NR3C1 Gene Expression Research Articles

Long noncoding RNA GAS5: a novel marker involved in glucocorticoid response.

Glucocorticoids (GCs) exert their effects through regulation of gene expression after activation in the cytoplasm of the glucocorticoid receptor (GR) encoded by NR3C1 gene. A negative feedback mechanism resulting in GR autoregulation has been demonstrated through the binding of the activated receptor to intragenic sequences called GRE-like elements, contained in GR gene. The long noncoding RNA growth arrest-specific transcript 5 (GAS5) interacts with the activated GR suppressing its transcriptional activity. The aim of this study was to evaluate the possible role of GAS5 and NR3C1 gene expression in the antiproliferative effect of methylprednisolone in peripheral blood mononuclear cells and to correlate the expression with individual sensitivity to GCs. Subjects being poor responders to GCs presented higher levels of GAS5 and NR3C1 in comparison with good responders. We suggest that abnormal levels of GAS5 may alter GC effectiveness, probably interfering with the mechanism of GR autoregulation.

Glucocorticoid receptor gene (NR3C1) promoter is hypermethylated in Thai females with major depressive disorder.

Major depressive disorder (MDD) has been associated with the stress response in the brain, which is controlled by the hypothalamic-pituitary-adrenal (HPA) axis. This HPA negative feedback mechanism acts via the activation of glucocorticoid receptor, which is encoded by the NR3C1 gene. The methylation status at the promoter of NR3C1 has been correlated with traumatic experiences in early life, which develop into mental disorder. The aim of this study was to examine the potential associations between the methylation status of NR3C1 promoter, gene expression, blood plasma cortisol levels, and adulthood MDD. The study was conducted with 29 MDD patients (9 males, 20 females) and 33 normal individuals (7 males, 26 females). Bisulfite pyrosequencing on 7 CpG dinucleotides in the region showed significantly higher methylation levels at the CpG7 in MDD patients. When separated by gender, the methylation levels differed significantly in females, but not in males. No significant differences between NR3C1 gene expression level and plasma cortisol levels of MDD patients and normal controls were observed. These data suggest that higher levels of methylation at the NR3C1 promoter may be associated with MDD in a gender-specific manner.

Synaptic plasticity alterations associated with memory impairment induced by deletion of CB2 cannabinoid receptors

In this study, the role of CB2r on aversive memory consolidation was further evaluated. Mice lacking CB2r (CB2KO) and their corresponding littermates (WT) were exposed to the step-down inhibitory avoidance test (SDIA). MAP2, NF200 and synaptophysin (SYN)-immunoreactive fibers were studied in the hippocampus (HIP) of both genotypes. The number of synapses, postsynaptic density thickness and the relation between the synaptic length across the synaptic cleft and the distance between the synaptic ends were evaluated in the HIP (dentate gyrus (DG) and CA1 fields) by electron microscopy. Brain-derived neurotrophic factor (BDNF), glucocorticoid receptor (NR3C1) gene expressions and mTOR/p70S6K signaling cascade were evaluated in the HIP and prefrontal cortex (PFC). Finally, the effects of acute administration of CB2r-agonist JWH133 or CB2r-antagonist AM630 on memory consolidation were evaluated in WT mice by using the SDIA.The lack of CB2r impaired aversive memory consolidation, reduced MAP2, NF200 and SYN-immunoreactive fibers and also reduced the number of synapses in DG of CB2KO mice. BDNF and NR3C1 gene expression were reduced in the HIP of CB2KO mice. An increase of p-p70S6K (T389 and S424) and p-AKT protein expression was observed in the HIP and PFC of CB2KO mice. Interestingly, administration of AM630 impaired aversive memory consolidation, whereas JWH133 enhanced it. Further functional and molecular assessments would have been helpful to further support our conclusions.These results revealed that CB2r are involved in memory consolidation, suggesting that this receptor could be a promising target for developing novel treatments for different cognitive impairment-related disorders.

Effect of psychosocial stress on FKBP5 and NR3C1 gene expression in healthy young men

