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1.
Int. j. morphol ; 38(2): 400-405, abr. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1056454

RESUMO

Accumulating evidence from preclinical and clinical studies indicates prenatal exposure to stress or excess glucocorticoids can affect offspring brain. Glucocorticoid receptor (GR) is an important target of glucocorticoid. Therefore the aim of the present study was to investigate the expression of GR in prenatally stressed adult offspring and the relationship between GR expression and behavior in offspring. Pregnant rats received restraint stress during the last week of pregnancy. Hippocampal glucocorticoid receptor expression levels in the offspring were detected on postnatal 60 (P60).Cognition function was also detected. It shows significantly lower hippocampal GR expression was observed in female prenatally stressed offspring compared with their controls at P60. Corresponding to the expression of GR, female prenatally stressed offspring exhibited poorer spatial learning and memory abilities in the Barnes maze than control, This suggests that cognitive impairment in prenatally stressed rat offspring attribute lower hippocampal GR expression.


La evidencia acumulada de estudios preclínicos y clínicos indica que la exposición prenatal al estrés, o el exceso de glucocorticoides puede afectar el desarrollo cerebral de las crías. El receptor de glucocorticoides (RG) es un objetivo importante de los glucocorticoides. Por lo tanto, el objetivo del presente estudio fue investigar la expresión de RG en crías adultas estresadas durante el período prenatal y la relación entre la expresión de RG y el comportamiento de las crías. Las ratas preñadas recibieron niveles de estrés restringido, durante la última semana de embarazo. Se determinaron niveles de expresión del receptor de glucocorticoides del hipocampo y niveles de función cognitiva en las crías. En comparación con el grupo control se observó una expresión de RG en el hipocampo, significativamente menor en las crías estresadas prenatalmente, en comparación con los controles en P60. En referencia a la expresión de RG, las crías estresadas prenatalmente exhibieron habilidades de memoria y aprendizaje espacial menores, en el laberinto de Barnes que el grupo control. Esto sugiere que el deterioro cognitivo en crías de ratas estresadas prenatalmente muestran una menor expresión de RG en el hipocampo.


Assuntos
Animais , Feminino , Gravidez , Ratos , Efeitos Tardios da Exposição Pré-Natal , Receptores de Glucocorticoides/metabolismo , Disfunção Cognitiva , Hipocampo/metabolismo , Estresse Fisiológico , Imuno-Histoquímica , Western Blotting , Ratos Sprague-Dawley
2.
PLoS One ; 15(1): e0227520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923266

RESUMO

Glucocorticoid (GR) and mineralocorticoid receptors (MR) are believed to classically bind DNA as homodimers or MR-GR heterodimers to influence gene regulation in response to pulsatile basal or stress-evoked glucocorticoid secretion. Pulsed corticosterone presentation reveals MR and GR co-occupy DNA only at the peaks of glucocorticoid oscillations, allowing interaction. GR DNA occupancy was pulsatile, while MR DNA occupancy was prolonged through the inter-pulse interval. In mouse mammary 3617 cells MR-GR interacted in the nucleus and at a chromatin-associated DNA binding site. Interactions occurred irrespective of ligand type and receptors formed complexes of higher order than heterodimers. We also detected MR-GR interactions ex-vivo in rat hippocampus. An expanded range of MR-GR interactions predicts structural allostery allowing a variety of transcriptional outcomes and is applicable to the multiple tissue types that co-express both receptors in the same cells whether activated by the same or different hormones.


Assuntos
Núcleo Celular/metabolismo , DNA/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Regulação Alostérica , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Cromatina/metabolismo , Corticosterona/farmacologia , DNA/química , Dimerização , Hipocampo/metabolismo , Masculino , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Estrutura Quaternária de Proteína , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/química , Receptores de Mineralocorticoides/genética , Alinhamento de Sequência , Ritmo Ultradiano
3.
PLoS One ; 15(1): e0227456, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31935235

RESUMO

Endometriosis is a chronic inflammatory disorder in which endometrial tissue is found outside the uterine cavity. Previous reports suggest that there is a dysregulation of the hypothalamic pituitary adrenal axis during the progression of endometriosis. Our previous report showed that a short-term treatment with antalarmin, a corticotrophin releasing hormone receptor type 1 (CRHR1) antagonist decreases the number and size of endometriotic vesicles in the auto-transplantation rat model of endometriosis. Our current goal was to examine the mRNA expression of intra-adrenal receptors to better understand the mechanisms of the hypothalamic pituitary adrenal (HPA) axis involvement in endometriosis. We used two groups of female rats. The first received sham surgery or endometriosis surgery before collecting the adrenals after 7 days of the disease progression. The second group of animals received endometriosis surgery and a treatment of either vehicle or antalarmin (20 mg/kg, i.p.) during the first 7 days after endometriosis induction and then the disease was allowed to progress until day 60. Rats with sham surgery served as controls. Results showed that the mRNA expression of the mineralocorticoid (MRC2) receptor was lower in the rats after 7 days of endometriosis surgery and in rats with endometriosis that received antalarmin. In addition, the CRHR1 was significantly elevated in animals that received antalarmin and this was counteracted by a non-significant elevation in CRHR2 mRNA. The glucocorticoid receptor mRNA within the adrenals was not affected by endometriosis or antalarmin treatment. This report is one of the first to explore intra-adrenal mRNA for receptors involved in the HPA axis signaling as well as in the sympatho-adrenal signaling, calling for additional research towards understanding the role of the adrenal glands in chronic inflammatory diseases such as endometriosis.


