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1.
Nat Commun ; 12(1): 1987, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33790284

RESUMO

A widely regarded model for glucocorticoid receptor (GR) action postulates that dimeric binding to DNA regulates unfavorable metabolic pathways while monomeric receptor binding promotes repressive gene responses related to its anti-inflammatory effects. This model has been built upon the characterization of the GRdim mutant, reported to be incapable of DNA binding and dimerization. Although quantitative live-cell imaging data shows GRdim as mostly dimeric, genomic studies based on recovery of enriched half-site response elements suggest monomeric engagement on DNA. Here, we perform genome-wide studies on GRdim and a constitutively monomeric mutant. Our results show that impairing dimerization affects binding even to open chromatin. We also find that GRdim does not exclusively bind half-response elements. Our results do not support a physiological role for monomeric GR and are consistent with a common mode of receptor binding via higher order structures that drives both the activating and repressive actions of glucocorticoids.


Assuntos
DNA/metabolismo , Estudo de Associação Genômica Ampla/métodos , Multimerização Proteica , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , DNA/genética , Regulação da Expressão Gênica , Glucocorticoides/metabolismo , Humanos , Camundongos , Mutação , Ligação Proteica , Receptores de Glucocorticoides/genética , Elementos de Resposta/genética , Transdução de Sinais/genética
2.
Int J Mol Sci ; 22(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803557

RESUMO

Marchigian Sardinian alcohol-preferring (msP) rats serve as a unique model of heightened alcohol preference and anxiety disorders. Their innate enhanced stress and poor stress-coping strategies are driven by a genetic polymorphism of the corticotropin-releasing factor receptor 1 (CRF1) in brain areas involved in glucocorticoid signaling. The activation of glucocorticoid receptors (GRs) regulates the stress response, making GRs a candidate target to treat stress and anxiety. Here, we examined whether mifepristone, a GR antagonist known to reduce alcohol drinking in dependent rats, decreases innate symptoms of anxiety in msPs. Male and female msPs were compared to non-selected Wistar counterparts across three separate behavioral tests. We assessed anxiety-like behavior via the novelty-induced hypophagia (NIH) assay. Since sleep disturbances and hyperarousal are common features of stress-related disorders, we measured sleeping patterns using the comprehensive lab monitoring system (CLAMS) and stress sensitivity using acoustic startle measures. Rats received an acute administration of vehicle or mifepristone (60 mg/kg) 90 min prior to testing on NIH, acoustic startle response, and CLAMS. Our results revealed that both male and female msPs display greater anxiety-like behaviors as well as enhanced acoustic startle responses compared to Wistar counterparts. Male msPs also displayed reduced sleeping bout duration versus Wistars, and female msPs displayed greater acoustic startle responses versus male msPs. Importantly, the enhanced anxiety-like behavior and startle responses were not reduced by mifepristone. Together, these findings suggest that increased expression of stress-related behaviors in msPs are not solely mediated by acute activation of GRs.


Assuntos
Ansiedade/patologia , Comportamento Animal , Mifepristona/farmacologia , Receptores de Glucocorticoides/antagonistas & inibidores , Animais , Ansiedade/complicações , Ansiedade/fisiopatologia , Nível de Alerta/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Feminino , Masculino , Ratos Wistar , Receptores de Glucocorticoides/metabolismo , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/fisiopatologia
3.
Int J Mol Sci ; 22(7)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807481

RESUMO

Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRß, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRß has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRß actions are restricted to its dominant-negative effects on GRα-mediated responses, GRß has been shown to have intrinsic activities and "directly" regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRß has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRß-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRß and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.


