RESUMO
Benign recurrent intrahepatic cholestasis (BRIC) is a rare genetic disorder that is characterized by episodes of cholestasis followed by complete resolution. The episodic nature of BRIC raises concerns about its possible trigger factors. Indeed, case reports of this orphan disease have associated BRIC to some triggers. In the absence of any reviews, we reviewed BRIC trigger factors and its pathophysiology. The study consisted of a systematic search for case reports using PubMed. Articles describing a clear case of BRIC associated with a trigger were included resulting in 22 articles that describe 35 patients. Infection was responsible for 54.3% of triggered episodes, followed by hormonal, drugs, and miscellaneous causes reporting as 30%, 10%, and 5.7% respectively. Females predominated with 62.9%. The longest episode ranged between 3 months to 2 years with a mean of 32.37 weeks. The mean age of the first episode was 14.28 ranging between 3 months to 48 years. Winter and autumn were the major seasons during which episodes happened. Hence, BRIC is potentially triggered by infection, which is most commonly a viral infection, hormonal disturbances as seen in oral contraceptive pills and pregnancy state, and less commonly by certain drugs and other causes. The appearance of cholestasis during the first two trimesters of pregnancy compared to intrahepatic cholestasis of pregnancy could help to differentiate between the two conditions. The possible mechanism of BRIC induction implicates a role of BSEP and ATP8B1. While estrogen, drugs, and cytokines are known to affect BSEP, less is known about their action on ATP8B1.
Assuntos
Colestase Intra-Hepática , Colestase , Colestase Intra-Hepática/diagnóstico , Feminino , Humanos , Lactente , GravidezRESUMO
Müllerian malformations result from defective fusion of the Müllerian ducts during development of the female reproductive system. The least common form of these malformations is Herlyn-Werner-Wunderlich syndrome characterized by obstructed hemivagina and ipsilateral renal anomaly (OHVIRA). The most common presentation of this syndrome is a mass secondary to hematocolpos, pain, and dysmenorrhea. Clinical diagnosis is very challenging and requires imaging studies in which ultrasound and MRI play an essential role in the diagnosis, classification and treatment plan. We report two cases of this syndrome, featuring two very rare clinical presentations: hematosalpinx and pyocolpos. The clinical course of the pathology is not standard and each patient is treated accordingly.
RESUMO
BACKGROUND: Leiomyomas are the most common benign tumours of the uterus. The diagnosis, evaluation and treatment of prolapsed pedunculated submucous myoma may need vaginal access compromising sometimes the hymenal integrity. Laparoscopic management of a pedunculated submucous myoma in a Middle Eastern virgin patient is described as a safe alternative. CASE: A 20-year-old, nulliparous virgin woman presented to the outpatient clinic for irregular menstrual bleeding of 2 months duration. Imaging revealed a 5×5 cm solid mass in the cervico-vaginal location filling the vagina suggestive of a prolapsed pedunculated submucous leiomyoma. Due to the patient's desire of preserving her intact hymen, a laparoscopic posterior colpotomy was performed and the mass was removed successfully. CONCLUSION: Laparoscopic posterior colpotomy, preserving the hymenal integrity in a virgin patient, provides excellent access and visualization and it is a safe tool for the management of a cervico-vaginal pedunculated submucous myoma by a skilled laparoscopic gynaecologic surgeon.
RESUMO
BACKGROUND: The occurrence of an extra-uterine leiomyoma, arising from the intra-peritoneal portion of the round ligament in a lady with Müllerian agenesis diagnosed at the age of forty is extremely rare. We report a case of this rare combination in a Middle Eastern woman. CASE: A 40 years old lady, primarily amenorrheic, presented to our clinic for an infertility consultation. The work- up showed features suggestive of Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome with a leiomyoma arising from the intra-peritoneal part of the round ligament.
