the glucocorticoid receptor gene and increased glucocorticoid effects. We analysed the association of smoking behaviour and the BclI polymorphism using a case-control design within the framework of a larger pharmacogenetic study. A total of 327 Caucasian patients with asthma or chronic obstructive pulmonary disease from 39 German general practices gave informed consent to take part in the study. They filled in questionnaires concerning their smoking behaviour and were genotyped for the BclI polymorphism. The genotype frequencies for non-smokers (n = 251; CC, 0.42; CG, 0.46; GG, 0.12) as well as for smokers (n = 76; CC, 0.29; CG, 0.55; GG, 0.16) were consistent with the Hardy-Weinberg equilibrium. The proportion of smokers was significantly lower among carriers of the CC-genotype (22/127 = 17%) compared with carriers of the G-allele (54/200 = 27%; chi2 = 4.08; P = 0.04). Within the group of smokers, the proportion of heavy smokers (> 19 cigarettes/day; median) was reduced in C-homozygous patients when compared with carriers of the G-allele (7/22 = 32% versus 31/54 = 57%; chi2 = 4.09; P = 0.04). Stepwise logistic regression analysis also pointed to an association between the CC-genotype and a reduced probability of being a smoker (odds ratio = 0.55; 95% confidence interval = 0.30-1.00; P = 0.05) controlling for other predictors. In summary, this study provides evidence that the BclI polymorphism might play a role in the maintenance and severity of nicotine dependence.

High anticipatory stress plasma cortisol levels and sensitivity to glucocorticoids predict severity of coronary artery disease in subjects undergoing coronary angiography

Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and/or increased sensitivity of peripheral tissues to glucocorticoids may be associated with the dysmetabolic syndrome and its cardiovascular sequelae. In this prospective pilot clinical study, we examined possible associations between HPA axis activity and severity of cardiovascular disease. We measured morning serum cortisol and intima media thickness (IMT) of carotid and femoral arteries in 105 subjects before undergoing coronary angiography for suspected coronary artery disease (CAD). In a randomly selected 46 of these subjects, we obtained late afternoon and morning cortisol levels (after ultralow-dose dexamethasone [0.25 mg] treatment) and determined their genotype for the Bcl1 polymorphism of the glucocorticoid receptor gene, which has been associated with increased sensitivity to glucocorticoids. There was significant association between morning preangiography cortisol levels and the number of vessels with severe stenosis in the angiography, independently of age or sex (P = .002), and a trend for a positive correlation between morning cortisol and the IMT of the femoral artery (P = .057). Bcl1 G allele homozygotes had a significantly higher carotid IMT (P = .005) and a nonsignificant tendency for higher waist-hip ratio (P = .059). Hyperactivity of the HPA axis in anticipation of a stressful procedure, such as angiography, may be an index of CAD severity. Chronic HPA axis hyperreactivity combined with tissue hypersensitivity to glucocorticoids may contribute to more severe atherosclerosis and CAD.

A Brief Update of Glucocorticoid Receptor Variants and Obesity Risk

Excess body fat, obesity, is one of the most common disorders in clinical practice. Obese individuals are at increased risk for physical ailments, such as type 2 diabetes, coronary heart disease, hypertension, and several types of cancer. The location of the body fat is a major determinant of the degree of excess morbidity and mortality due to obesity. More specifically, the amount of subcutaneous truncal or abdominal fat, and the amount of visceral fat located in the abdominal cavity independently predicts obesity-related adverse health outcomes. The obesity gene map shows putative loci on all chromosomes except Y. More than 300 genes, markers, and chromosomal regions have been associated or linked with human obesity phenotypes. These genes can be divided into two broad categories: (a) rare gene variants that have a strong influence, and (b) common gene variants that have a weaker influence on obesity phenotypes. Studies in humans have suggested a positive association between obesity, hypertension, and insulin resistance, with alleles at the glucocorticoid receptor gene. In this article, we will estimate the risk by which such gene polymorphism mediates a role in obesity.

Detection of the Bcl I polymorphism of the glucocorticoid receptor gene by single-tube allele-specific polymerase chain reaction

The Bcl I polymorphism of the glucocorticoid receptor gene, recently identified as an intronic C to G change 646 nucleotides downstream of exon 2, has been associated with increased sensitivity to glucocorticoids and its potential relevance in metabolic disturbances and in various disorders has been extensively investigated. In the present study, we designed a single-tube allele-specific polymerase chain reaction for genotyping this polymorphism in peripheral blood DNA samples. When the Bcl I polymorphism was detected with this novel method in a cohort of 247 healthy subjects, the observed genotype distribution matched the Hardy-Weinberg equilibrium (100 subjects homozygous for the wild-type, 124 heterozygous and 23 homozygous for the mutant allele). In 50 randomly selected subjects the Bcl I polymorphism was also determined using a traditional restriction fragment length polymorphism technique and DNA sequencing, and the results showed 100% coincidence with those obtained by our novel method. The method proved to be more rapid and less labour-intensive compared to currently used techniques, and it avoided the use of extensive instrumentals. We assume that this novel method may have a broad utility in clinical and molecular epidemiological studies aimed to elucidate the impact of the Bcl I polymorphism of the glucocorticoid receptor gene either on metabolic disturbances, or various disorders, including cancer treatment and hormone substitution therapies.