Assuntos
Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/fisiologia , Processamento Alternativo/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Humanos , Isoformas de Proteínas
4.
Nat Commun ; 12(1): 2239, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854063

RESUMO

Enhancers are transcription factor platforms that synergize with promoters to control gene expression. Here, we investigate enhancers that activate gene expression several hundred-fold exclusively in the lactating mouse mammary gland. Using ChIP-seq for activating histone marks and transcription factors, we identify two candidate enhancers and one super-enhancer in the Csn1s2b locus. Through experimental mouse genetics, we dissect the lactation-specific distal enhancer bound by the mammary-enriched transcription factors STAT5 and NFIB and the glucocorticoid receptor. While deletions of canonical binding motifs for NFIB and STAT5, individually or combined, have a limited biological impact, a non-canonical STAT5 site is essential for enhancer activity during lactation. In contrast, the intronic enhancer contributes to gene expression only in late pregnancy and early lactation, possibly by interacting with the distal enhancer. A downstream super-enhancer, which physically interacts with the distal enhancer, is required for the functional establishment of the Csn1s2b promoter and gene activation. Lastly, NFIB binding in the promoter region fine-tunes Csn1s2b expression. Our study provides comprehensive insight into the anatomy and biology of regulatory elements that employ the JAK/STAT signaling pathway and preferentially activate gene expression during lactation.


Assuntos
Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Lactação/genética , Glândulas Mamárias Animais/metabolismo , Camundongos/genética , Animais , Citocinas/metabolismo , Feminino , Lactação/metabolismo , Camundongos/metabolismo , Fatores de Transcrição NFI/genética , Fatores de Transcrição NFI/metabolismo , Gravidez , Regiões Promotoras Genéticas , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais
5.
Mol Cell ; 81(7): 1484-1498.e6, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33561389

RESUMO

Transcription factors (TFs) regulate gene expression by binding to specific consensus motifs within the local chromatin context. The mechanisms by which TFs navigate the nuclear environment as they search for binding sites remain unclear. Here, we used single-molecule tracking and machine-learning-based classification to directly measure the nuclear mobility of the glucocorticoid receptor (GR) in live cells. We revealed two distinct and dynamic low-mobility populations. One accounts for specific binding to chromatin, while the other represents a confinement state that requires an intrinsically disordered region (IDR), implicated in liquid-liquid condensate subdomains. Further analysis showed that the dwell times of both subpopulations follow a power-law distribution, consistent with a broad distribution of affinities on the GR cistrome and interactome. Together, our data link IDRs with a confinement state that is functionally distinct from specific chromatin binding and modulates the transcriptional output by increasing the local concentration of TFs at specific sites.


Assuntos
Proteínas Intrinsicamente Desordenadas/química , Receptores de Glucocorticoides/química , Fatores de Transcrição/química , Animais , Feminino , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Camundongos , Ratos , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Cancer Sci ; 112(5): 1899-1910, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33619826

RESUMO

Enzalutamide (Enz) is a second-generation androgen receptor (AR) antagonist for castration-resistant prostate cancer (CRPC) therapy, and it prolongs survival time in these patients. However, during Enz treatment, CRPC patients usually acquire resistance to Enz and often show cross-resistance to other AR signaling inhibitors. Although glucocorticoid receptor (GR) is involved in this resistance, the role of GR has not yet been clarified. Here, we report that chronic Enz treatment induced GR-mediated glucose transporter 4 (GLUT4) upregulation, and that upregulation was associated with resistance to Enz and other AR signaling inhibitors. Additionally, inhibition of GLUT4 suppressed cell proliferation in Enz-resistant prostate cancer cells, which recovered from Enz resistance and cross-resistance without changes in GR expression. Thus, a combination of Enz and a GLUT4 inhibitor could be useful in Enz-resistant CRPC patients.


