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1.
Mater Sociomed ; 36(1): 40-46, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590598

RESUMO

Background: This study examines the employability and career trajectories of International Hellenic University's (IHU) midwifery students who graduated between 2016 to 2021, with a focus on undergraduate curriculum changes. Objective: To comprehensively examine the post-graduation journey of recent IHU Midwifery graduates. This includes shedding light on their employment trajectories, satisfaction levels, and the practical application of academic knowledge. Through this exploration, the study seeks to inform educational strategies to ensure alignment with the evolving needs of midwifery professionals in Greece. Methods: Online questionnaires that explored post-graduation experiences, perspectives on the study program, and future plans. The questionnaires consisted of a mix of open and closed-ended questions and were completed by 273 recipients. The study was conducted from May to September 2023, with participant anonymity maintained. Statistical analysis was performed using SPSS. Results: This study revealed differences between graduates of the 'old' and 'new' midwifery undergraduate curriculum. There were notable variations in the perceived impact of the six-month internship on employment. The study also highlighted the impact of the COVID-19 pandemic on educational experiences, emphasizing the nuanced challenges faced during clinical practice, practical training, and simulation training. Finally, the self-employed professionals and those employed in the public sector expressed higher satisfaction with the alignment of their employment with their undergraduate studies, than their counterparts in the private sector (p=0.038). Conclusions: Our study offers valuable insights into job placement, knowledge sufficiency, and the impact of the pandemic on midwifery undergraduate education. These findings can guide tailored strategies for improved education and holistic professional development, ultimately enhancing maternal and neonatal care.

2.
Minerva Pediatr (Torino) ; 75(3): 395-399, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-28643993

RESUMO

BACKGROUND: Cathelicidin has been correlated with the pathophysiology of atopic dermatitis (AD). An indirect correlation of vitamin D with the course of the disease has already been reported as it directly affects the levels of cathelicidin. The purpose of the present article is to investigate the impact of vitamin D supplementation on the course of AD. METHODS: We conducted a prospective observational study. The severity of AD was assessed with the clinical tool SCORAD (SCORing Atopic Dermatitis) which is developed by the European Task Force on AD. RESULTS: Fifty children with AD were enrolled and stratified in two groups based on the severity of SCORAD. Children with severe AD (SCORAD Index >40) received higher doses of vitamin D in order to sufficiently reduce the disease (comparable SCORAD Index for children with mild atopic dermatitis). While the baseline SCORAD differed statistically significant level between the two groups of children with AD (P<0.001) this difference disappeared at 20 (P=0.649) days and remained statistically insignificant both at 45 days (P=0.610), and at the end of the administration of treatment (P=0.474). This effect was based on a significant downregulation of the severity of symptoms in the group of children that received 2400 IU of vitamin D. CONCLUSIONS: The findings of our study suggest that vitamin D may be accurately used in current clinical practice for the management of AD. However, the recommended dose should be titrated taking in mind the severity of the disease.


Assuntos
Catelicidinas , Dermatite Atópica , Humanos , Criança , Catelicidinas/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/diagnóstico , Índice de Gravidade de Doença , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Suplementos Nutricionais , Progressão da Doença
3.
Exp Ther Med ; 24(5): 705, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36324612

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic has had a widespread impact on individuals' mental health through indirect psychological and social mechanisms, related to factors such as fear of infection or death, social isolation, lack of social support and financial instability. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has also been associated with the development or recurrence of neuropsychiatric symptoms, both during the acute phase, as well as during the post-acute 'long-COVID' phase. In addition to the COVID-19 survivors with a mental health history that are at a high risk of experiencing a range of neuropsychiatric symptoms following resolution of acute COVID-19, there is accumulating evidence that a diagnosis of COVID-19 may also be associated with new-onset neuropsychiatric morbidity among survivors without pre-existing mental health disorders. In particular, studies investigating the incidence of post-acute neuropsychiatric sequelae, based mostly on retrospective cohort study designs and data from national health registries, have reported the development of new-onset manifestations, including depression, anxiety, psychotic symptoms, sleep disturbances and fatigue. Nevertheless, when COVID-19 survivors were compared with SARS-CoV-2-negative controls and especially survivors of other disorders (such as influenza), the findings regarding the risk of incident neuropsychiatric manifestations varied among studies. While there is evidence of an association between SARS-CoV-2 infection and the subsequent occurrence of new-onset neuropsychiatric symptoms, especially among patients with increased disease severity, further research using methodological approaches less susceptible to confounding bias is required to establish causal relationships.

