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1.
Leuk Res Rep ; 18: 100340, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958243

RESUMO

Case of a patient with acute myeloid leukemia (AML) positive for mutations in both genes NPM1 and FLT3-ITD who underwent two allogeneic haematopoietic stem cell transplants (HSCT); the second allograft one was followed by extramedullary relapse (granulocytic sarcoma of right breast), with blast cells positive for FLT3-ITDmutation.  Treatment with Gilteritinib, a second generation selective oral type I FLT3 inhibitor, was started after the second HSCT with complete regression of breast granulocytic sarcoma in absence of hematological and extra hematologic toxicity. We conclude that Gilteritinib can represent an effective therapy for extra hematologic relapse, with acceptable toxicity and outpatient management.

2.
Rev Sci Instrum ; 92(4): 043533, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243454

RESUMO

We have analyzed the electrical characteristics of a plug probe as a function of the orientation relative to the local magnetic field. Our aim was to demonstrate that the probe characteristic, besides a better evaluation of the plasma potential, retains the capability to reliably estimate the electron temperature and density. This feature could be exploited with a multi-pin probe to measure simultaneously the fluctuations of all plasma parameters.

3.
Rev Sci Instrum ; 92(2): 023512, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648151

RESUMO

We discuss the measurement of the electric field drift (E→xB→ velocity) and its spatial derivatives in a low temperature magnetized plasma by means of a suitably arranged multi-pin Langmuir probe. Results are presented relating the properties of the velocity field and its electrostatic fluctuations. In particular, we have measured components of the non-linear terms in the fluid magnetohydrodynamics equation.

4.
Sci Rep ; 8(1): 10318, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-29985450

RESUMO

Principal research on energy from thermonuclear fusion uses Deuterium-Tritium plasmas magnetically trapped in toroidal devices. As major scientific problem for an economic (i.e., really feasible) reactor, we must understand how to lead strongly heated plasmas to sustain a high fusion gain while large fraction of current is self-produced via the presence of strong pressure gradient. To suppress turbulent eddies that impair thermal insulation and pressure tight of the plasma, current drive (CD) is necessary. However, tools envisaged so far in ITER (International Thermonuclear Experiment Rector) are unable accomplishing this task that requires efficiently and flexibly matching the natural current profiles of plasma. Consequently, viability of a thermonuclear reactor should be problematic. Multi-megawatt radio-frequency (RF) power coupled to plasma would produce the necessary CD, but modelling results based on previous understanding found difficult the extrapolation of this CD concept to reactor conditions of high temperature plasma, and greater flexibility of method would also be required. Here we present new model results based on standard quasilinear (QL) theory that allow establish conditions to drive efficiently and flexibly the RF-driven current at large radii of the plasma column, as necessary for the goal of a reactor.

5.
Methods Enzymol ; 590: xv-xix, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28411653
6.
Phys Rev E ; 93(3): 033202, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27078470

RESUMO

The authors suggest a model to simulate the dynamics of ions in a supersonic plasma jet. The model relies on experimental argon ion, Ar(+), energy distribution functions measured by a quadrupole mass spectrometer at different positions along the central axis of a supersonic argon plasma jet. The latter is generated by the pressure difference between two vacuum chambers connected through a converging nozzle: a high-pressure chamber (P ≃ 3.20 Pa), where an inductively coupled argon plasma discharge is maintained, and a lower-pressure one (P ≃ 0.11 Pa), where the plasma jet expands. The model is based on the integration of the equations of motion of a single Ar(+), moving along the supersonic jet in a reference system in which neutral species are at rest. Ar(+)-Ar induced dipole interactions are treated using a 12-4 Lennard-Jones potential. The resulting collisions are considered to be purely elastic, and in addition to them, we allow for charge transfer processes. The energy and position of 1000 Ar(+) were calculated, using an integration time step of 10 ps for ion trajectories ranging from 5 mm to 20 mm from the nozzle, well inside the spatial extension of the supersonic jet. The numerically obtained ion energy distribution functions agree remarkably well with the experimental measurements. From our calculations we can draw conclusions about the energy loss and the mean free paths along the jet. In particular, we can distinguish between processes with and without charge transfer, allowing us to determine the effect of charge exchange phenomena in which the ion changes its nature. The calculated mean free paths were used to evaluate the effective cross sections for momentum transfer and charge transfer collisions, valid for ion energies in the range (0.5-10) eV, in very good agreement with those reported in the literature.