Assuntos
Antineoplásicos/uso terapêutico , Transportador de Glucose Tipo 4/metabolismo , Feniltioidantoína/análogos & derivados , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores de Glucocorticoides/metabolismo , Antagonistas de Receptores de Andrógenos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Transportador de Glucose Tipo 4/antagonistas & inibidores , Humanos , Masculino , Feniltioidantoína/uso terapêutico , Receptores Androgênicos/metabolismo , Regulação para Cima
7.
Nucleic Acids Res ; 49(4): 1951-1971, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33524141

RESUMO

Glucocorticoid receptor (GR) is an essential transcription factor (TF), controlling metabolism, development and immune responses. SUMOylation regulates chromatin occupancy and target gene expression of GR in a locus-selective manner, but the mechanism of regulation has remained elusive. Here, we identify the protein network around chromatin-bound GR by using selective isolation of chromatin-associated proteins and show that the network is affected by receptor SUMOylation, with several nuclear receptor coregulators and chromatin modifiers preferring interaction with SUMOylation-deficient GR and proteins implicated in transcriptional repression preferring interaction with SUMOylation-competent GR. This difference is reflected in our chromatin binding, chromatin accessibility and gene expression data, showing that the SUMOylation-deficient GR is more potent in binding and opening chromatin at glucocorticoid-regulated enhancers and inducing expression of target loci. Blockage of SUMOylation by a SUMO-activating enzyme inhibitor (ML-792) phenocopied to a large extent the consequences of GR SUMOylation deficiency on chromatin binding and target gene expression. Our results thus show that SUMOylation modulates the specificity of GR by regulating its chromatin protein network and accessibility at GR-bound enhancers. We speculate that many other SUMOylated TFs utilize a similar regulatory mechanism.


Assuntos
Cromatina/metabolismo , Receptores de Glucocorticoides/metabolismo , Sumoilação , Sítios de Ligação , Regulação da Expressão Gênica , Células HEK293 , Humanos , Correpressor 1 de Receptor Nuclear/metabolismo , Coativador 1 de Receptor Nuclear , Mapeamento de Interação de Proteínas , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sumoilação/efeitos dos fármacos
8.
Nat Commun ; 12(1): 828, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547294

RESUMO

The co-chaperone p23 is a central part of the Hsp90 machinery. It stabilizes the closed conformation of Hsp90, inhibits its ATPase and is important for client maturation. Yet, how this is achieved has remained enigmatic. Here, we show that a tryptophan residue in the proximal region of the tail decelerates the ATPase by allosterically switching the conformation of the catalytic loop in Hsp90. We further show by NMR spectroscopy that the tail interacts with the Hsp90 client binding site via a conserved helix. This helical motif in the p23 tail also binds to the client protein glucocorticoid receptor (GR) in the free and Hsp90-bound form. In vivo experiments confirm the physiological importance of ATPase modulation and the role of the evolutionary conserved helical motif for GR activation in the cellular context.


Assuntos
Adenilil Imidodifosfato/química , Proteínas de Choque Térmico HSP90/química , Chaperonas Moleculares/química , Prostaglandina-E Sintases/química , Receptores de Glucocorticoides/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/química , Adenilil Imidodifosfato/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Simulação de Dinâmica Molecular , Mutação , Ressonância Magnética Nuclear Biomolecular , Prostaglandina-E Sintases/genética , Prostaglandina-E Sintases/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
9.
Am J Respir Cell Mol Biol ; 64(4): 453-464, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33493091

RESUMO

Fibroblast activation is transient in successful wound repair but persistent in fibrotic pathologies. Understanding fibroblast deactivation during successful wound healing may provide new approaches to therapeutically reverse fibroblast activation. To characterize the gene programs that accompany fibroblast activation and reversal during lung fibrosis resolution, we used RNA sequencing analysis of flow sorted Col1α1-GFP-positive and CD45-, CD31-, and CD326-negative cells isolated from the lungs of young mice exposed to bleomycin. We compared fibroblasts isolated from control mice with those isolated at Days 14 and 30 after bleomycin exposure, representing the peak of extracellular matrix deposition and an early stage of fibrosis resolution, respectively. Bleomycin exposure dramatically altered fibroblast gene programs at Day 14. Principal component and differential gene expression analyses demonstrated the predominant reversal of these trends at Day 30. Upstream regulator and pathway analyses of reversing "resolution" genes identified novel candidate antifibrotic genes and pathways. Two genes from these analyses that were decreased in expression at Day 14 and reversed at Day 30, Aldh2 and Nr3c1, were selected for further analysis. Enhancement of endogenous expression of either gene by CRISPR activation in cultured human idiopathic pulmonary fibrosis fibroblasts was sufficient to reduce profibrotic gene expression, fibronectin deposition, and collagen gel compaction, consistent with roles for these genes in fibroblast deactivation. This combination of RNA sequencing analysis of freshly sorted fibroblasts and hypothesis testing in cultured idiopathic pulmonary fibrosis fibroblasts offers a path toward identification of novel regulators of lung fibroblast deactivation, with potential relevance to understanding fibrosis resolution and its failure in human disease.