5.
Front Cell Dev Biol ; 9: 669363, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34055801

RESUMO

Hematopoietic stem cells (HSCs) produce all the terminally differentiated blood cells and are controlled by extracellular signals from the microenvironment, the bone marrow (BM) niche, as well as intrinsic cell signals. Intrinsic signals include the tightly controlled action of signaling pathways, as the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway. Activation of JAK-STAT leads to phosphorylation of members of the STAT family to regulate proliferation, survival, and self-renewal of HSCs. Mutations in components of the JAK-STAT pathway are linked with defects in HSCs and hematologic malignancies. Accumulating mutations in HSCs and aging contribute to leukemia transformation. Here an overview of hematopoiesis, and the role of the JAK-STAT pathway in HSCs and in the promotion of leukemic transformation is presented. Therapeutic targeting of JAK-STAT and clinical implications of the existing research findings are also discussed.

7.
J Clin Med ; 9(1)2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947809

RESUMO

Reactivation of γ-globin is considered a promising approach for the treatment of ß-thalassemia and sickle cell disease. Therapeutic induction of γ-globin expression, however, is fraught with lack of suitable therapeutic targets. The aim of this study was to investigate the effects that treatment with decitabine has on the proteome of human primary erythroid cells from healthy and thalassemic volunteers, as a means of identifying new potential pharmacological targets. Decitabine is a known γ-globin inducer, which is not, however, safe enough for clinical use. A proteomic approach utilizing isobaric tags for relative and absolute quantitation (iTRAQ) analysis, in combination with high-pH reverse phase peptide fractionation followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), was employed to investigate the effects of decitabine treatment. Bioinformatics analysis making use of the Database for Annotation, Visualization and Integrated Discovery (DAVID) was employed for functional annotation of the 192 differentially expressed proteins identified. The data are available via ProteomeXchange with identifier PXD006889. The proteins fall into various biological pathways, such as the NF-κB signaling pathway, and into many functional categories including regulation of cell proliferation, transcription factor and DNA binding, protein stabilization, chromatin modification and organization, and oxidative stress proteins.

8.
Front Oncol ; 9: 594, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31380267

RESUMO

BAFF, APRIL and their receptors regulate the survival, maturation and homeostasis of mature B-cells. Despite the lack of a functional role of BAFF/APRIL system during normal early B-cell development, previous studies indicated a contribution of these molecules in the pathogenesis of B-lineage acute lymphoblastic leukemia (B-ALL). Here, we evaluated the expression of this system in B-ALL and its involvement in spontaneous and drug-induced apoptosis of B-lymphoblasts, taking into consideration the distinct disease subtypes. We found that BAFFR is the most predominant aberrantly expressed receptor in B-ALL and that its expression, along with BCMA and APRIL, positively correlates with the maturation stage of B-lymphoblasts. Moreover, the binding of the E2A-PBX1 chimeric protein to the BAFFR promoter suggests that the transcriptional activator promotes the increase in BAFFR expression observed in about 50% of pre-B-ALL patients carrying the t (1, 19) translocation. BAFF binding to BAFFR led to the processing of NF-κB2 p100 in pre-B ALL cells suggesting that BAFFR can activate the NF-κB2 pathway in pre-B ALL cells. Surprisingly, we found that BAFF treatment promotes the cell death of primary BCR-ABL+ BAFFR+ pre-B-lymphoblasts in adult B-ALL. It also enhances glucocorticoid-induced apoptosis in the E2A-PBX1+ pre-B-ALL cell line 697. These data suggest that BAFF/BAFFR signaling in B-ALL cells differs from normal B cells and that it may affect the pathogenesis of the disease.