RESUMO
BACKGROUND AND PURPOSE: Calcium can potentially shorten T1, generating high signal intensity in GREs. Because IPH appears as high signal intensity in MRIPH and the surface effects of calcium can potentially shorten T1 of surrounding water protons, the purpose of this study was to evaluate whether the high signal intensity seen on MRIPH could be attributed solely to IPH and not calcification. MATERIALS AND METHODS: Eleven patients undergoing carotid endarterectomy were imaged by using MRIPH. Calcification was assessed by scanning respective endarterectomy specimens with a tabletop MicroCT. MRIPH/MicroCT correlation used an 8-segment template. Two readers evaluated images from both modalities. Agreement between MRIPH/MicroCT was measured by calculating Cohen κ. RESULTS: High signal intensity was seen in 58.8% and 68.9% (readers 1 and 2, respectively) of MRIPH segments, whereas calcification was seen in 44.7% and 32.1% (readers 1 and 2, respectively) of MicroCT segments. High signal intensity seen by MRIPH showed very good but inverse agreement to calcification (κ = -0.90; P < .0001, 95% CI, -0.93 to -0.86, reader 1; and κ = -0.74; P < .0001; 95% CI, -0.81 to -0.69, reader 2). Most interesting, high signal intensity demonstrated excellent agreement with lack of calcification on MicroCT (κ = 0.92; P < .0001; 95% CI, 0.89-0.94, reader 1; and κ = 0.97; P < .0001; 95% CI, 0.96-0.99, reader 2). In a very small number of segments, high signal intensity was seen in MRIPH, and calcification was seen on MicroCT; however, these represented a very small proportion of segments with high signal intensity (5.9% and 1.6%, readers 1 and 2, respectively). CONCLUSIONS: High signal intensity, therefore, reliably identified IPH, known to describe complicated plaque, rather than calcification, which is increasingly recognized as identifying more stable vascular disease.
Assuntos
Calcinose/patologia , Doenças das Artérias Carótidas/patologia , Hemorragia Cerebral/patologia , Imagem Ecoplanar/métodos , Idoso , Idoso de 80 Anos ou mais , Calcinose/diagnóstico por imagem , Calcinose/cirurgia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Artérias Carótidas/cirurgia , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/cirurgia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/cirurgia , Imagem Ecoplanar/normas , Endarterectomia das Carótidas , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Microtomografia por Raio-XRESUMO
FT-Raman spectroscopy was employed to study normal human colorectal tissues in vitro with the aim of evaluating the spectral differences of the complex colon mucous in order to establish a characteristic Raman spectrum. The samples were collected from 39 patients, providing 144 spectra for the statistical analysis. The results enable one to establish three well-defined spectroscopic groups of non-altered colorectal tissues that were consistently checked by statistical (clustering) and biological (histopathology) analyses: group 1 is represented by samples with the presence of epithelial layer, connective tissue papillae, and smooth muscle tissue; group 2 comprises tissues with epithelial layer and connective tissue papillae; group 3 presented mostly fatty and slack conjunctive tissue. The study reveals the existence of an intrinsic spectral variability for each patient that must be considered when sampling tissues fragments to build a spectral database. This is the first step for future studies and applications of Raman spectroscopy to optical biopsy and diagnosis of colorectal cancer.
Assuntos
Biomarcadores/análise , Biomarcadores/química , Colo/química , Reto/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de ReferênciaRESUMO
Through their effects on gene activation, antioxidants have been reported to modulate cellular expression of several proinflammatory cytokines and adhesion molecules, an effect mediated by preventing translocation of the transcription factor nuclear factor-kappa B (NF-kappa B) into the nucleus. In addition, modulation of the intracellular redox state may have profound effects on cell activation and subsequent gene expression distinct from effects on NF-kappa B; these effects may account for the divergent effects of antioxidants on cytokine gene expression in various reports. In the present studies, we evaluated the effect of the antioxidant, pyrrolidine dithiocarbamate (PDTC), on murine and human myeloid cell tumor necrosis factor alpha (TNF alpha) gene and protein expression. PDTC-enhanced LPS-induced TNF alpha secretion in cells derived from a murine macrophage cell line (J774.1), as well as in primary murine peritoneal macrophages by 4-fold. The effect was both stimulus and species dependent, as TNF alpha secretion was attenuated by PDTC in human THP-1 cells and in murine cells stimulated with zymosan. Northern analysis demonstrated that these effects were evident at the level of mRNA expression. Electrophoretic mobility shift assays confirmed the down-regulatory effect of PDTC on human myeloid NF-kappa B activation, whereas in murine cells no such inhibitory effect was evident. Evaluation of TNF alpha mRNA stability in murine cells demonstrated that the potentiating effect of PDTC on TNF alpha mRNA expression was due to an increase in mRNA half-life from 37 to 93 min. Together, these data suggest that the effect of antioxidants on gene expression are both stimulus and species dependent and illustrate a novel mechanism whereby redox manipulation might modulate TNF alpha expression in vivo.