Assuntos
Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Aldeído-Desidrogenase Mitocondrial/genética , Aldeído-Desidrogenase Mitocondrial/metabolismo , Animais , Bleomicina , Sistemas CRISPR-Cas , Células Cultivadas , Modelos Animais de Doenças , Fibroblastos/patologia , Edição de Genes , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Camundongos Transgênicos , RNA-Seq , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Remissão Espontânea , Transdução de Sinais , Fatores de Tempo , Transcriptoma
10.
Nat Chem Biol ; 17(3): 307-316, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33510451

RESUMO

Glucocorticoids display remarkable anti-inflammatory activity, but their use is limited by on-target adverse effects including insulin resistance and skeletal muscle atrophy. We used a chemical systems biology approach, ligand class analysis, to examine ligands designed to modulate glucocorticoid receptor activity through distinct structural mechanisms. These ligands displayed diverse activity profiles, providing the variance required to identify target genes and coregulator interactions that were highly predictive of their effects on myocyte glucose disposal and protein balance. Their anti-inflammatory effects were linked to glucose disposal but not muscle atrophy. This approach also predicted selective modulation in vivo, identifying compounds that were muscle-sparing or anabolic for protein balance and mitochondrial potential. Ligand class analysis defined the mechanistic links between the ligand-receptor interface and ligand-driven physiological outcomes, a general approach that can be applied to any ligand-regulated allosteric signaling system.


Assuntos
Anti-Inflamatórios/farmacologia , Transportador de Glucose Tipo 4/genética , Atrofia Muscular/tratamento farmacológico , Receptores de Glucocorticoides/química , Transdução de Sinais/efeitos dos fármacos , Células A549 , Regulação Alostérica , Animais , Anti-Inflamatórios/síntese química , Linhagem Celular Transformada , Regulação da Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Humanos , Lipopolissacarídeos/administração & dosagem , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Ratos , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Relação Estrutura-Atividade
11.
Molecules ; 25(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352739

RESUMO

Ciclesonide is an FDA-approved glucocorticoid used to treat asthma and allergic rhinitis. However, whether it has anticancer and anti-cancer stem cell (CSC) effects is unknown. This study focused on investigating the effect of ciclesonide on breast cancer and CSCs and determining its underlying mechanism. Here, we showed that ciclesonide inhibits breast cancer and CSC formation. Similar glucocorticoids-dexamethasone and prednisone-did not inhibit CSC formation. Ciclesonide-induced glucocorticoid receptor (GR) degradation was dependent on ubiquitination. We showed via GR small interfering RNA (siRNA) that GR plays an important role in CSC formation. We showed via western blot and immunofluorescence assays that ciclesonide reduces the nuclear level of GR. The GR antagonist RU-486 also inhibited CSC formation. Ciclesonide reduced the protein level of the Hippo transducer Yes-associated protein (YAP). GR siRNA induced a decrease in YAP protein expression and inhibited mammosphere formation. The YAP inhibitor verteporfin inhibited CSC formation and transcription of the connective tissue growth factor and cysteine-rich protein 61 genes. The GR/YAP1 pathway regulated breast CSC formation. We showed that the GR/YAP signaling pathway regulates breast CSC formation and revealed a new approach for targeting GR and YAP to inhibit CSC formation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antiasmáticos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Pregnenodionas/farmacologia , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Proteína Rica em Cisteína 61/metabolismo , Glucocorticoides/metabolismo , Humanos , Células MCF-7 , Células-Tronco Neoplásicas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , RNA Interferente Pequeno/metabolismo , Verteporfina/metabolismo
12.
Aging (Albany NY) ; 13(2): 2436-2458, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33316780