7.
Chem Commun (Camb) ; 52(12): 2593-6, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26752084

RESUMO

A modular, general method for trapping enzymes within the voids of paper, without chemical activation of cellulose, is reported. Glucose oxidase and peroxidase were crosslinked with poly(acrylic acid) via carbodiimide chemistry, producing 3-dimensional networks interlocked in cellulose fibers. Interlocking prevented enzyme activity loss and enhanced the washability and stability.


Assuntos
Glucose Oxidase/química , Papel , Peroxidases/química , Polímeros/química , Cinética , Estrutura Secundária de Proteína
8.
Curr Mol Med ; 15(10): 990-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26592242

RESUMO

Aberrant activation of Wnt/ß-catenin signaling pathway is commonly associated to cancer development. However, molecular mechanisms controlling Wnt/ß-catenin signaling pathway have been clarified only in part. Here, we show that ß-catenin is differently modulated in patients with multiple sclerosis (MS), displaying that different pharmacological treatments used for clinical MS management cause different nuclear expression levels of ß-catenin. Proteins extracted by peripheral blood mononuclear cells were assessed to evaluate the western blot expression levels of ß-catenin. Analyzing our results, we realized that ß-catenin is totally inhibited by Natalizumab and could have a role in MS management. This could offer new promising studies focused on the possible therapeutic control of ß-catenin translocation.


Assuntos
Núcleo Celular/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Natalizumab/uso terapêutico , beta Catenina/antagonistas & inibidores , Adulto , Estudos de Casos e Controles , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Interferon beta-1a/uso terapêutico , Interferon beta-1b/uso terapêutico , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Transporte Proteico/efeitos dos fármacos , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
9.
Rev Sci Instrum ; 86(2): 026103, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25725896

RESUMO

Background Oriented Schlieren (BOS) is an optical technique sensitive to the first spatial derivative of the refractive index inside a light-transmitting medium. Compared to other Schlieren-like techniques, BOS is more versatile and allows to capture bi-dimensional gradients rather than just one spatial component. We propose to adopt BOS for studying the capabilities of surface dielectric barrier discharges to work like plasma actuators in flow control applications. The characteristics of the BOS we implemented at this purpose are discussed, together with few results concerning the ionic wind produced by the discharge in absence of an external airflow.

10.
Cell Death Differ ; 22(1): 118-30, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25168242

RESUMO

The transcription factor p53 regulates the expression of genes crucial for biological processes such as cell proliferation, metabolism, cell repair, senescence and apoptosis. Activation of p53 also suppresses neoplastic transformations, thereby inhibiting the growth of mutated and/or damaged cells. p53-binding proteins, such as mouse double minute 2 homolog (MDM2), inhibit p53 activation and thus regulate p53-mediated stress responses. Here, we found that long glucocorticoid-induced leucine zipper (L-GILZ), a recently identified isoform of GILZ, activates p53 and that the overexpression of L-GILZ in p53(+/+) HCT116 human colorectal carcinoma cells suppresses the growth of xenografts in mice. In the presence of both p53 and MDM2, L-GILZ binds preferentially to MDM2 and interferes with p53/MDM2 complex formation, making p53 available for downstream gene activation. Consistent with this finding, L-GILZ induced p21 and p53 upregulated modulator of apoptosis (PUMA) expression only in p53(+/+) cells, while L-GILZ silencing reversed the anti-proliferative activity of dexamethasone as well as expression of p53, p21 and PUMA. Furthermore, L-GILZ stabilizes p53 proteins by decreasing p53 ubiquitination and increasing MDM2 ubiquitination. These findings reveal L-GILZ as a regulator of p53 and a candidate for new therapeutic anti-cancer strategies for tumors associated with p53 deregulation.