Assuntos
Antioxidantes/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Prolina/análogos & derivados , Prolina/farmacologia , RNA Mensageiro/metabolismo , Tiocarbamatos/farmacologia , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Sinergismo Farmacológico , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , Macrófagos/efeitos dos fármacos , Camundongos , Ativação TranscricionalRESUMO
This study analysed the effect of low doses of verapamil added to chronic treatment with angiotensin-converting enzyme (ACE) inhibitors on blood pressure and serum creatinine levels in eight elderly hypertensive patients who had a steady increase of serum creatinine while on ACE inhibitors. The study was performed in eight elderly hypertensive subjects, five men and three women (mean age 70+/-2 years; systolic blood pressure 173+/-4 mm Hg; diastolic blood pressure 99+/-1 mm Hg) and serum creatinine of 1.60+/-0.27 mg/dl before treatment. During an average of 25 weeks, ACE inhibitors significantly reduced both systolic and diastolic blood pressures, but serum creatinine levels were increased over basal levels (0,68+/-0,20 mg/dl, p < 0.05). During an average of 10 weeks, the addition of verapamil did not decrease blood pressure further, but serum creatinine levels were reduced to baseline. Our study suggests that the addition of verapamil to ACE inhibitors can reverse ACE-induced increase in creatinine levels in elderly hypertensive patients in whom this side effect is observed.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão/tratamento farmacológico , Verapamil/uso terapêutico , Adolescente , Adulto , Fatores Etários , Idoso , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
IL-1 beta-converting enzyme (ICE), also known as caspase-1, subserves two dichotomous biologic roles. It processes newly synthesized pro-IL-1 beta to yield the active cytokine and, as the human homologue of the Caenorhabditis elegans gene product, ced-3, it also induces cellular apoptosis through the cleavage of key intracellular structural and regulatory proteins and through the catalytic activation of other caspase family members. We show here that two different proinflammatory stimuli, LPS and granulocyte-macrophage-CSF, up-regulate the expression of both ICE and IL-1 beta in human polymorphonuclear neutrophils, and that the ICE-dependent cleavage of pro-IL-1 beta results in delayed expression of the constitutive cell death program. The apoptotic delay can be blocked by inhibiting tyrosine kinases or NF-kappa B activation and by inhibiting protein synthesis. Since an antisense oligonucleotide for IL-1 beta, a blocking Ab to IL-1 beta, and preincubation with the IL-1R antagonist all prevent the delay in apoptosis, we conclude that IL-1 beta acts in an autocrine manner to inhibit granulocyte programmed cell death. We conclude that caspase-1 (ICE) subserves both pro- and antiapoptotic roles; the latter role is evident during inflammation as an inhibition of spontaneous neutrophil apoptosis through the processing of IL-1 beta. The ICE-dependent activation of IL-1 beta may represent a common autocrine pathway for the divergent stimuli that inhibit the constitutive expression of neutrophil programmed cell death during inflammation.
Assuntos
Apoptose/imunologia , Cisteína Endopeptidases/fisiologia , Interleucina-1/metabolismo , Ativação de Neutrófilo , Neutrófilos/enzimologia , Neutrófilos/imunologia , Apoptose/efeitos dos fármacos , Proteínas Sanguíneas/biossíntese , Caspase 1 , Cisteína Endopeptidases/biossíntese , Cisteína Endopeptidases/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Inflamação/enzimologia , Inflamação/imunologia , Lipopolissacarídeos/farmacologia , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/patologia , Precursores de Proteínas/biossíntese , Precursores de Proteínas/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosAssuntos
Artrite Infecciosa/complicações , Infecção por Mycobacterium avium-intracellulare/complicações , Osteomielite/complicações , Pneumonia Bacteriana/complicações , Artrite Infecciosa/microbiologia , Feminino , Humanos , Pessoa de Meia-Idade , Infecção por Mycobacterium avium-intracellulare/microbiologia , Osteomielite/microbiologia , Pneumonia Bacteriana/microbiologia , Articulação Esternoclavicular/microbiologiaRESUMO
The intracellular redox state regulates several aspects of cell function, suggesting that strategies directed toward altering the cellular redox state may modulate cell activation in inflammatory states. As the most abundant intracellular thiol, glutathione plays a critical role as an intracellular redox buffer. Using diethylmaleate (DEM) as a glutathione-depleting agent, we evaluated the effects of GSH depletion in a rodent model of polymorphonuclear neutrophil (PMN)-dependent acute lung injury. Rats received 500 microg of LPS by intratracheal challenge, inducing a 5.5-fold increase in lung permeability and sixfold increase in lung PMN content. Pretreatment with DEM prevented the LPS-induced increase in lung PMN influx and lung permeability. Northern analysis and immunohistochemical studies suggest that this effect may be mediated by preventing up-regulation of lung ICAM-1 mRNA and protein expression. This effect is specific to ICAM-1, because lung cytokine-induced neutrophil chemoattractant and TNF-alpha mRNA levels are unaffected. This finding is not unique to the lung, because a similar effect on PMN influx was recapitulated in a rodent model of chemical peritonitis. Further, in vitro studies demonstrated that pretreatment of HUVEC monolayers with DEM prevented both ICAM-1 up-regulation and PMN transendothelial migration. These data indicate the presence of a thiol-sensitive mechanism for modulating ICAM-1 gene expression and suggest a potential novel therapeutic strategy for diseases characterized by PMN-mediated tissue injury.