RESUMO

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease characterized by glucose metabolic disorders, and gluconeogenesis inhibiting is a promisingly therapeutic strategy for T2DM. Glucocorticoid receptor (GR) is tightly implicated in the regulation of gluconeogenesis, although the underlying mechanism remains obscure. Here, we discovered that small molecule, 5-chloro-N-[4-chloro-3-(trifluoromethyl)phenyl]thiophene-2-sulfonamide (FX5) as a new non-steroidal GR antagonist efficiently ameliorated glucose homeostasis in db/db and HFD/STZ-induced T2DM mice. The mechanism underlying the suppression of FX5 against gluconeogenesis was highly investigated. FX5 suppressed gluconeogenetic genes G6Pase and PEPCK in mouse primary hepatocytes and liver tissues of T2DM mice. Results of mammalian one-hybrid and transactivation as well as nuclear translocation assays totally evaluated the antagonistic features of FX5 against GR. Moreover, siRNA and overexpression related assays verified that FX5 alleviated gluconeogenesis either directly by antagonizing GR or indirectly through GR/HNF4α/miR122-5p signaling pathway. Our work has presented a new mode for GR antagonist in the regulation of gluconeogenesis, which is expected to highlight the potential of FX5 in the treatment of T2DM.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Antagonistas de Hormônios/farmacologia , Receptores de Glucocorticoides/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Antagonistas de Hormônios/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , MicroRNAs/metabolismo , Receptores de Glucocorticoides/metabolismo
13.
Mol Cell ; 80(2): 279-295.e8, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33065020

RESUMO

The PTEN tumor suppressor controls cell death and survival by regulating functions of various molecular targets. While the role of PTEN lipid-phosphatase activity on PtdIns(3,4,5)P3 and inhibition of PI3K pathway is well characterized, the biological relevance of PTEN protein-phosphatase activity remains undefined. Here, using knockin (KI) mice harboring cancer-associated and functionally relevant missense mutations, we show that although loss of PTEN lipid-phosphatase function cooperates with oncogenic PI3K to promote rapid mammary tumorigenesis, the additional loss of PTEN protein-phosphatase activity triggered an extensive cell death response evident in early and advanced mammary tumors. Omics and drug-targeting studies revealed that PI3Ks act to reduce glucocorticoid receptor (GR) levels, which are rescued by loss of PTEN protein-phosphatase activity to restrain cell survival. Thus, we find that the dual regulation of GR by PI3K and PTEN functions as a rheostat that can be exploited for the treatment of PTEN loss-driven cancers.


Assuntos
Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , PTEN Fosfo-Hidrolase/metabolismo , Receptores de Glucocorticoides/metabolismo , Animais , Carcinogênese , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células , Dexametasona/farmacologia , Feminino , Humanos , Isoenzimas/metabolismo , Camundongos , Modelos Biológicos , Mutação/genética , Organoides/patologia , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Estabilidade Proteica , Proteoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
14.
Front Immunol ; 11: 2145, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983174