Assuntos
Glândulas Suprarrenais/metabolismo , Endometriose/tratamento farmacológico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Animais , Modelos Animais de Doenças , Endometriose/patologia , Endometriose/cirurgia , Feminino , Sistema Hipófise-Suprarrenal/metabolismo , RNA Mensageiro/metabolismo , Ratos , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Receptores de Hormônio Liberador da Corticotropina/genética , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética , Regulação para Cima
4.
Biochim Biophys Acta Gene Regul Mech ; 1863(1): 194475, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31870784

RESUMO

Targeting the apoptosis machinery is a promising therapeutic approach in myeloid malignancies. BCL2L1 is a well-known glucocorticoid-responsive gene and a key apoptosis regulator that, when over-expressed, can contribute to tumor development, progression and therapeutic resistance. Moreover, synthetic glucocorticoids, like dexamethasone, are frequently used in the treatment of hematopoietic diseases due to its pro-apoptotic properties. We report here that the trithorax protein ASH2L, considered one of the core subunits of H3K4-specific MLL/SET methyltransferase complexes, contributes to anti-apoptotic BCL-XL over-expression and cell survival in patient-derived myeloid leukemia cells. We find that the unliganded glucocorticoid receptor (uGR) and ASH2L interact in a common protein complex through a chromatin looping determined by uGR and ASH2L binding to BCL2L1 specific +58 HRE and promoter region, respectively. Upon addition of dexamethasone, GR and ASH2L recruitment is reduced, BCL-XL expression diminishes and apoptosis is induced consequently. Overall, our findings indicate that uGR and ASH2L may act as key regulatory players of BCL- XL upregulation in AML cells.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Glucocorticoides/farmacologia , Leucemia Mieloide Aguda/genética , Proteínas Nucleares/metabolismo , Receptores de Glucocorticoides/metabolismo , Fatores de Transcrição/metabolismo , Proteína bcl-X/genética , Apoptose , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/metabolismo , Regiões Promotoras Genéticas , Elementos de Resposta , Células U937 , Proteína bcl-X/metabolismo
5.
J Ethnopharmacol ; 246: 112165, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31445133

RESUMO

Blood-brain barrier (BBB) is a barrier which maintains the material exchange balance of brain microenvironment and could be destroyed by chronic stress (CS). Glucocorticoids (GCs) can mimic the chronic stress induced damage to BBB. GCs induced BBB trauma models in vitro and in vivo to explore the effects of the traditional medicine Xiao-Yao-San (XYS). In this research, we found CS could injure the BBB to change the biochemical index, which could be reversed by XYS in vitro. The abilities of cell proliferation, invasion, and the expression of tight junction related genes (Occludin, Claudin, JAM-1 and ZO-1) were suppressed by CS and the trauma could be reversed by XYS partly. It was showed that GRs interacted with Occludin directly and inhibited Occluding expression. In rats BBB trauma model, the GC content was deceased and BBB permeability was repaired by XYS. The expression of Occludin, Claudin, JAM-1 and ZO-1 were increased in the treatment of XYS. In our research, it shown that XYS affect the content of the GC and GR which interacted with Occludin directly for the first time. In addition, we also found that XYS could reduce BBB injury induced by CS via GR in BBB model in vitro. Therefore, it proves that XYS is a potential BBB repair medicine and may help to elucidate mechanism of brain pathology.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Fisiológico , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Masculino , Ratos Sprague-Dawley , Ratos Wistar , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo , Regulação para Cima
6.
Medicina (B Aires) ; 79(Spec 6/1): 540-545, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31864223

RESUMO

Seventy per cent of breast cancers are luminal carcinomas that express estrogen receptor alpha (ER). For several decades, its expression has been used as a therapeutic target in patients with breast cancer. These therapies are aimed at blocking ER or inhibiting ligand synthesis. The expression of progesterone receptors (PR) is evaluated as a prognostic factor together with ER. It has been shown that there are two predominant PR isoforms with different molecular weight, isoform A and isoform B, which are not distinguished by immunohistochemical techniques. The available evidence indicates that the PR isoform ratio may have both a prognostic and predictive value of the response to antiprogestin treatment. In luminal mammary carcinomas, androgen receptors (AR) are expressed in a high percentage and the AR/ER or AR/PR ratio could be a prognostic factor. In ER negative (-) tumors, AR expression is an indicator of poor prognosis and it is proposed that they may be susceptible to antiandrogen treatment. Finally, the expression of glucocorticoid receptors (GR) would be an indicator of good or bad prognosis in luminal or ER- tumors, respectively. In ER- tumors, metastases express higher levels of nuclear GR than primary tumors and therapies that block GR could improve the efficacy of chemotherapy. Given the crosstalk of pathways triggered by different hormone receptors, it is possible that in the future, a therapeutic scheme can be administered that contemplates the expression of ER, PR isoforms, AR and GR.