Assuntos
Regulação da Expressão Gênica , Molécula 1 de Adesão Intercelular/genética , Lipopolissacarídeos/toxicidade , Síndrome do Desconforto Respiratório/metabolismo , Compostos de Sulfidrila/fisiologia , Animais , Glutationa/fisiologia , Humanos , Molécula 1 de Adesão Intercelular/análise , Masculino , Maleatos/farmacologia , Camundongos , Neutrófilos/fisiologia , Oxirredução , RNA Mensageiro/análise , Coelhos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genéticaRESUMO
Lung injury in the acute respiratory distress syndrome (ARDS) is in part due to polymorphonuclear leukocyte (PMN)-mediated oxidative tissue damage. By means of nuclear factor-kappaB (NF-kappaB) activation, oxidants may also induce several genes implicated in the inflammatory response. The dithiocarbamates are antioxidants with potent inhibitory effects on NF-kappaB. We postulated that the pyrrolidine derivative pyrrolidine dithiocarbamate (PDTC) would attenuate lung injury following intratracheal challenge with endotoxin (lipopolysaccharide; LPS) through its effect as an antioxidant and inhibitor of gene activation. Rats were given PDTC (1 mmole/kg) by intraperitoneal injection, followed by intratracheal administration of LPS. The transpulmonary flux of [125I] albumin (permeability index; PI) was used as a measure of lung injury. Northern blot analysis of total lung RNA was performed to assess induction of tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecule-1 (ICAM-1) messenger RNA (mRNA) as markers of NF-kappaB activation. The effect of in vivo treatment with PDTC on LPS-induced NF-kappaB DNA binding activity in macrophage nuclear extracts was evaluated with the electrophoretic mobility shift assay (EMSA). PDTC administration attenuated LPS-induced increases in lung permeability (PI = 0.16 +/- 0.02 for LPS versus 0.06 +/- 0.01 for LPS + PDTC; P < 0.05). TNF-alpha levels and PMN counts in bronchoalveolar lavage fluid (BALF) were unaffected, as were whole-lung TNF-alpha and ICAM-1 mRNA expression. PDTC had no effect on NF-kappaB activation as evaluated with EMSA. PDTC reduced lung lipid peroxidation as assessed by levels of malondialdehyde, without reducing neutrophil oxidant production. We conclude that PDTC attenuates LPS-induced acute lung injury. This effect occurs independently of any effect on NF-kappaB. PDTC reduces oxidant-mediated cellular injury, as demonstrated by a reduction in the accumulation of malondialdehyde. Administration of PDTC may represent a novel approach to limiting neutrophil-mediated oxidant injury.
Assuntos
Antioxidantes/farmacologia , Endotoxinas/toxicidade , Pulmão/patologia , Pirrolidinas/farmacologia , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Tiocarbamatos/farmacologia , Animais , Antioxidantes/uso terapêutico , Humanos , Recém-Nascido , Molécula 1 de Adesão Intercelular/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , NF-kappa B/metabolismo , Pirrolidinas/uso terapêutico , Ratos , Síndrome do Desconforto Respiratório do Recém-Nascido/patologia , Tiocarbamatos/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: We have previously shown that the thiol-oxidizing agent diethyl maleate prevents lipopolysaccharide (LPS)-induced up-regulation of endothelial cell intercellular adhesion molecule-1 (ICAM-1) in vitro. OBJECTIVE: To determine the effect of glutathione depletion on the development of local skin inflammation in vivo, a model known to be dependent on ICAM-1. DESIGN: Swiss Webster mice were injected with intradermal LPS (30 micrograms) or isotonic saline solution. INTERVENTION: Mice were pretreated for 1 hour with intraperitoneal diethyl maleate (6 mmol/kg) or corn oil vehicle. MAIN OUTCOME MEASURES: Injection sites were harvested after 12 and 24 hours and evaluated for changes in vascular permeability and histological characteristics. To determine the mechanism underlying our findings, we evaluated skin ICAM-1 immunohistochemistry, levels of ICAM-1 protein and messenger RNA (mRNA), and neutrophil CD11b expression at the 24-hour point. RESULTS: Diethyl maleate significantly decreased the skin permeability index in a dose-dependent fashion at 24 hours but not at 12 hours. Skin histological examination under light microscopy showed a marked LPS-induced neutrophil infiltration at 24 hours, which was inhibited with diethyl maleate pretreatment. Immunohistochemical examination showed that diethyl maleate reduced ICAM-1 expression. In keeping with the hypothesized mechanism, diethyl maleate attenuated the LPS-induced up-regulation of ICAM-1 mRNA by 44%. Diethyl maleate also slightly but insignificantly reduced CD11b expression in vivo. CONCLUSIONS: Diethyl maleate markedly attenuates LPS-induced dermal inflammation, primarily through a reduction in ICAM-1 protein and mRNA expression. These data suggest that manipulation of the intracellular redox state may have a beneficial role in neutrophil-mediated inflammation.