Stress diseases such as affective disorders are often characterized by a disturbed regulation of the hypothalamus-pituitary-adrenocortical (HPA) axis. This dysregulation can be explained by an impaired function of the receptors involved in the HPA-axis regulation, for example, the glucocorticoid receptors (GR). The regulation process of the HPA axis and the GR function are influenced by several genes, for instance by NR3C1 coding for the GR and also by FKBP5, a co-chaperone in the GR-complex. Binder et al. showed that common polymorphisms in FKBP5 are associated with increased FKBP5 protein expression as well as correlation between cortisol levels and peripheral blood FKBP5 mRNA expression . Regarding the effects of FKPB5 genotypes on psychosocial stress reaction, Ising and colleagues tested healthy subjects with the Trier Social Stress Test, a standardized paradigm to induce psychosocial stress . Subjects homozygous for any of the FKBP5 variants showed an incomplete normalization of the stress induced cortisol secretion.Recent studies demonstrated that FKBP5 and NR3C1 are involved in the endocrine stress reaction. Therefore, we expected changes of FKBP5 and NR3C1 mRNA expression in peripheral blood after exposure to a psychosocial stress situation. To address this, we performed a pilot study where we tested six healthy young men without history of psychiatric or severe somatic disorders and applied the trier social stress test (TSST). Before and after two consecutive TSSTs, we took blood samples with a venous catheter in order to measure ACTH and cortisol in plasma and mRNA expression of the candidate genes in peripheral blood. Blood cells were stabilized using PAXgene tubes, and gene expression was processed by qPCR.Briefly after the psychosocial stress the stress hormones ACTH and cortisol increased whereas the reaction to the second TSST was lower suggesting a habituation effect. These endocrine stress responses were followed by an alteration in FKBP5 gene expression, further underlining the importance of this gene for the neuroendocrine stress reaction. NR3C1 mRNA levels did not change after the TSST.Our preliminary data indicate an effect of psychosocial stress on the FKBP5 mRNA levels. Further research with larger samples sizes is required to replicate and extend these results.

Effect of psychosocial stress on FKBP5 and NR3C1 gene expression in healthy young men

Stress diseases such as affective disorders are often characterized by a disturbed regulation of the hypothalamus-pituitary-adrenocortical (HPA) axis. This dysregulation can be explained by an impa...

Dietary protein restriction and excess of pregnant German Landrace sows induce changes in hepatic gene expression and promoter methylation of key metabolic genes in the offspring

Maternal nutrition during gestation has important effects on offspring gene expression mediated by DNA methylation. In order to evaluate the effect of restricted and excess protein intake during gestation, hepatic gene expression and DNA methylation of key metabolic genes NR3C1, PPARα, HMGCR, PGC1α, INSR and CYP2C34 were investigated. Liver samples of German Landrace offspring were collected at Gestational Day 95, at birth, at weaning and from finisher pigs. Gene expression in foetal liver revealed significant differences between the control group (CO) and the low-protein group (LP) in HMGCR (P<.0001), INSR (P=.0003), NR3C1 (P=.020) and PGC1α (P=.003). At birth INSR (P=.032), PPARα (P=.0006) and CYP2C34 (P<.0001) showed significant differences between LP and CO. CYP2C34 was significantly increased in the high-protein group (HP) compared to CO (P=.001). At weaning, INSR was significantly higher expressed in LP than in CO (P=.018). HMGCR showed a significant decrease of transcript amount in HP compared to CO (P=.0006). Furthermore, we studied the question whether gene expression differences between distinct diet groups are a result of differential DNA methylation status. CpG sites in the 5′-flanking region of CYP2C34 showed a significant positive correlation with transcript amount in LP (nt −137: R=0.67, P<.0001; nt −112: R=0.54, P=.003). In NR3C1 methylation, differences in the CpG island were negatively correlated with gene expression data in LP (R=−0.34, P=.032). The mean of methylation of PPARα over CpG sites from nt −220 to −11 was significantly increased in the LP group compared with CO (P=.043). These data suggest an influence of DNA methylation in nutrient-dependent transcriptional regulation of NR3C1, PPARα and CYP2C34.

Low Expression of Nuclear Glucocorticoid Receptor Gene NR3C1 in Newly Diagnosed Myeloma Correlates with Inferior Prognosis and Is Rescued by Thalidomide