Assuntos
Neoplasias da Mama/metabolismo , Receptores Androgênicos/metabolismo , Receptores Estrogênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Biomarcadores/metabolismo , Neoplasias da Mama/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Prognóstico , Receptores Androgênicos/genética , Receptores Estrogênicos/genética , Receptores de Glucocorticoides/genética , Receptores de Progesterona/genética
7.
PLoS One ; 14(12): e0226753, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31869387

RESUMO

Stress is a major risk factor for depression and anxiety. One of the effects of stress is the (over-) activation of the hypothalamic-pituitary-adrenal (HPA) axis and the release of stress hormones such as glucocorticoids (GCs). Chronically increased stress hormone levels have been shown to have detrimental effects on neuronal networks by inhibiting neurotrophic processes particularly in the hippocampus proper. Centrally, GCs modulate metabolic as well as behavioural processes by activating two classes of corticoid receptors, high-affinity mineralocorticoid receptors (MR) and low-affinity glucocorticoid receptors (GR). Upon activation, GR can modulate gene transcription either as a monomeric protein, or as a dimer interacting directly with DNA. GR can also modulate cellular processes via non-genomic mechanisms, for example via a GPCR-protein interaction. We evaluated the behavioral phenotype in mice with a targeted mutation in the GR in a FVB/NJ background. In GRdim/dim mice, GR proteins form poor homodimers, while the GR monomer remains intact. We evaluated the effect of poor GR dimerization on hippocampus-dependent cognition as well as on exploration and emotional behavior under baseline and chronically increased stress hormone levels. We found that GRdim/dim mice did not behave differently from GRwt/wt littermates under baseline conditions. However, after chronic elevation of stress hormone levels, GRdim/dim mice displayed a significant impairment in hippocampus-dependent memory compared to GRwt/wt mice, which correlated with differential expression of hippocampal Bdnf/TrkB and Fkbp5.


Assuntos
Disfunção Cognitiva/metabolismo , Receptores de Glucocorticoides/metabolismo , Animais , Comportamento Animal , Cognição , Disfunção Cognitiva/genética , Feminino , Glucocorticoides/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Mutação , Multimerização Proteica , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/genética
8.
Anticancer Res ; 39(11): 5879-5890, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31704812

RESUMO

BACKGROUND/AIM: The aim of the study was to investigate the prognostic role of androgen receptor (AR), mineralocorticoid receptor (MR) and glucocorticoid receptor ß (GRß) expression in HER-2 negative breast cancer patients. MATERIALS AND METHODS: The study population (n=152) was enriched with triple-negative breast cancers (TNBC) (n=96; 63.2%). The median follow-up time was 100 months. AR, MR and GRß immunocytochemical staining was compared with that of epithelial-mesenchymal transition (EMT) markers (vimentin, SIP1, ZEB1). RESULTS: High expression of cytoplasmic MR was associated with dismal local relapse-free survival (RR=13.923; 95%CI=1.071-181.045; p=0.044) in tumours with non-TNBC phenotype. AR and GRß were more frequently expressed in ER+/PR+/HER2- tumours, while cytoplasmic MR was more often expressed in TNBC tumours (for all, p<0.0005). GRß and AR were associated with decreased vimentin expression (p<0.005), indicating their association with attenuated EMT. CONCLUSION: Cytoplasmic MR expression is a strong predictor of local recurrence in non-metastatic breast cancer patients with non-TNBC tumour phenotype.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/classificação , Neoplasias da Mama/mortalidade , Citoplasma/metabolismo , Recidiva Local de Neoplasia/mortalidade , Receptores de Mineralocorticoides/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Metástase Neoplásica , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Prognóstico , Receptor ErbB-2/metabolismo , Receptores Androgênicos/metabolismo , Receptores Estrogênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Taxa de Sobrevida
9.
Mol Cell ; 76(4): 531-545.e5, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31706703

RESUMO

The glucocorticoid receptor (GR) is a potent metabolic regulator and a major drug target. While GR is known to play integral roles in circadian biology, its rhythmic genomic actions have never been characterized. Here we mapped GR's chromatin occupancy in mouse livers throughout the day and night cycle. We show how GR partitions metabolic processes by time-dependent target gene regulation and controls circulating glucose and triglycerides differentially during feeding and fasting. Highlighting the dominant role GR plays in synchronizing circadian amplitudes, we find that the majority of oscillating genes are bound by and depend on GR. This rhythmic pattern is altered by high-fat diet in a ligand-independent manner. We find that the remodeling of oscillatory gene expression and postprandial GR binding results from a concomitant increase of STAT5 co-occupancy in obese mice. Altogether, our findings highlight GR's fundamental role in the rhythmic orchestration of hepatic metabolism.