Assuntos
Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Knockout , Estabilidade Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitinação/genética
12.
Cell Death Differ ; 21(2): 226-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24270406

RESUMO

The thymus is the primary organ responsible for de novo generation of immunocompetent T cells that have a diverse repertoire of antigen recognition. During the developmental process, 98% of thymocytes die by apoptosis. Thus apoptosis is a dominant process in the thymus and occurs through either death by neglect or negative selection or through induction by stress/aging. Caspase activation is an essential part of the general apoptosis mechanism, and data suggest that caspases may have a role in negative selection; however, it seems more probable that caspase-8 activation is involved in death by neglect, particularly in glucocorticoid-induced thymocyte apoptosis. Caspase-8 is active in double-positive (DP) thymocytes in vivo and can be activated in vitro in DP thymocytes by T-cell receptor (TCR) crosslinking to induce apoptosis. Caspase-8 is a proapoptotic member of the caspase family and is considered an initiator caspase, which is activated upon stimulation of a death receptor (e.g., Fas), recruitment of the adaptor molecule FADD, and recruitment and subsequent processing of procaspase-8. The main role of caspase-8 seems to be pro-apoptotic and, in this review, we will discuss about the involvement of caspase-8 in (1) TCR-triggered thymic apoptosis; (2) death receptor-mediated thymic apoptosis; and (3) glucocorticoid-induced thymic apoptosis. Regarding TCR triggering, caspase-8 is active in medullary, semi-mature heat-stable antigen(hi) (HAS(hi) SP) thymocytes as a consequence of strong TCR stimulation. The death receptors Fas, FADD, and FLIP are involved upstream of caspase-8 activation in apoptosis; whereas, Bid and HDAC7 are involved downstream of caspase-8. Finally, caspase-8 is involved in glucocortocoid-induced thymocyte apoptosis through an activation loop with the protein GILZ. GILZ activates caspase-8, promoting GILZ sumoylation and its protection from proteasomal degradation.


Assuntos
Caspase 8/metabolismo , Timo/enzimologia , Timo/fisiologia , Animais , Humanos
13.
Sci Total Environ ; 450-451: 13-21, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23454572

RESUMO

The present paper deals with identification of hydrocarbon sources in contaminated soil of three tank farms located in north, central and south Italy. Parent polycyclic aromatic hydrocarbons (naphthalene through benzo(g,h,i)perylene) and n-alkanes (n-C10 through n-C36) were determined. The study of source assignments was carried out by their distribution patterns, their diagnostic ratios, and determination of less-commonly used markers. The data show anthropogenic and biogenic origin of n-alkanes and petrogenic and pyrolytic sources of PAHs. Multiple sources of hydrocarbons, that were not considered in the preliminary environmental assessments, are identified. The application of a multi-criteria approach allows to locate petroleum pollution sources that affect the study sites. The results demonstrate that the application of a multi-criteria approach for source identification is a key point to assess environmental damage and prove that an accurate study of source identification has to be performed. The suggested methodology is a useful tool to manage contaminated sites and to plan appropriate interventions of clean up.


Assuntos
Alcanos/análise , Monitoramento Ambiental/métodos , Indústrias Extrativas e de Processamento , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Itália , Solo/análise , Solo/normas
14.
Rev Sci Instrum ; 84(1): 016101, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23387707

RESUMO

A wide bandwidth current probe based on a Rogowski coil was proposed to work down to the nanosecond time scale. It was then used to record the discharge current pulses that characterize the streamer regime of the plasma in a dielectric barrier discharge device. Indeed such plasmas are often made up of intermittent and highly localized structures such as streamers or microdischarges. Characteristics and performances of the probes are discussed together with a few results concerning their application to investigate dielectric barrier discharges and the temporal structure of different pulses of the electrical current.