Corticosteroid receptor genetic polymorphisms and stress responsivity

A fundamental question in the neuroendocrinology of stress-related psychopathology is why some individuals flourish and others perish under similar adverse conditions. In this contribution we focus on the variants of mineralocorticorticoid (MR) and glucocorticoid receptors (GR) that operate in balance and coordinate behavioral, autonomic, and neuroendocrine response patterns involved in homeostasis and health. In the GR-gene, three single nucleotide polymorphism (SNPs) have been associated with changes in metabolic profile and cardiovascular parameters: the ER22/23EK with a favorable and the N363S and the Bcl1 with a more adverse profile. Importantly, the N363S and the Bcl1 are found to increase cortisol responses to a psychosocial stressor. As a result, the whole body will suffer from overexposure with possible adverse effects on metabolism, cardiovascular control, immune function, and behavior. Also in the MR gene, variants are being identified that are associated with dysregulated autonomic, behavioral, and neuroendocrine responses. The data suggest that these MR and GR variants contribute to individual differences in resilience and vulnerability to stressors, and that these receptors therefore are potential drug targets for recovery of homeostasis and health.

Genetic Variations in the Glucocorticoid Receptor Gene Are Not Related to Glucocorticoid Resistance in Childhood Acute Lymphoblastic Leukemia

Glucocorticoid sensitivity is an important prognostic factor in pediatric acute lymphoblastic leukemia (ALL). For its antileukemic effect, glucocorticoid binds the intracellular glucocorticoid receptor (GR) subsequently regulating transcription of downstream genes. We analyzed whether genetic variations within the GR gene are related to differences in the cellular response to glucocorticoids.

METHODS

In leukemic samples of 57 children, the GR gene was screened for nucleotide variations using a PCR/single-strand conformational polymorphism sequencing strategy. Data were linked to in vivo and in vitro glucocorticoid resistance.

RESULTS

No somatic mutations were detected in the GR gene coding region, but six polymorphisms (i.e., ER22/23EK, N363S, BclI, intron mutation 16 bp upstream of exon 5, H588H, and N766N) were identified. In 67% of ALL cases, at least one minor allele of these polymorphisms was detected. Although only borderline significant, the incidence for the N363S polymorphism minor allele was higher (12% versus 6%, P = 0.06) and for the ER22/23EK minor allele lower (4% versus 7.6%, P = 0.1) than in a healthy, comparable population. The different genotypes of the polymorphisms were not related to prednisone resistance. In conclusion, polymorphisms but not somatic mutations in the GR gene coding region occur in leukemic blasts of children with ALL. Our data suggest that these genetic variations are not a major contributor for differences in cellular response to glucocorticoids in childhood ALL. The higher incidence of the N363S minor allele and the lower incidence of the ER22/23EK minor allele in our ALL population as compared with a normal population warrants further research.

A psychobiological perspective on genetic determinants of hypothalamus-pituitary-adrenal axis activity

From the perspective of psychobiological stress research we present a brief overview of findings documenting a significant impact of genetic factors on the activity of the hypothalamus-pituitary-adrenal (HPA) axis. Quantitative genetic studies in twins as well as association studies, primarily on polymorphisms in the glucocorticoid receptor gene, are depicted. Recent findings suggest that the collaboration of psychobiology and molecular genetics is a promising interdisciplinary approach that will significantly contribute to the understanding of the mechanisms underlying the link between stress, the HPA axis, and HPA-related clinical states.