Assuntos
Cromatina/metabolismo , Relógios Circadianos , Ritmo Circadiano , Dieta Hiperlipídica , Gorduras na Dieta/metabolismo , Metabolismo Energético , Fígado/metabolismo , Obesidade/metabolismo , Receptores de Glucocorticoides/metabolismo , Animais , Glicemia/metabolismo , Relógios Circadianos/genética , Ritmo Circadiano/genética , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/sangue , Modelos Animais de Doenças , Metabolismo Energético/genética , Jejum/metabolismo , Regulação da Expressão Gênica , Glucocorticoides/metabolismo , Gluconeogênese , Ligantes , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/sangue , Obesidade/genética , PPAR alfa/genética , PPAR alfa/metabolismo , Período Pós-Prandial , Receptores de Glucocorticoides/deficiência , Receptores de Glucocorticoides/genética , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Via Secretória , Transdução de Sinais , Fatores de Tempo , Transcrição Genética , Triglicerídeos/sangue
10.
Int J Mol Sci ; 20(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510090

RESUMO

The negative association between psychological stress and male fertility has been known for many years. This study was aimed at (i) identifying spermatogenesis impairment induced by psychological stress in rats and (ii) exploring the role of glucocorticoid receptor (GR) signaling in these adverse effects (if they exist). Male Sprague Dawley rats were exposed to a six-week period of unpredictable chronic mild stress (uCMS) along with cotreatment of GR antagonist RU486 (1 mg/kg/day). Testicular damage was assessed by testicular pathological evaluation, epididymal sperm concentration, serum testosterone levels, testicular apoptotic cell measurements, and cell cycle progression analyses. Rats in the uCMS group had decreased levels of serum testosterone and decreased epididymal sperm concentration. The uCMS-treated rats also had decreased numbers of spermatids and increased levels of apoptotic seminiferous tubules; additionally, cell cycle progression of spermatogonia was arrested at the G0/G1 phase. Furthermore, uCMS exposure caused an increase in serum corticosterone level and activated GR signaling in the testes including upregulated GR expression. RU486 treatment suppressed GR signaling and alleviated the damaging effects of stress, resulting in an increased epididymal sperm concentration. Overall, this work demonstrated for the first time that the activation of GR signaling mediates stress-induced spermatogenesis impairment and that this outcome is related to cell apoptosis and cell cycle arrest in germ cells.


Assuntos
Epididimo/metabolismo , Receptores de Glucocorticoides/metabolismo , Espermatogênese/fisiologia , Espermatozoides/metabolismo , Estresse Psicológico/fisiopatologia , Testículo/metabolismo , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Epididimo/citologia , Epididimo/efeitos dos fármacos , Masculino , Mifepristona/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/antagonistas & inibidores , Túbulos Seminíferos/citologia , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/metabolismo , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/citologia , Testículo/efeitos dos fármacos , Testosterona/sangue
11.
Mol Carcinog ; 58(12): 2297-2305, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31535408

RESUMO

Glucocorticoids, including dexamethasone (DEX) and prednisone (PRED), have been prescribed in patients with neoplastic disease as cytotoxic agents or comedications. Nonetheless, it remains uncertain whether they have an impact on the development of bladder cancer. We, therefore, assessed the functional role of the glucocorticoid-mediated glucocorticoid receptor (GR) signaling in urothelial tumorigenesis. Tumor formation was significantly delayed in xenograft-bearing mice with implantation of control bladder cancer UMUC3 cells or nonneoplastic urothelial SVHUC cells undergoing malignant transformation induced by a chemical carcinogen 3-methylcholanthrene (MCA), compared with respective GR knockdown xenografts. Using the in vitro system with MCA-SVHUC cells, we screened 11 GR ligands, including DEX, and found significant inhibitory effects of PRED on their neoplastic transformation. The effects of PRED were restored by a GR antagonist RU486 in GR-positive MCA-SVHUC cells, while PRED failed to inhibit the neoplastic transformation of GR knockdown cells. Significant decreases in the expression levels of oncogenes (c-Fos/c-Jun) and significant increases in those of a tumor suppressor UGT1A were seen in MCA-SVHUC-control cells (vs GR-short hairpin RNA) or PRED-treated MCA-SVHUC-control cells (vs mock). In addition, N-butyl-N-(4-hydroxybutyl) nitrosamine induced bladder cancer in all of eight mock-treated mice vs seven (87.5%) of DEX-treated (P = .302) or four (50%) of PRED-treated (P = .021) animals. Finally, DEX was found to considerably induce both transactivation (activation of glucocorticoid-response element mediated transcription and expression of its targets) and transrepression (suppression of nuclear factor-kappa B transactivation and expression of its regulated genes) of GR in SVHUC cells, while PRED more selectively induced GR transrepression. These findings suggest that PRED could prevent urothelial tumorigenesis presumably via inducing GR transrepression.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Glucocorticoides/farmacologia , Receptores de Glucocorticoides/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Urotélio/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Linhagem Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Interferência de RNA , Receptores de Glucocorticoides/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/citologia , Urotélio/metabolismo
12.
Biomed Pharmacother ; 118: 109380, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545224