15.
J Colloid Interface Sci ; 394: 590-7, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23266023

RESUMO

Type I collagen films have been functionalized on their surfaces by plasma treatment with carboxyl and amino groups to improve their potential for grafting bioactive molecules. The physico-chemical properties of the plasma-treated films were evaluated and compared to the untreated materials by water contact angle, SEM and AFM. The presence of new functional groups on the film surfaces has been assessed by ATR-FTIR spectra after chemical derivatization. Moreover, the biocompatibility of the plasma-treated films was studied with MG-63 human osteoblast-like cells, evaluating cell proliferation, viability and morphology at 1, 3 and 7 days.


Assuntos
Materiais Biocompatíveis/química , Colágeno Tipo I/química , Osteoblastos/citologia , Adesão Celular , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Teste de Materiais , Propriedades de Superfície , Engenharia Tecidual
16.
Reumatismo ; 64(5): 293-8, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23256104

RESUMO

OBJECTIVES: CD4+CD25high regulatory T cells (TREG) represent a suppressive T cell subset deeply involved in the modulation of immune responses and eventually in the prevention of autoimmunity. Growing evidence demonstrated that patients with autoimmune and inflammatory chronic diseases display an impairment of TREG cells or activated effector T cells unresponsive to TREG. Glucocorticoid-induced TNFR-related protein (GITR) is a widely accepted marker of murine TREG cells, but little is known in humans. Aim of the present study was to investigate the characteristics of different subsets of TREG cells in Sjögren's syndrome and the potential role of GITR as marker of human TREG cells. METHODS: Fifteen patients with primary Sjogren's syndrome (SS) and 10 sex- and age-matched normal controls (NC) were enrolled. CD4+ T cells were magnetic sorted from peripheral blood by negative selection. Cell phenotype was analyzed through flow-cytometry using primary and secondary antibodies. Disease activity was assessed using the EULAR Sjögren's syndrome disease activity index (ESSDAI). RESULTS: Although the proportion of circulating CD25highGITRhigh subset was similar in SS patients and NC, an expansion of the CD25-GITRhigh cell population was observed in the peripheral blood of SS patients. Interestingly, this expansion was more relevant in patients with inactive rather than active disease. CONCLUSIONS: The number of CD4+CD25-GITRhigh cells is increased in SS as compared to NC. Moreover, the fact that the expansion of this cell subset is prevalently observed in patients with inactive disease suggests that these cells may play a role in counteracting inflammatory response.


Assuntos
Síndrome de Sjogren/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Animais , Doenças Autoimunes/sangue , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Antígenos CD4/análise , Estudos de Casos e Controles , Modelos Animais de Doenças , Feminino , Proteína Relacionada a TNFR Induzida por Glucocorticoide/análise , Humanos , Imunofenotipagem , Subunidade alfa de Receptor de Interleucina-2/análise , Contagem de Linfócitos , Pessoa de Meia-Idade , Síndrome de Sjogren/sangue
17.
J Chemother ; 23(3): 150-7, 2011 06.
Artigo em Inglês | MEDLINE | ID: mdl-21742584

RESUMO

The leaves of Artocarpus tonkinensis are used in Vietnamese traditional medicine for treatment of arthritis, and the compound maesopsin 4-O-ß-D-glucoside (TAT-2), isolated from them, inhibits the proliferation of activated T cells. Our goal was to test the anti-proliferative activity of TAT-2 on the T-cell leukemia, Jurkat, and on the acute myeloid leukemia, OCI-AML. TAT-2 inhibited the growth of OCI-AML (and additional acute myeloid leukemia cells) but not Jurkat cells. Growth inhibition was shown to be due to inhibition of proliferation rather than increase in cell death. Analysis of cytokine release showed that TAT-2 stimulated the release of TGF-ß, yet TGF-ß neutralization did not reverse the maesopsin-dependent effect. Gene expression profiling determined that maesopsin modulated 19 identifiable genes. Transcription factor CP2 was the gene most significantly modulated. Real-time PCR validated that up-regulation of sulphiredoxin 1 homolog (SRXN1), hemeoxygenase 1 (HMOX1), and breast carcinoma amplified sequence 3 (BCAS3) were consistently modulated.