Signaling pathways in brain involved in predisposition and pathogenesis of stress-related disease: genetic and kinetic factors affecting the MR/GR balance

Optimal regulation of the stress response is a prerequisite for adaptation, homeostasis, and health. There are two modes of operation in the stress response. First, an immediate response mode mediated by corticotrophin-releasing hormone-1 (CRH-1) receptors that organizes the behavioral, sympathetic, and hypothalamic-pituitary-adrenal (HPA) response to a stressor. Second, a slower mode, which facilitates behavioral adaptation, promotes recovery, and reestablishes homeostasis. Corticosteroid hormones are implicated in both stress system modes. On the one hand, cortisol and corticosterone determine the threshold or sensitivity of the fast responding mode, whereas the very same hormones in high concentrations facilitate termination of the stress response. In the brain, these actions exerted by the corticosteroid hormones are mediated by two distinct nuclear receptor types, that is, mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs). Whereas MRs maintain neuronal homeostasis and limit the disturbance by stress, GRs help to recover after the challenge and to store the experience for coping with future encounters. Imbalance in MR/GR-mediated actions compromises homeostatic processes in these neurons, which is thought to underlie maladaptive behavior and HPA dysregulation that may lead to aberrant metabolism, impaired immune function, and altered cardiovascular control. The balance in MR/GR-mediated actions depends on bioavailability of corticosteroids, access to the receptors, the stoichiometry of co-regulators, and other proteins as well as genetic factors, among which single nucleotide polymorphisms (SNPs) of the GRs are extensively documented. Stress can bias the receptor signaling pathways, changing "good" corticosteroid actions into "bad" ones.

Habituation of cortisol responses to repeated psychosocial stress-further characterization and impact of genetic factors

Although a rapid response habituation to repeated stress exposure is a key characteristic of the hypothalamus-pituitary-adrenal (HPA) axis, several studies document a substantial inter-individual variability of such HPA response patterns. In order to further investigate the individual differences in the habituation of this important neuroendocrine system to psychosocial stress, 54 male twin pairs were exposed to moderate psychosocial stress on three occasions, each exposure separated by a 1-week interval. Additionally, an ACTH(1-24) stimulation test (1 microg) and a dexamethasone suppression test (0.5mg) were performed. Although on average the expected decrease of mean cortisol and ACTH responses across stress exposures was observed, only 52% of the subjects showed this well-documented general decline and almost 16% of the participants even showed a response sensitization across sessions. Furthermore, a weak habituation was related to low cortisol responses to both the first stress exposure as well as the ACTH challenge. Moreover, genetic analyses did not reveal any evidence for a substantial heritability of the individual cortisol response habituation or an association between this habituation and two common polymorphisms in the glucocorticoid receptor gene.

Role of stress in the pathogenesis of the metabolic syndrome

Excess body fat, obesity, is one of the most common disorders in clinical practice. In addition, there is a clustering of several risk factors with obesity, including hypertension, glucose intolerance, diabetes mellitus, and hyperlipidemia, which is observed more frequently than by chance alone. This has led to the suggestion that these represent a single syndrome and is referred to as the Metabolic Syndrome. A growing body of evidence suggests that glucocorticoid secretion is associated with this complex phenotype. Continuously changing and sometimes threatening external environment may, when the challenge exceeds a threshold, activate central pathways that stimulate the adrenals to release glucocorticoids. In this review, we will discuss how such processes mediate a pathogenetic role in the Metabolic Syndrome.

Polymorphisms in Genes Involved in the Corticosteroid Response and the Outcome of Childhood Acute Lymphoblastic Leukemia

BACKGROUND

Considerable variability in sensitivity to corticosteroids (CS) has been observed among individuals with regard to both the natural and synthetic compounds. The role of genetic polymorphisms in modulating CS function, and hence in disease susceptibility, has been extensively analyzed. Their impact on therapeutic response still remains to be explored. The role of cytochrome P450 (CYP) 3A4 in corticosteroid metabolism, and that of the glucocorticoid receptor (NR3C1) in regulation of responsive genes, renders CYP3A4 and NR3C1 polymorphisms as potential candidates for pharmacogenetic analysis.

AIM

The aim of the study was to analyze the role of these polymorphisms in the outcome of a disease treated with CS drugs.

METHODS

Towards this aim we analyzed the CYP3A4-290A/G substitution and three NR3C1 polymorphisms (200G/A, 1220A/G and BclI RFLP) in 222 children with acute lymphoblastic leukemia (ALL) whose treatment protocols, among other components, contained corticosteroid drugs.

RESULTS

The analysis of survival probabilities in relation to the indicated genotypes showed only an association between homozygosity for allele G of the NR3C1 BclI RFLP polymorphism and overall survival (univariate and multivariate hazard ratio [HR] 2.7, 95% confidence interval [CI] 1.0, 7.6 and 5.2, 95% CI 1.4, 18.9, respectively). The association reflects a correlation with disease progression and prognosis, and may vary depending on risk of relapse.

CONCLUSION

A reduction in survival probability in children with ALL was associated with homozygosity for G allele of the NR3C1BclI RFLP polymorphism, particularly in certain patient subgroups. Further analysis is required to replicate this finding and to understand the mechanism underlying the observed association.