RESUMO

BACKGROUND: Corticosteroid is one of the main treatments for interstitial lung disease (ILD). Cryptogenic-organizing pneumonia (COP) is sensitive to corticosteroid therapy, whereas idiopathic pulmonary fibrosis (IPF) is not. Glucocorticoid receptor-α (GR-α) and histone deacetylase 2 (HDAC2) play critical roles in the sensitivity to corticosteroid therapy; however, it is unclear whether HDAC2 and/or GR-α are expressed in the lung tissues of patients with COP and/or IPF. Possible aberrant expressions of HDAC2 and GR-α in IPF and COP were investigated in the current study. METHODS: Lung tissue samples were obtained from patients with COP (n = 9), IPF (n = 8), pulmonary abscesses (n = 7), or pulmonary inflammatory pseudotumors (n = 6) before corticosteroid treatment, as well as from control subjects (n = 10). The expression of GR-α, HDAC2, PI3K-δ, and NF-κBp65 in the samples was assessed by immunohistochemistry. RESULTS: GR-α expression was the same in lung tissues from COP patients and control subjects, but was significantly lower in lung tissue from IPF. In addition, HDAC2 was significantly higher in lung tissues of COP patients compared to both IPF and control subjects. Furthermore, the transcription factor NF-κBp65 was significantly lower in lung tissues from both COP and control compared to IPF subjects, whereas there was no difference in NF-κBp65 when comparing tissues from COP patients to controls. HDAC2 and GR-α were negatively correlated with NF-κBp65 in COP lung tissue. CONCLUSION: HDAC2 and GR-α expression in lung tissues are potential biomarkers for predicting corticosteroid sensitivity when initially treating COP and IPF, as well as other forms of ILD.


Assuntos
Histona Desacetilase 2/metabolismo , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/metabolismo , Receptores de Glucocorticoides/metabolismo , Esteroides/uso terapêutico , Pneumonia em Organização Criptogênica/complicações , Pneumonia em Organização Criptogênica/patologia , Pneumonia em Organização Criptogênica/fisiopatologia , Feminino , Humanos , Pulmão/patologia , Pulmão/fisiopatologia , Doenças Pulmonares Intersticiais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição RelA/metabolismo
13.
J Agric Food Chem ; 67(39): 10871-10879, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31517482

RESUMO

This study evaluated the effect of triterpenoids from edible mushroom Poria cocos on intestinal epithelium integrity and revealed the transcriptional regulatory pathways that underpin restorative mechanisms in the gut. Based on computational docking studies, transcriptional activation experiments and glucocorticoid receptor (GR) protein immunofluorescence localization assays in cultured cells, 16α-hydroxytrametenolic acid (HTA) was discovered as a novel GR agonist in this study. HTA ameliorates TNF-α-induced Caco-2 monolayer intestinal epithelial barrier damage and suppressed activation of phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt), which attenuated downstream IκB and nuclear factor kappa-B (NF-κB) phosphorylation through GR activation. Moreover, HTA prevented NF-κB translocation into the nucleus and binding to its cis-element and suppressed lipopolysaccharide-induced downstream NO production and pro-inflammatory cytokines at both protein and mRNA expression levels. In conclusion, HTA from P. cocos improves intestinal barrier function through a GR-mediated PI3K/Akt/NF-κB signaling pathway and may be potentially exploited as a supportive dietary therapeutic strategy for restoring gut health.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Glucocorticoides/metabolismo , Triterpenos/farmacologia , Wolfiporia/química , Células CACO-2 , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Mucosa Intestinal/metabolismo , Simulação de Acoplamento Molecular , NF-kappa B/genética , Fosfatidilinositol 3-Quinase/genética , Fosforilação , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Glucocorticoides/genética , Transdução de Sinais/efeitos dos fármacos , Triterpenos/química , Verduras/química
14.
Mol Pharmacol ; 96(4): 408-417, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31391291

RESUMO

Both synthetic and endogenous glucocorticoids are important pharmaceutic drugs known to bind to the ligand-binding domain (LBD) of glucocorticoid receptor (GR), a member of the nuclear receptor (NR) superfamily. Ligand binding induces conformational changes within GR, resulting in subsequent DNA binding and differential coregulator recruitment, ultimately activating or repressing target gene expression. One of the most crucial coregulators is peroxisome proliferator-activated γ coactivator 1-α (PGC1α), which acts to regulate energy metabolism by directly interacting with GR to modulate gene expression. However, the mechanisms through which PGC1α senses GR conformation to drive transcription are not completely known. Here, an ancestral variant of the GR (AncGR2) LBD was used as a tool to produce stable protein for biochemical and structural studies. PGC1α is found to interact more tightly and form a more stable complex with AncGR2 LBD than nuclear receptor coactivator 2. We report the first high-resolution X-ray crystal structures of AncGR2 LBD in complex with PGC1α and dexamethasone (DEX) or hydrocortisone (HCY). Structural analyses reveal how distinct steroid drugs bind to GR with different affinities by unique hydrogen bonds and hydrophobic interactions. Important charge clamps are formed between the activation function 2 and PGC1α to mediate their specific interactions. These interactions lead to a high level of protection from hydrogen-deuterium exchange at the coregulator interaction site and strong intramolecular allosteric communication to ligand binding site. This is the first structure detailing the GR-PGC1α interaction providing a foundation for future design of specific therapeutic agents targeting these critical metabolic regulators. SIGNIFICANCE STATEMENT: High-resolution structures of AncGR2 LBD bound to DEX and HCY in complex with PGC1α reveal the molecular mechanism of PGC1α binding to AncGR2 LBD as well as the distinct affinities between DEX and HCY binding. Identifying the structural mechanisms that drive drug affinity is of pharmacologic interest to the glucocorticoid receptor field as an avenue to guide future drug design targeting GR-PGC1α signaling, which plays a crucial role in controlling hepatic glucose output.