9.
Mol Diagn Ther ; 23(2): 223-234, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30712217

RESUMO

Hemoglobinopathies include all genetic diseases of hemoglobin and are grouped into thalassemia syndromes and structural hemoglobin variants. The ß-thalassemias constitute a group of severe anemias with monogenic inheritance, caused by ß-globin gene mutations. This review is focused on omics studies in hemoglobinopathies and mainly ß-thalassemia, and discusses genomic, epigenomic, transcriptomic, proteomic and metabolomic findings. Omics analyses have identified various disease modifiers with an impact on disease severity and efficacy of treatments. These modifiers have contributed to the understanding of globin genes regulation/hemoglobin switching and the development of novel therapies. How omics data and their integration can contribute to efficient patient stratification, therapeutic management, improvements in existing treatments and application of novel personalized therapies is discussed.


Assuntos
Genômica/métodos , Hemoglobinopatias/genética , Epigênese Genética , Edição de Genes , Humanos , Metabolômica , Transcriptoma/genética
10.
J Mol Biochem ; 6(1): 3-12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28775968

RESUMO

BACKGROUND: Many rapid nongenomic glucocorticoid actions are mediated by membrane-bound glucocorticoid receptors (GRs). S-palmitoylation is a lipid post-translational modification that mediates the membrane localization of some steroid receptors. A highly homologous amino acid sequence (663YLCM KTLLL671) is present in the ligand-binding domain of hGRα, suggesting that hGRα might also undergo S-palmitoylation. AIM: To investigate the role of the motif 663YLCMKTLLL671 in membrane localization of the hGRα and in mediating rapid nongenomic glucocorticoid signaling. METHODS AND RESULTS: We showed that the mutant receptors hGRαY663A, hGRαC665A and hGRαLL670/671AA, and the addition of the palmitoylation inhibitor 2-bromopalmitate did not prevent membrane localization of hGRα and co-localization with caveolin-1, and did not influence the biphasic activation of mitogen-activated protein kinase (MAPK) signaling pathway in the early time points. Finally, the hGRα was not shown to undergo S-palmitoylation. CONCLUSIONS: The motif 663YLCMKTLLL671 does not play a role in membrane localization of hGRα and does not mediate the nongenomic glucocorticoid actions.

11.
Nucleic Acids Res ; 45(1): 142-154, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-27651463

RESUMO

STAT5 interacts with other factors to control transcription, and the mechanism of regulation is of interest as constitutive active STAT5 has been reported in malignancies. Here, LSD1 and HDAC3 were identified as novel STAT5a interacting partners in pro-B cells. Characterization of STAT5a, LSD1 and HDAC3 target genes by ChIP-seq and RNA-seq revealed gene subsets regulated by independent or combined action of the factors and LSD1/HDAC3 to play dual role in their activation or repression. Genes bound by STAT5a alone or in combination with weakly associated LSD1 or HDAC3 were enriched for the canonical STAT5a GAS motif, and such binding induced activation or repression. Strong STAT5 binding was seen more frequently in intergenic regions, which might function as distal enhancer elements. Groups of genes bound weaker by STAT5a and stronger by LSD1/HDAC3 showed an absence of the GAS motif, and were differentially regulated based on their genomic binding localization and binding affinities. These genes exhibited increased binding frequency in promoters, and in conjunction with the absence of GAS sites, the data indicate a requirement for stabilization by additional factors, which might recruit LSD1/HDAC3. Our study describes an interaction network of STAT5a/LSD1/HDAC3 and a dual function of LSD1/HDAC3 on STAT5-dependent transcription, defined by protein-protein interactions, genomic binding localization/affinity and motifs.