Assuntos
Benzofuranos/farmacologia , Glucosídeos/farmacologia , Heme Oxigenase-1/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Artocarpus/química , Morte Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Células HL-60 , Heme Oxigenase-1/biossíntese , Humanos , Células Jurkat , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia de Células T/tratamento farmacológico , Leucemia de Células T/genética , Leucemia de Células T/metabolismo , Leucemia de Células T/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/biossíntese , Linfócitos T/efeitos dos fármacos , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/metabolismo , Células U937 , Regulação para Cima/efeitos dos fármacos
18.
Eur J Neurol ; 18(4): 564-70, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20840352

RESUMO

BACKGROUND: Ataxia-telangiectasia (A-T) is a non-curable neurodegenerative disorder, associated with progressive neurological dysfunction, oculocutaneous telangiectasia, immunodeficiency, predisposition to cancer and radiosensitivity. A recent study documented improvement in neurological symptoms after a short-term therapy with betamethasone in patients with A-T. Aim of this study was to evaluate the minimum therapeutically effective dosage of betamethasone on neurological symptoms of A-T. METHODS: Six responsive patients with A-T, received two 20-day cycles of oral betamethasone at 0.01 and 0.03 mg/kg/day (10% and 30% of the previously used full dosage), each followed by a 20-day washout period. Clinical and laboratory evaluations were carried out at T0 and at the end of each cycle. Neurological assessment was performed through the Scale for the Assessment and Rating of Ataxia (SARA). The glucocorticoid-induced leucine zipper (GILZ) and glucocorticoid receptor (GR) RNA expression were evaluated before and during the trial through real-time PCR. RESULTS: SARA scores significantly improved in all patients at the dosage of 0.03 mg/kg/day. In particular, three patients exhibited an improvement in 5/8 variables and two patients of 7 and 8 variables, respectively. Furthermore, the clinical improvement was already evident after the lower dosage. The basal GILZ and GR RNA expression were significantly lower in patients than in controls. GILZ expression increased in all patients after the beginning of the therapy, whereas no correlation between GR and the response was found. CONCLUSION: Our data indicate that betamethasone is effective in A-T at a minimal dosage and that GILZ may be a useful biomarker of the clinical response. This study provides Class IIIA evidence that betamethasone at very low dosage is effective in improving neurological signs of patients affected with ataxia-telangiectasia.


Assuntos
Anti-Inflamatórios/administração & dosagem , Ataxia Telangiectasia/tratamento farmacológico , Betametasona/administração & dosagem , Adolescente , Biomarcadores/análise , Criança , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Receptores de Glucocorticoides/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/biossíntese , Resultado do Tratamento , Adulto Jovem
19.
Br J Pharmacol ; 162(5): 1186-201, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21091650

RESUMO

BACKGROUND AND PURPOSE: Pancreatitis represents a life-threatening inflammatory condition where leucocytes, cytokines and vascular endothelium contribute to the development of the inflammatory disease. The glucocorticoid-induced tumour necrosis factor (TNF) receptor family-related protein (GITR) is a costimulatory molecule for T lymphocytes, modulates innate and adaptive immune system and has been found to participate in a variety of immune responses and inflammatory processes. Our purpose was to verify whether inhibition of GITR triggering results in a better outcome in experimental pancreatitis. EXPERIMENTAL APPROACH: In male GITR knock-out (GITR(-/-)) and GITR(+/+) mice on Sv129 background, acute pancreatitis was induced after i.p. administration of cerulein. Other experimental groups of GITR(+/+) mice were also treated with different doses of Fc-GITR fusion protein (up to 6.25 µg·mouse⁻¹), given by implanted mini-osmotic pump. Clinical score and pro-inflammatory parameters were evaluated. KEY RESULTS: A less acute pancreatitis was found in GITR(-/-) mice than in GITR(+/+) mice, with marked differences in oedema, neutrophil infiltration, pancreatic dysfunction and injury. Co-treatment of GITR(+/+) mice with cerulein and Fc-GITR fusion protein (6.25 µg·mouse⁻¹) decreased the inflammatory response and tissue injury, compared with treatment with cerulein alone. Inhibition of GITR triggering was found to modulate activation of nuclear factor κB as well as the production of TNF-α, interleukin-1ß, inducible nitric oxide synthase, nitrotyrosine, poly-ADP-ribose, intercellular adhesion molecule-1 and P-selectin. CONCLUSIONS AND IMPLICATIONS: The GITR-GITR ligand system is crucial to the development of acute pancreatitis in mice. Our results also suggest that the Fc-GITR fusion protein could be useful in the treatment of acute pancreatitis.