Assuntos
Glucocorticoides/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Células HeLa , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Modelos Moleculares , Simulação de Dinâmica Molecular , Coativador 2 de Receptor Nuclear/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína
15.
Biol Pharm Bull ; 42(10): 1746-1752, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31391381

RESUMO

Genetic variations in glucocorticoid-induced transcript 1 (GLCCI1) have been associated with the response to corticosteroid treatment. However, the associations of GLCCI1 polymorphisms or gene expression with the prognosis of asthma and pathophysiological factors related to steroid insensitivity remain unclear. We sought to investigate the associations of GLCCI1, nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and histone deacetylase 2 (HDAC2) mRNA expression levels and the GLCCI1 rs37973 polymorphism with asthma severity and future exacerbation in patients with asthma. Subjects included 25 patients with severe asthma and 127 patients with nonsevere asthma. mRNA expression levels in peripheral blood mononuclear cells were measured and evaluated as predictors of severe asthma using receiver operating characteristic (ROC) analysis. The hazard ratios of the mRNA expression levels for time to first exacerbation in the 1-year follow-up period were calculated. GLCCI1, Nrf2, and HDAC2 mRNA expression levels were significantly lower in patients with severe asthma than in patients with nonsevere asthma and could predict severe asthma with an area under the ROC curve of 0.68, 0.71, and 0.65, respectively. In contrast, no relationship was found between the GLCCI1 rs37973 polymorphism and severe asthma. The hazard ratios for asthma exacerbation in patients with low GLCCI1, Nrf2, and HDAC2 mRNA expression levels were 3.24 (95% confidence interval, 1.42-7.40), 3.13 (1.37-7.16), and 2.98 (1.22-7.25), respectively. Patients with severe asthma could be distinguished by lower GLCCI1, Nrf2, and HDAC2 mRNA levels in peripheral blood cells, and all of these gene signatures could predict future asthma exacerbations.


Assuntos
Corticosteroides/uso terapêutico , Asma/genética , Genótipo , Polimorfismo de Nucleotídeo Único , Receptores de Glucocorticoides/metabolismo , Índice de Gravidade de Doença , Administração por Inalação , Idoso , Área Sob a Curva , Asma/tratamento farmacológico , Asma/metabolismo , Feminino , Expressão Gênica , Glucocorticoides/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , RNA Mensageiro/metabolismo , Curva ROC , Receptores de Glucocorticoides/genética
16.
Eur J Appl Physiol ; 119(10): 2237-2253, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31420735

RESUMO

PURPOSE: Stressful training with insufficient recovery can impair muscle performance. Expression of mitogen-activated protein kinases (MAPK) has been reported at rest following overreaching and overtraining. The acute myocellular exercise response to stressful training with insufficient recovery has not been investigated. We investigated MAPK, androgen, and glucocorticoid receptor phosphorylation following a period of stressful training. METHODS: Sixteen resistance-trained men were matched on barbell squat 1 repetition maximum strength and randomized into a group that performed normal training or stressful training with insufficient recovery. The control group (CON) performed three speed-squat training sessions on non-consecutive days, while the stressful training group (NFOR) performed 15 training sessions over 7.5 days. Resting and post-exercise skeletal muscle biopsies were obtained prior to (T1) and after the training period (T2). Samples were analyzed for total and phosphorylated androgen receptor (AR), glucocorticoid receptor (GR), and MAPKs (ERK, JNK, and p38). RESULTS: Total AR were down-regulated post-exercise at T2 in NFOR only. Phospho-AR at ser515 increased in both groups post-exercise at T1; however, ser515 only increased at T2 in NFOR. Phosphorylated ERK, JNK, and p38 increased post-exercise in CON and NFOR at T1 and T2. Post-exercise phospho-p38 was blunted in NFOR at T2 compared to T1. After the training intervention, resting phospho-p38 was higher in NFOR compared to T1. At T2, post-exercise phospho-GR at ser226 was lower compared to T1, and resting levels increased in NFOR. CONCLUSION: Steroid receptors are phosphorylated after acute resistance exercise, and in addition to MAPKs, are differentially regulated after stressful training with insufficient recovery.