Assuntos
Linfócitos B/metabolismo , Histona Desacetilases/genética , Histona Desmetilases/genética , Fator de Transcrição STAT5/genética , Transcrição Gênica , Animais , Linfócitos B/citologia , Sítios de Ligação , Linhagem Celular Tumoral , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Histona Desacetilases/metabolismo , Histona Desmetilases/metabolismo , Camundongos , Motivos de Nucleotídeos , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais
12.
Eur J Clin Invest ; 45(12): 1306-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26479047

RESUMO

BACKGROUND: Transient generalized glucocorticoid hypersensitivity is a rare disorder characterized by increased tissue sensitivity to glucocorticoids and compensatory hypo-activation of the hypothalamic-pituitary-adrenal axis. The condition itself and the underlying molecular mechanisms have not been elucidated. OBJECTIVE: To present the clinical manifestations, endocrinologic evaluation and transcriptomic profile in a patient with transient generalized glucocorticoid hypersensitivity. DESIGN AND RESULTS: A 9-year-old girl presented with an 8-month history of clinical manifestations suggestive of Cushing syndrome. Endocrinologic evaluation revealed undetectable 08:00 h ACTH (<1 pg/mL) and cortisol (0·025 µg/dL) concentrations, which remained decreased throughout the 24-h period and did not respond to stimulation with ovine CRH. The disease gradually resolved spontaneously over the ensuing 3 months. Sequencing of the human glucocorticoid receptor gene revealed no mutations or polymorphisms. Western blot analysis in peripheral blood mononuclear cells revealed equal protein expression of hGRα of the patient in the disease and postresolution phases compared with a control subject. Transcriptomic analysis in peripheral blood mononuclear cells in the disease and postresolution phases identified 903 differentially expressed genes. Of these, 106 genes were up-regulated and 797 were down-regulated in the disease compared with the resolution phase. Bioinformatics analysis on the differentially expressed gene networks revealed Nuclear Factor-κB as the predominant transcription factor influencing the expression of the majority of differentially expressed genes. CONCLUSIONS: Our findings indicate that a transient postreceptor defect, or a virus- or bacterium-encoded molecule, may have enhanced glucocorticoid signal transduction, leading to transient generalized glucocorticoid hypersensitivity and hypo-activation of the HPA axis.


Assuntos
Glucocorticoides/genética , Hipersensibilidade/genética , Receptores de Glucocorticoides/genética , Hormônio Adrenocorticotrópico/deficiência , Criança , Feminino , Humanos , Hidrocortisona/deficiência , Remissão Espontânea
14.
PLoS One ; 10(4): e0123522, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856466

RESUMO

Recent evidence supports a role of microRNAs in cancer and psychiatric disorders such as schizophrenia and bipolar disorder, through their regulatory role on the expression of multiple genes. The rather rare co-morbidity of cancer and schizophrenia is an old hypothesis which needs further research on microRNAs as molecules that might exert their oncosuppressive or oncogenic activity in the context of their role in psychiatric disorders. The expression pattern of a variety of different microRNAs was investigated in patients (N = 6) suffering from schizophrenia termed control, patients with a solid tumor (N = 10) and patients with both schizophrenia and tumor (N = 8). miRNA profiling was performed on whole blood samples using the miRCURY LNA microRNA Array technology (6th & 7th generation). A subset of 3 microRNAs showed a statistically significant differential expression between the control and the study groups. Specifically, significant down-regulation of the let-7p-5p, miR-98-5p and of miR-183-5p in the study groups (tumor alone and tumorand schizophrenia) was observed (p<0.05). The results of the present study showed that let-7, miR-98 and miR-183 may play an important oncosuppressive role through their regulatory impact in gene expression irrespective of the presence of schizophrenia, although a larger sample size is required to validate these results. Nevertheless, further studies are warranted in order to highlight a possible role of these and other micro-RNAs in the molecular pathways of schizophrenia.