Abstract 988 Background:Dexamethasone remains a key component of myeloma therapy. We previously showed that expression levels of the nuclear glucocorticoid receptor NR3C1 were associated with OS and PFS in patients treated on Total Therapy 3 (TT3). Post relapse survival (PRS) is an important component of OS following initial PFS. In this study we investigate the effect of NR3C1 expression levels at baseline (BL) and at relapse (RL) on OS, PFS and PRS for patients treated on Total Therapy 2 (TT2). Methods:TT2 was a randomized phase-III trial evaluating the impact of the up-front addition of thalidomide (T) to a multi-agent chemotherapy and high-dose melphalan program supported by tandem autotransplants. Between October 1998 and February 2004, 668 patients with newly diagnosed progressive or symptomatic multiple myeloma up to age 75 were enrolled. 351 patients had gene expression profiling (GEP) obtained at BL and 121 had GEP data obtained at RL. There was no significant difference in OS, PFS or PRS between patients with or without GEP data at BL or at RL. This analysis is based on the cohort of patients with GEP data with a cut-off date of April 22, 2011. OS and PFS were measured from the time of initiation of protocol-based therapy while PRS was measured from the initiation of salvage therapy. Results:Among patients randomized to the control arm (-T), OS improved progressively with the transition from lower to middle to upper NR3C1 tertiles. No such difference was noted in the experimental group with T (+T). Examining treatment arms within NR3C1 expression tertiles showed significant benefit from T in both OS and PFS among patients presenting with lower tertile expression; in the mid tertile, this effect was limited to PFS while such benefit was absent in the top-tertile subgroup. Multivariate analysis accounting for the interaction between NR3C1 expression and T showed that randomization to T and lower tertile NR3C1 expression reduced the hazard of death, while high risk designation by GEP, elevated B2M, elevated LDH, cytogenetic abnormalities and MS subgroup designation all conveyed a higher HR for death. With an overall median PRS of 3.0 years, there was no difference related to the initial treatment randomization or between baseline NR3C1 expression levels. In the context of treatment arms in patients randomized to -T, high- and mid-tertile NR3C1 levels at baseline dramatically improved PRS; such an effect was not observed in +T. We next investigated the implications of NR3C1 levels at relapse on PRS, revealing a significant shortening of PRS with transition from top- to mid- to low-tertile expression. Patients maintaining low NR3C1 levels also at relapse had the shortest PRS, followed by those who lost mid to high expression levels of NR3C1 at relapse, while those with higher than low-tertile levels at relapse enjoyed the longest PRS regardless of NR3C1 expression levels at baseline. Multivariate analysis including data from baseline and relapse as well as accounting for interaction between NR3C1 and T identified GEP high risk status at relapse as the only feature linked to inferior PRS whereas upper tertile expression of NR3C1 conveyed improved PRS. Conclusion:Low expression of NR3C1 at baseline is associated with poor PFS and OS in patients treated on the control arm of TT2. This confirms our previously reported findings in TT3. Addition of T overcomes the poor OS in patients with low NR3C1 expression. Low expression of NR3C1 at relapse correlated with poor PRS. This study indicates that patients with low NR3C1 expression levels at baseline benefit from the addition of T and offers a scientific rationale for NR3C1 gene expression level testing. Future trials, that include thalidomide or lenalidomide in their treatment regimen, will have to take NR3C1 expression levels into account. Disclosures:Shaughnessy:Myeloma Health, Celgene, Genzyme, Novartis: Consultancy, Employment, Equity Ownership, Honoraria, Patents & Royalties. Barlogie:Celgene: Consultancy, Honoraria, Research Funding; IMF: Consultancy, Honoraria; MMRF: Consultancy; Millennium: Consultancy, Honoraria, Research Funding; Genzyme: Consultancy; Novartis: Research Funding; NCI: Research Funding; Johnson & Johnson: Research Funding; Centocor: Research Funding; Onyx: Research Funding; Icon: Research Funding.

Gene Expression of Hepatic Glucocorticoid Receptor NR3C1 and Correlation with Plasmatic Corticosterone in Italian Chickens

This study examined breed-specific stress-related hormonal and gene expression profiles in three Italian chicken breeds (Valdarnese Bianca, Bionda Piemontese, Robusta Maculata) reared in controlled conditions. Glucocorticoids work through the glucocorticoid receptor (GR), which modulates target genes transcription. We investigated breed-specific changes in corticosterone (ELISA) and GR expression. GR mRNA levels were analyzed using one-tube, two-temperature real-time PCR for absolute quantification of the gene expression by the standard curve method. Our results show high expression of GR in hepatic tissue. Significant effect of the breed was recorded for plasma corticosterone concentration: Valdarnese Bianca 3.35 ng/mL, Bionda Piemontese 1.73 ng/mL, Robusta Maculata 2.02 ng/mL. Breed specific gene expression has been recorded with a GR ranging from 1.12E+04 (Robusta Maculata) to 1.00E+05 (Bionda Piemontese) mRNA copy number/100 ng total RNA. Negative correlation was found between gene expression and blood corticosterone level.

Human Glucocorticoid Receptor α Gene (NR3C1) Pharmacogenomics: Gene Resequencing and Functional Genomics

The human glucocorticoid receptor alpha (GRalpha) is a nuclear hormone receptor that regulates multiple physiological and pathophysiological processes. There are large variations in both physiological and therapeutic response to glucocorticoids. Multiple previous studies suggested that genetic polymorphisms in GRalpha (NR3C1) might play an important role. The aim of the study was to identify and determine the functional implications of common genetic variation in NR3C1. We resequenced the NR3C1 gene using 240 DNA samples from four ethnic groups, followed by functional characterization of the effects of selected polymorphisms. A total of 108 polymorphisms were identified in GRalpha, including nine nonsynonymous coding single nucleotide polymorphisms (cSNPs) and four synonymous cSNPs with a minor allele frequency greater than 5%. Functional studies showed that SNPs encoding Phe(65)Val and Asp(687)Glu displayed slightly increased levels of protein compared with WT, and Asp(687)Glu also caused increased GRalpha receptor number. In addition, Ala(229)Thr and Ile(292)Val showed slightly decreased ligand binding affinity in COS-1 cells. A genotype-phenotype association study of NR3C1 gene expression in 240 lymphoblastoid cell lines identified one SNP, Cm746T>C, located 5'-upstream of noncoding exon 1C, and one haplotype, Cm237delC/Cm238C>T/Cm240G>C in exon 1C of the gene that were associated with GRalpha mRNA expression and a trend with GRalpha number. These results represent a step toward understanding the functional role of common sequence variation in the GRalpha gene (NR3C1) and the potential application of those SNPs in translational studies.