Assuntos
Pancreatite/etiologia , Receptores de Fator de Crescimento Neural/fisiologia , Receptores do Fator de Necrose Tumoral/fisiologia , Animais , Apoptose , Ceruletídeo/toxicidade , Edema/etiologia , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Proteínas I-kappa B/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta/metabolismo , Ligantes , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Inibidor de NF-kappaB alfa , Infiltração de Neutrófilos , Óxido Nítrico Sintase Tipo II/metabolismo , Selectina-P/metabolismo , Pancreatite/patologia , Pancreatite/fisiopatologia , Pancreatite/prevenção & controle , Poli(ADP-Ribose) Polimerases/metabolismo , Receptores de Fator de Crescimento Neural/administração & dosagem , Receptores de Fator de Crescimento Neural/deficiência , Receptores de Fator de Crescimento Neural/genética , Receptores do Fator de Necrose Tumoral/administração & dosagem , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Linfócitos T/fisiologia , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
Cell Death Differ ; 18(1): 183-90, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20671745

RESUMO

In this study, we evaluated the possible cross-talk between glucocorticoid (GC)-induced leucine zipper (Gilz) and caspase-8 in dexamethasone (Dex)-treated thymocytes. We determined that expression of Dex-induced Gilz protein was reduced when caspase-8 activity was inhibited, and this effect was not partially due to altered Gilz mRNA expression. Inhibition of the proteasome abrogated this reduction in Gilz expression, suggesting that Dex-induced caspase-8 activation protects Gilz from degradation. We hypothesized that the caspase-8-dependent protection of Gilz could be due to caspase-8-driven sumoylation. As a putative small ubiquitin-like modifier (SUMO)-binding site was identified in the Gilz sequence, we assessed whether SUMO-1 interacted with Gilz. We identified a 30-kDa protein that was compatible with the size of a Gilz-SUMO-1 complex and was recognized by the anti-SUMO-1 and anti-Gilz antibodies. In addition, Gilz bound to SUMO ubiquitin-conjugating (E2)-conjugating enzyme Ube21 (Ubc9), the specific SUMO-1 E2-conjugating enzyme, in vitro and coimmunoprecipitated with Ubc9 in vivo. Furthermore, Gilz coimmunoprecipitated with SUMO-1 both in vitro and in vivo, and this interaction depended on caspase-8 activation. This requirement for caspase-8 was further evaluated in caspase-8-deficient thymocytes and lymphocytes in which Gilz expression was reduced. In summary, our results suggest that caspase-8 activation protects Gilz from proteasomal degradation and induces its binding to SUMO-1 in GC-treated thymocytes.


Assuntos
Caspase 8/metabolismo , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína SUMO-1/metabolismo , Glândula Tireoide/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Sítios de Ligação , Caspase 8/genética , Caspase 8/fisiologia , Células Cultivadas , Camundongos , Dados de Sequência Molecular , Ligação Proteica , Sumoilação , Glândula Tireoide/citologia , Fatores de Transcrição/química , Fatores de Transcrição/genética , Enzimas de Conjugação de Ubiquitina/metabolismo
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