RESUMO

SARS-CoV-2 infection has recently been declared a pandemic. Some patients showing severe symptoms exhibit drastic inflammation and airway damage. In this study, we re-analyzed published scRNA-seq data of COVID-19 patient bronchoalveolar lavage fluid to further classify and compare immunological features according to the patient's disease severity. Patients with severe symptoms showed DNA damage and apoptotic features of epithelial cells. Our results suggested that epithelial damage was associated with neutrophil infiltration. Myeloid cells of severe patients showed higher expression of proinflammatory cytokines and chemokines such as CXCL8. As a result, neutrophils were abundant in lungs of patients from the severe group. Furthermore, recruited neutrophils highly expressed genes related to neutrophil extracellular traps. Neutrophil-mediated inflammation was regulated by glucocorticoid receptor expression and activity. Based on these results, we suggest that severe COVID-19 symptoms may be determined by differential expression of glucocorticoid receptors and neutrophils.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Interleucina-8/genética , Neutrófilos/imunologia , Pneumonia Viral/imunologia , Receptores de Glucocorticoides/genética , Índice de Gravidade de Doença , Transcriptoma , Adulto , Idoso , Líquido da Lavagem Broncoalveolar/imunologia , Infecções por Coronavirus/virologia , Células Epiteliais/patologia , Armadilhas Extracelulares/imunologia , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Inflamação/imunologia , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , Células Mieloides/imunologia , Infiltração de Neutrófilos/imunologia , Pandemias , Pneumonia Viral/virologia , RNA-Seq , Receptores de Glucocorticoides/metabolismo , Análise de Célula Única/métodos
15.
Proc Natl Acad Sci U S A ; 117(35): 21667-21672, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817534

RESUMO

Extensive pharmacologic, genetic, and epigenetic research has linked the glucocorticoid receptor (GR) to memory processes, and to risk and symptoms of posttraumatic stress disorder (PTSD). In the present study we investigated the epigenetic pattern of 12 genes involved in the regulation of GR signaling in two African populations of heavily traumatized individuals: Survivors of the rebel war in northern Uganda (n = 463) and survivors of the Rwandan genocide (n = 350). The strongest link between regional methylation and PTSD risk and symptoms was observed for NTRK2, which encodes the transmembrane receptor tropomyosin-related kinase B, binds the brain-derived neurotrophic factor, and has been shown to play an important role in memory formation. NTRK2 methylation was not related to trauma load, suggesting that methylation differences preexisted the trauma. Because NTRK2 methylation differences were predominantly associated with memory-related PTSD symptoms, and because they seem to precede traumatic events, we next investigated the relationship between NTRK2 methylation and memory in a sample of nontraumatized individuals (n = 568). We found that NTRK2 methylation was negatively associated with recognition memory performance. Furthermore, fMRI analyses revealed NTRK2 methylation-dependent differences in brain network activity related to recognition memory. The present study demonstrates that NTRK2 is epigenetically linked to memory functions in nontraumatized subjects and to PTSD risk and symptoms in traumatized populations.


Assuntos
Glicoproteínas de Membrana/genética , Receptor trkB/genética , Transtornos de Estresse Pós-Traumáticos/genética , Adulto , Idoso , Encéfalo/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Feminino , Glucocorticoides/metabolismo , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Memória/fisiologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Receptor trkB/metabolismo , Receptores de Glucocorticoides/metabolismo , Fatores de Risco , Ruanda/epidemiologia , Transtornos de Estresse Pós-Traumáticos/metabolismo , Sobreviventes , Uganda/epidemiologia
16.
Life Sci ; 261: 118363, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32861797

RESUMO

AIM: Dexamethasone (DXM) is a synthetic glucocorticoid whose effects in early and terminal adipogenesis have been addressed. In this study, we evaluated if DXM affects adipocyte precursor cells (APCs), priming them for further adipogenic differentiation. For this purpose, we analyzed APCs number and competency after DXM treatment. MATERIALS AND METHODS: Adult male rats were injected for 2 or 7 days with either DXM (30 µg/kg of weight, sc.) or vehicle. Stromal vascular fraction (SVF) cells from retroperitoneal adipose tissue (RPAT) were isolated to quantify APCs by flow cytometry (CD34+/CD45-/CD31-). Also, expression of competency markers (PPARγ2 and Zfp423) was assessed. Additionally, SVF cells from control rats were incubated with DXM (0.25 µM) alone or combined with a mineralocorticoid receptor (MR) antagonist (Spironolactone 10 µM) and/or a glucocorticoid receptor (GR) antagonist (RU486 1 µM) to assess APCs competency and adipocyte differentiation. KEY FINDINGS: APCs from 2 days DXM-treated rats showed increased expression of PPARγ2 and Zfp423 (competency markers), but did not affect APCs percentage by FACS analysis (CD34+/CD45-/CD31-). Additionally, we found that DXM treatment in SVF also increased APCs competency in vitro, predisposing APCs to further adipocyte differentiation. These effects on APCs were abrogated only when both, MR and GR, were blocked. SIGNIFICANCE: Overall, our results suggest that DXM primes APCs for differentiation mainly by enhancing Zfp423 and PPARγ2 expressions. Also, we showed that the inhibition of MR and GR was necessary for the complete abolishment of DXM effects.