Assuntos
MicroRNAs/biossíntese , Neoplasias/sangue , Esquizofrenia/sangue , Idoso , Biomarcadores/sangue , Biomarcadores Tumorais , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Neoplasias/patologia , Esquizofrenia/patologia
15.
J Clin Endocrinol Metab ; 99(5): E902-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24483153

RESUMO

CONTEXT: Primary generalized glucocorticoid resistance is a rare genetic disorder characterized by generalized, partial, target-tissue insensitivity to glucocorticoids. The molecular basis of the condition has been ascribed to inactivating mutations in the human glucocorticoid receptor (hGR) gene. OBJECTIVE: The objective of the study was to present three new cases caused by a novel mutation in the hGR gene and to delineate the molecular mechanisms through which the mutant receptor impairs glucocorticoid signal transduction. DESIGN AND RESULTS: The index case (father) and his two daughters presented with increased urinary free cortisol excretion and resistance of the hypothalamic-pituitary-adrenal axis to dexamethasone suppression in the absence of clinical manifestations suggestive of Cushing syndrome. All subjects harbored a novel, heterozygous, point mutation (T→G) at nucleotide position 1724 of the hGR gene, which resulted in substitution of valine by glycine at amino acid 575 of the receptor. Compared with the wild-type receptor, the hGRαV575G demonstrated a significant (33%) reduction in its ability to transactivate the mouse mammary tumor virus promoter in response to dexamethasone, a 50% decrease in its affinity for the ligand, and a 2.5-fold delay in nuclear translocation. Although it did not exert a dominant negative effect on the wild-type receptor and preserved its ability to bind to DNA, hGRαV575G displayed significantly enhanced (∼80%) ability to transrepress the nuclear factor-κΒ signaling pathway. Finally, the mutant receptor hGRαV575G demonstrated impaired interaction with the LXXLL motif of the glucocorticoid receptor-interacting protein 1 coactivator in vitro and in computer-based structural simulation via its defective activation function-2 (AF-2) domain. CONCLUSIONS: The natural mutant receptor hGRαV575G causes primary generalized glucocorticoid resistance by affecting multiple steps in the glucocorticoid signaling cascade, including the affinity for the ligand, the time required for nuclear translocation, and the interaction with the glucocorticoid-interacting protein-1 coactivator.


Assuntos
Sistema Hipotálamo-Hipofisário/metabolismo , Erros Inatos do Metabolismo/genética , Sistema Hipófise-Suprarrenal/metabolismo , Mutação Puntual , Receptores de Glucocorticoides/deficiência , Receptores de Glucocorticoides/genética , Adulto , Idoso , Sítios de Ligação/genética , Feminino , Humanos , Masculino , Erros Inatos do Metabolismo/metabolismo , Pessoa de Meia-Idade , Receptores de Glucocorticoides/metabolismo
16.
Gene Expr Patterns ; 14(1): 19-29, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24140890

RESUMO

The nuclear casein kinase and cyclin-dependent kinase substrate 1 (NUCKS) is a highly phosphorylated nuclear protein that is overexpressed in many types of cancer. The flexibility of NUCKS and its extensive posttranslational modifications indicate that it is multifunctional, and its expression in most cell types suggests a housekeeping function. However, spatiotemporal expression of the Nucks protein during rodent development has not been reported. Thus, we investigated the expression of both the Nucks mRNA and protein during rat and mouse development by immunohistochemistry, in situ hybridization, Western immunoblotting, and reverse-transcription PCR analysis. We also used BLAST analysis against expressed sequence tag databases to determine whether a NUCKS homologue is expressed in invertebrate organisms. We found that Nucks expression increased during the initial stages of embryonic development, and then gradually decreased until birth in all tissues except the nervous tissue and muscle fibers. Interestingly, the expression of Nucks was very strong in migrating neural crest cells at E13.5 and ectoderm-derived tissues. In most tissues analyzed, the levels of Nucks correlated with the levels of Bax and activated caspase-3, which are indicative of apoptosis. Moreover, Nucks was upregulated very early during neuronal apoptosis in vitro. Expression analysis revealed that no transcript with close homology to the Nucks gene was present in invertebrates. The expression of Nucks in both proliferating and quiescent cells and its correlation with Bax levels and apoptosis strongly suggest that Nucks plays complex roles in cell homeostasis. Furthermore, the lack of homology in invertebrate organisms indicates a specific role for Nucks in vertebrate embryogenesis.