Assuntos
Sistema de Sinalização das MAP Quinases , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Treinamento de Resistência/métodos , Estresse Fisiológico , Regulação para Baixo , Humanos , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Masculino , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Fosforilação , Receptores Androgênicos/genética , Receptores de Glucocorticoides/genética , Recuperação de Função Fisiológica , Treinamento de Resistência/efeitos adversos , Adulto Jovem , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Mol Cell ; 75(6): 1161-1177.e11, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31421980

RESUMO

Genes are transcribed in a discontinuous pattern referred to as RNA bursting, but the mechanisms regulating this process are unclear. Although many physiological signals, including glucocorticoid hormones, are pulsatile, the effects of transient stimulation on bursting are unknown. Here we characterize RNA synthesis from single-copy glucocorticoid receptor (GR)-regulated transcription sites (TSs) under pulsed (ultradian) and constant hormone stimulation. In contrast to constant stimulation, pulsed stimulation induces restricted bursting centered around the hormonal pulse. Moreover, we demonstrate that transcription factor (TF) nuclear mobility determines burst duration, whereas its bound fraction determines burst frequency. Using 3D tracking of TSs, we directly correlate TF binding and RNA synthesis at a specific promoter. Finally, we uncover a striking co-bursting pattern between TSs located at proximal and distal positions in the nucleus. Together, our data reveal a dynamic interplay between TF mobility and RNA bursting that is responsive to stimuli strength, type, modality, and duration.


Assuntos
Glucocorticoides/farmacologia , Regiões Promotoras Genéticas , RNA/biossíntese , Receptores de Glucocorticoides/metabolismo , Sítio de Iniciação de Transcrição , Transcrição Genética/efeitos dos fármacos , Animais , Camundongos , RNA/genética
18.
Immunobiology ; 224(5): 614-624, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427114

RESUMO

Thymus-derived T regulatory (tTregs) cells play a crucial role in the maintenance of tolerance and immune homeostasis. Mechanisms and factors regulating tTreg development and function are widely investigated, but to a large degree still remain unclear. Our previous findings demonstrated that, in physiological conditions, the development and suppressive function of tTregs demonstrated day/night rhythmicity, which correlated with the concentration of plasma corticosterone and the expression of glucocorticoid receptors. In this study we ask whether synthetic glucocorticoids commonly used to inhibit excessive activity of the immune system, can modulate the development and suppressive function of tTregs in vivo depending on the time of administration. Young C57BL/6 male and female mice were injected intraperitoneally with a single dose of dexamethasone at two time points of the day: 7.00-8.00 a.m. and 7.00-8.00 p.m. The experimental can be used to indicate on the potentially expected positive or adverse side effects and can constitute also a good model for the assessment of the effects of long-term therapy. The results of our studies demonstrated the increase of the percentage of tTregs at both time points in male mice, but only in the evening in females. The suppressive activity of tTregs increased independently on the day time of in female mice, but in the morning only in males. We concluded that in the condition of dexamethasone supplementation, the elevated suppressive potential of tTregs is balanced by the induction apoptosis in order to prevent excessive suppression.


Assuntos
Dexametasona/farmacologia , Fotoperíodo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/fisiologia , Timócitos/efeitos dos fármacos , Timócitos/fisiologia , Animais , Apoptose , Biomarcadores , Diferenciação Celular , Dexametasona/administração & dosagem , Feminino , Glucocorticoides/sangue , Glucocorticoides/metabolismo , Imunofenotipagem , Masculino , Camundongos , Fenótipo , Receptores de Glucocorticoides/metabolismo , Linfócitos T Reguladores/citologia , Timócitos/citologia
19.
Int Immunopharmacol ; 75: 105806, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401378

RESUMO

Microglial inflammation plays crucial role in the pathogenesis of CNS infections including brain abscesses. Staphylococcus aureus (S. aureus) is considered as one of the major causative agents of brain abscesses. Due to the emergence of multidrug resistant bacteria the available treatment options including conventional antibiotics and steroid therapy become ineffective in terms of inflammation regulation which warrants further investigation to resolve this health issue. Microglial TLR-2 plays important roles in the bacterial recognition as well as induction of inflammation whereas glucocorticoid receptor (GR) triggers anti-inflammatory pathways in presence of glucocorticoids (GCs). The main objective of this study was to figure out the interdependency between TLR-2 and GR in presence of exogenous dexamethasone during microglial inflammation as an alternative therapeutic approach. Experiments were done either in TLR-2 neutralized condition or GR blocked condition in presence of dexamethasone. Free radicals production, arginase, superoxide dismutase (SOD), catalase enzyme activities and corticosterone concentration were measured along with Western blot analysis of TLR-2, GR and other inflammatory molecules. The results suggested that dexamethasone pre-treatment in TLR-2 neutralized condition efficiently reduces the inflammatory consequences of S. aureus induced microglial inflammation through up regulating GR expression. During TLR-2 blocking dexamethasone exerted its potent anti-inflammatory activities via suppressing reactive oxygen species (ROS), NO production and up regulating arginase, SOD and catalase activities at the time point of 90 min. Further in-vivo experiments are needed to conclude that dexamethasone could resolve brain inflammation possibly through microglial phenotypic switching from pro-inflammatory M1 to anti-inflammatory M2.