Assuntos
Adipócitos/citologia , Adipogenia , Dexametasona/farmacologia , Células-Tronco/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo/citologia , Animais , Biomarcadores/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , PPAR gama/genética , PPAR gama/metabolismo , Ratos Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Espaço Retroperitoneal , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
17.
Nat Commun ; 11(1): 3383, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32636391

RESUMO

The endogenous repair process can result in recovery after acute kidney injury (AKI) with adaptive proliferation of tubular epithelial cells, but repair can also lead to fibrosis and progressive kidney disease. There is currently limited knowledge about transcriptional regulators regulating these repair programs. Herein we establish the enhancer and super-enhancer landscape after AKI by ChIP-seq in uninjured and repairing kidneys on day two after ischemia reperfusion injury (IRI). We identify key transcription factors including HNF4A, GR, STAT3 and STAT5, which show specific binding at enhancer and super-enhancer sites, revealing enhancer dynamics and transcriptional changes during kidney repair. Loss of bromodomain-containing protein 4 function before IRI leads to impaired recovery after AKI and increased mortality. Our comprehensive analysis of epigenetic changes after kidney injury in vivo has the potential to identify targets for therapeutic intervention. Importantly, our data also call attention to potential caveats involved in use of BET inhibitors in patients at risk for AKI.


Assuntos
Lesão Renal Aguda/genética , Elementos Facilitadores Genéticos , Túbulos Renais/citologia , Lesão Renal Aguda/metabolismo , Motivos de Aminoácidos , Animais , Sítios de Ligação , Proliferação de Células , Epigênese Genética , Fibrose , Fator 4 Nuclear de Hepatócito/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas Nucleares , Receptores de Glucocorticoides/metabolismo , Elementos Reguladores de Transcrição , Traumatismo por Reperfusão/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Fatores de Transcrição , Transcrição Genética
18.
Toxicol Appl Pharmacol ; 401: 115118, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32619553

RESUMO

Glucocorticoid receptor (GR) modulates extensive biological and pathological processes including tumor progression through diverse mechanisms. The regulatory effects of dexamethasone (DEX), a synthetic glucocorticoid, as well as its interaction with GR have been recognized beyond hematologic cancers. In the present study, we investigated the anti-cancer efficacy of DEX and the correlation with GR in pancreatic cancer, a most aggressive malignancy threatening human health. The differential levels of GR expression were examined in two human pancreatic cancer cell lines, PANC-1 and SW1990, as well as in xenografts and patient tumor tissues. DEX significantly inhibited colony formation, migration, and tumor growth of PANC-1 cells expressing abundant GR. The underlying mechanisms involved suppression of nuclear factor κB (NF-κB) phosphorylation and down-regulation of epithelial-to-mesenchymal transition (EMT), interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF). The anti-cancer effects of DEX were partially reversed by GR silencing or combinational administration of GR antagonist, RU486. The dose-dependent efficacy of DEX in tumor growth inhibition was also demonstrated in a GR-positive patient-derived xenograft model along with safety in mice. DEX was less potent, however, in SW1990 cells with poor GR expression. Our findings suggest that DEX effectively inhibits pancreatic tumor growth partially through GR activation. The potential correlation between GR expression and anti-cancer efficacy of DEX may have some clinical implications.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Dexametasona/uso terapêutico , Neoplasias Pancreáticas/metabolismo , Receptores de Glucocorticoides/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Células A549 , Animais , Antineoplásicos Hormonais/farmacologia , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/tratamento farmacológico , Carga Tumoral/fisiologia
19.
Aquat Toxicol ; 226: 105562, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32668346