Assuntos
Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário , Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Apoptose , Sequência de Bases , Caspase 3/metabolismo , Embrião de Mamíferos/citologia , Evolução Molecular , Etiquetas de Sequências Expressas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Dados de Sequência Molecular , Fibras Musculares Esqueléticas/metabolismo , Tecido Nervoso/embriologia , Proteínas Nucleares/química , Fosfoproteínas/química , Gravidez , Ratos , Ratos Wistar , Proteína X Associada a bcl-2/metabolismo
17.
PLoS One ; 8(10): e76155, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24155890

RESUMO

STAT5 controls essential cellular functions and is encoded by two genes, Stat5a and Stat5b. To provide insight to the mechanisms linking hematologic malignancy to STAT5 activation/regulation of target genes, we identified STAT5 target genes and focused on Dpf3 gene, which encodes for an epigenetic factor. Dpf3 expression was induced upon IL-3 stimulation in Ba/F3 cells, while strong binding of both STAT5a and STAT5b was detected in its promoter. Reduced expression of Dpf3 was detected in Ba/F3 cells with Stat5a and Stat5b knock-down, suggesting that this gene is positively regulated by STAT5, upon IL-3 stimulation. Furthermore, this gene was significantly up-regulated in CLL patients, where DPF3 gene/protein up-regulation and strong STAT5 binding to the DPF3 promoter, correlated with increased STAT5 activation, mainly in non-malignant myeloid cells (granulocytes). Our findings provide insights in the STAT5 dependent transcriptional regulation of Dpf3, and demonstrate for the first time increased STAT5 activation in granulocytes of CLL patients. Novel routes of investigation are opened to facilitate the understanding of the role of STAT5 activation in the communication between non-malignant myeloid and malignant B-cells, and the functions of STAT5 target genes networks in CLL biology.


Assuntos
Proteínas de Ligação a DNA/genética , Leucemia Linfocítica Crônica de Células B/genética , Fator de Transcrição STAT5/metabolismo , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Biblioteca Gênica , Genoma Humano/genética , Células HEK293 , Humanos , Interleucina-3/farmacologia , Camundongos , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
18.
J Clin Endocrinol Metab ; 98(4): E790-5, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23426617

RESUMO

CONTEXT: Primary generalized glucocorticoid resistance is a rare genetic condition characterized by partial end-organ insensitivity to glucocorticoids. Most affected subjects present with clinical manifestations of mineralocorticoid and androgen excess. The condition has been associated with inactivating mutations in the human glucocorticoid receptor (hGR) gene, which impair the molecular mechanisms of hGRα action, thereby reducing tissue sensitivity to glucocorticoids. OBJECTIVE: ΤHE aim of our study was to investigate the molecular mechanisms through which one previously described natural heterozygous V423A mutation, the second mutation detected in the DNA-binding domain (DBD) of the hGRα, affects glucocorticoid signal transduction. DESIGN AND RESULTS: Compared with the wild-type receptor, hGRαV423A demonstrated a 72% reduction in its ability to transactivate the glucocorticoid-inducible mouse mammary tumor virus promoter in response to dexamethasone. The hGRαV423A receptor showed a significant reduction in its ability to bind to glucocorticoid-response elements of glucocorticoid-responsive genes, owing to structural alterations of the DBD confirmed by computer-based structural analysis. In addition, hGRαV423A demonstrated a 2.6-fold delay in nuclear translocation following exposure to the ligand, although it did not exert a dominant negative effect on the wild-type hGRα, had a similar affinity to the ligand with the wild-type receptor, and displayed a normal interaction with the GRIP1 coactivator in vitro. CONCLUSIONS: The natural mutant receptor hGRαV423A causes primary generalized glucocorticoid resistance by affecting multiple steps in the cascade of glucocorticoid receptor action, which primarily involve decreased ability to bind to target glucocorticoid response elements and delayed translocation into the nucleus.