Assuntos
Anti-Inflamatórios/farmacologia , Dexametasona/farmacologia , Microglia/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Infecções Estafilocócicas/metabolismo , Staphylococcus aureus , Receptor 2 Toll-Like/metabolismo , Animais , Masculino , Camundongos , Microglia/metabolismo
20.
Chin Med J (Engl) ; 132(16): 1942-1950, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31365430

RESUMO

BACKGROUND: Henoch-Schonlein purpura nephritis (HSPN) is a very common secondary kidney disease of childhood. Its pathogenesis and the treatment mechanism of glucocorticoid have not been fully elucidated. The aim of this study was to determine the relationship between p300 and the pathogenesis, glucocorticoid therapy in mice with HSPN, respectively. METHODS: Forty-eight C57BL/6N male mice, weighing 18 to 20 g, were selected (3-4 weeks old, n = 8 per group). The mice in the normal control group (Group I) were given normal solvent and the HSPN model group (Group II) were given sensitizing drugs. The mice in Group III were injected intraperitoneally with dexamethasone after being given sensitizing drugs. Meanwhile, mice in Groups IV, V and VI with conditional knockout of p300 were also given normal solvent, sensitizing drugs and dexamethasone.The levels of serum IgA, creatinine, and circulating immune complex (CIC) concentrations, 24 h urinary protein and urinary erythrocyte in C57 wild mice, and p300 conditional knockout mice in each group were measured. The expression of p300 in renal tissues and the expression of glucocorticoid receptor (GR) α and ß, transforming growth factor (TGF)-ß1, and activator protein (AP)-1 after dexamethasone treatment were determined by real-time polymerase chain reaction and Western blotting. RESULTS: Compared with the normal solvent control group (Group I), the expression of p300 mRNA in the model group (Group II) was significantly up-regulated. Western blotting further confirmed the result. Urinary erythrocyte count, 24 h urinary protein quantification, serum IgA, CIC, and renal pathologic score in Group V were distinctly decreased compared with non-knockout mice in Group II (9.7 ±â€Š3.8 per high-power field [/HP] vs. 18.7 ±â€Š6.2/HP, t = 1.828, P = 0.043; 0.18 ±â€Š0.06 g/24 h vs. 0.36 ±â€Š0.08 g/24 h, t = 1.837, P = 0.042; 18.78 ±â€Š0.85 mg/mL vs. 38.46 ±â€Š0.46 mg/mL, t = 1.925, P = 0.038; 0.80 ±â€Š0.27 µg/mL vs. 1.64 ±â€Š0.47 µg/mL, t = 1.892, P = 0.041; 7.0 ±â€Š0.5 vs. 18.0 ±â€Š0.5, t = 1.908, P = 0.039). Compared with non-knockout mice (Group III), the level of urinary erythrocyte count and serum IgA in knockout mice (Group VI) increased significantly after treatment with dexamethasone (3.7 ±â€Š0.6/HP vs. 9.2 ±â€Š3.5/HP, t = 2.186, P = 0.024; 12.38 ±â€Š0.26 mg/mL vs. 27.85 ±â€Š0.65 mg/mL, t = 1.852, P = 0.041). The expression level of GRα was considerably increased in the knockout group after dexamethasone treatment compared with non-knockout mice in mRNA and protein level (t = 2.085, P = 0.026; t = 1.928, P = 0.035), but there was no statistically significant difference in the expression level of GRß between condition knockout and non-knockout mice (t = 0.059, P = 0.087; t = 0.038, P = 1.12). Furthermore, the expression levels of glucocorticoid resistance genes (AP-1 and TGF-ß1) were notably increased after p300 knockout compared with non-knockout mice in mRNA and protein level (TGF-ß1: t = 1.945, P = 0.034; t = 1.902, P = 0.039; AP-1: t = 1.914, P = 0.038; t = 1.802, P = 0.041). CONCLUSIONS: p300 plays a crucial role in the pathogenesis of HSPN. p300 can down-regulate the expression of resistance genes (AP-1 and TGF-ß1) by binding with GRα to prevent further renal injury and glucocorticoid resistance. Therefore, p300 is a promising new target in glucocorticoid therapy in HSPN.


Assuntos
Dexametasona/uso terapêutico , Glucocorticoides/uso terapêutico , Nefrite/tratamento farmacológico , Nefrite/metabolismo , Púrpura de Schoenlein-Henoch/tratamento farmacológico , Púrpura de Schoenlein-Henoch/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Creatinina/sangue , Humanos , Imunoglobulina A/sangue , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nefrite/sangue , Nefrite/genética , Púrpura de Schoenlein-Henoch/sangue , Púrpura de Schoenlein-Henoch/genética , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Fatores de Crescimento Transformadores/genética , Fatores de Crescimento Transformadores/metabolismo , Fatores de Transcrição de p300-CBP/genética
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