RESUMO

Fish are exposed to steroids of different classes in contaminated waters, but their effects are not sufficiently understood. Here we employed an anti-sense technique using morpholino oligonucleotides to knockdown the glucocorticoid receptors (GRs, GRα and GRß) and androgen receptor (AR) to investigate their role in physiological and transcriptional responses. To this end, zebrafish embryos were exposed to clobetasol propionate (CLO), androstenedione (A4) and mixtures containing different classes of steroids. CLO caused a decrease of spontaneous muscle contraction and increase of heart rate, as well as transcriptional induction of pepck1, fkbp5, sult2st3 and vitellogenin (vtg1) at 24 and/or 48 h post fertilization (hpf). Knockdown of GRs eliminated these effects, while knockdown of AR decreased the ar transcript but caused no expressional changes, except induction of sult2st3 after exposure to A4 at 24 hpf. Exposure to a mixture of 6 steroids comprising progesterone (P4) and three progestins, cyproterone acetate, dienogest, drospirenone, 17ß-estradiol (E2) and CLO caused a significant induction of pepck1, sult2st3, vtg1 and per1a. Knockdown of GRs eliminated the physiological effects and the up-regulation of vtg1, sult2st3, pepck1, fkbp5 and per1a. Thus, as with CLO, responses in mixtures were regulated by GRs independently from the presence of other steroids. Exposure to a mixture comprising A4, CLO, E2 and P4 caused induction of vtg1, cyp19b, sult2st3 and fkbp5. Knockdown of AR had no effect, indicating that regulation of these genes occurred by the GRs and estrogen receptor (ER). Our findings show that in early embryos GRs cause vtg1 and sult2st3 induction in addition to known glucocorticoid target genes. Each steroid receptor regulated its own target genes in steroid mixtures independently from other steroids. However, enhanced expressional induction occurred for vtg1 and fkbp5 in steroid mixtures, indicating an interaction/cross-talk between GRs and ER. These findings have importance for the understanding of molecular effects of steroid mixtures.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Esteroides/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Receptores Androgênicos/genética , Receptores de Glucocorticoides/genética , Transdução de Sinais , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
20.
Nat Commun ; 11(1): 3593, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32681096

RESUMO

During pregnancy, maternal endocrine signals drive fetal development and program the offspring's physiology. A disruption of maternal glucocorticoid (GC) homeostasis increases the child's risk of developing psychiatric disorders later in life. We here show in mice, that the time of day of antenatal GC exposure predicts the behavioral phenotype of the adult offspring. Offspring of mothers receiving GCs out-of-phase compared to their endogenous circadian GC rhythm show elevated anxiety, impaired stress coping, and dysfunctional stress-axis regulation. The fetal circadian clock determines the vulnerability of the stress axis to GC treatment by controlling GC receptor (GR) availability in the hypothalamus. Similarly, a retrospective observational study indicates poorer stress compensatory capacity in 5-year old preterm infants whose mothers received antenatal GCs towards the evening. Our findings offer insights into the circadian physiology of feto-maternal crosstalk and assign a role to the fetal clock as a temporal gatekeeper of GC sensitivity.


Assuntos
Relógios Circadianos/efeitos dos fármacos , Glucocorticoides/efeitos adversos , Exposição Materna/efeitos adversos , Transtornos Mentais/etiologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , Ansiedade , Comportamento/efeitos dos fármacos , Feminino , Glucocorticoides/administração & dosagem , Humanos , Recém-Nascido Prematuro/psicologia , Masculino , Transtornos Mentais/metabolismo , Transtornos Mentais/fisiopatologia , Transtornos Mentais/psicologia , Gravidez , Complicações na Gravidez/tratamento farmacológico , Cuidado Pré-Natal , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo
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