Assuntos
DNA/metabolismo , Erros Inatos do Metabolismo/genética , Mutação Puntual , Domínios e Motivos de Interação entre Proteínas/genética , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/genética , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Cricetinae , Células HCT116 , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Mutação Puntual/fisiologia , Ligação Proteica/genética , Domínios e Motivos de Interação entre Proteínas/fisiologia , Receptores de Glucocorticoides/deficiência , Relação Estrutura-Atividade
19.
Sci Signal ; 5(248): pt13, 2012 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-23112345

RESUMO

Signal transducers and activators of transcription (STATs) are implicated in physiological cellular processes, stress-related responses, and malignancies. This Presentation provides an overview on STATs, focusing on STAT5, and describes an in vivo biotinylation methodology applied in mammalian cells for identification of STAT5-containing protein complexes and STAT5 target genes. Our results show that in vivo biotinylation can be used efficiently to elucidate the complex STAT5-dependent transcriptional mechanisms.


Assuntos
Biotinilação/métodos , Complexos Multiproteicos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Fator de Transcrição STAT5/metabolismo , Estresse Fisiológico , Transcrição Gênica , Animais , Humanos
20.
Eur J Endocrinol ; 166(4): 695-702, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22223701

RESUMO

OBJECTIVE: The polycystic ovary syndrome (PCOS) is a common and complex disease with unclear pattern of inheritance, characterized by an androgen excess, while hyperinsulinemia and insulin resistance (IR) are common features of the syndrome. The angiotensin I converting enzyme (ACE) insertion (I)/deletion (D) gene polymorphism was proved to be involved in many pathophysiological conditions, including hypertension and IR. DESIGN: The purpose of this study was to evaluate the involvement of the ACE gene polymorphism in the pathogenesis of PCOS. METHODS: In a case-control association study involving 801 PCOS women and 266 healthy controls, hormonal determinations and ACE polymorphism genotyping were performed. The PCOS women were classified into three groups: Group A presented biochemical hyperandrogenism, combined with anovulation and polycystic ovarian morphology; Group B, clinical hyperandrogenism combined with anovulation and polycystic ovarian morphology; and Group C, chronic anovulation and polycystic ovarian morphology. RESULTS: A significant increase in the frequency of the DI genotype of the ACE polymorphism was detected in PCOS women as a whole (P=0.035), in PCOS Group A (P=0.039) and Group B (P=0.010), while there was no difference in Group C (P=0.939). Significant difference was also observed in hyperandrogenic PCOS women as a whole (Group A+B) (P=0.017). The II genotype was positively correlated with HOMA-IR and QUICKI and with fasting insulin and glucose/insulin ratio in these groups. CONCLUSIONS: The association study of the ACE I/D polymorphism in PCOS women demonstrates an increase in the DI genotype incidence and an association of the II genotype with IR.


Assuntos
Mutação INDEL , Resistência à Insulina/genética , Peptidil Dipeptidase A/genética , Síndrome do Ovário Policístico/genética , Polimorfismo Genético , Adolescente , Adulto , Glicemia/análise , Glicemia/metabolismo , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Mutação INDEL/fisiologia , Insulina/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Polimorfismo Genético/fisiologia , Adulto Jovem
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