Assuntos
Dermatite/imunologia , Escherichia coli , Glutationa/antagonistas & inibidores , Lipopolissacarídeos/imunologia , Animais , Antígenos CD11/biossíntese , Dermatite/patologia , Dermatite/prevenção & controle , Molécula 1 de Adesão Intercelular/biossíntese , Maleatos/farmacologia , CamundongosRESUMO
BACKGROUND: Fas and tumor necrosis factor receptor 1 (TNFR1) are membrane proteins that signal for apoptotic cell death by downstream activation of proteins of the interleukin-1 beta converting enzyme (ICE) family. Spontaneous apoptosis is delayed in neutrophils activated by transmigration into an inflammatory focus. In this study we evaluated the effects of transmigration on Fas and TNFR1-induced apoptosis and apoptotic gene expression. METHODS: Sprague-Dawley rats were killed 4 hours after intratracheal challenge with 500 micrograms lipopolysaccharide (LPS). Neutrophils isolated from the systemic circulation (circulation) or bronchoalveolar lavage fluid (lung) were incubated with or without an agonistic antibody to Fas (clone CH-11, 100 ng/ml) or TNF (10 ng/ml) for 24 hours. Apoptosis and Fas expression were assessed by flow cytometry. Expression of the antiapoptotic protein Bcl-2 and proapoptotic proteins ICE and CPP32 were measured by Western blots. RESULTS: Neutrophils transmigrating into the lung in response to LPS showed delayed apoptosis compared with circulating neutrophils and failed to undergo apoptosis in response to anti-Fas antibody or TNF-alpha. Fas expression was unaltered; however, TNFR1 expression was reduced. Bcl-2 was not detected in either group; both the pro- and active forms of ICE and active CPP32 were significantly decreased in lung neutrophils. The specific ICE inhibitor, YVAD-CMK, partially blocked the increased rates of apoptosis resulting from engagement of Fas or TNFR1. CONCLUSIONS: Neutrophil transmigration retards apoptosis through engagement of the death receptors Fas and TNFR1. This refractory state is associated with reduced levels of proapoptotic proteins. Blunted responsiveness to physiologic apoptotic stimuli prolongs neutrophil functional survival during acute inflammation and may contribute to the tissue injury associated with acute respiratory distress syndrome.
Assuntos
Apoptose , Cisteína Endopeptidases/metabolismo , Pulmão/fisiopatologia , Neutrófilos/patologia , Neutrófilos/fisiologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Anticorpos , Antígenos CD/biossíntese , Apoptose/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/citologia , Caspase 1 , Núcleo Celular/metabolismo , Quimiotaxia de Leucócito/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Escherichia coli , Inflamação , Cinética , Lipopolissacarídeos/toxicidade , Masculino , Neutrófilos/citologia , Ratos , Ratos Sprague-Dawley , Receptores do Fator de Necrose Tumoral/biossíntese , Receptores Tipo I de Fatores de Necrose Tumoral , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Receptor fas/biossíntese , Receptor fas/imunologia , Receptor fas/fisiologiaRESUMO
HL-60 cells differentiating into neutrophil-like cells die an apoptotic death in vitro. Susceptibility to apoptosis is associated with decreased Bcl-2 protein and mRNA expression; however, the effect of differentiation on the expression of pro-apoptotic caspases is unknown. Spontaneous apoptosis occurred 6 days after retinoic acid treatment. Western blotting showed loss of Bcl-2 by day 7, and new expression of ICE (caspase 1) and CPP32 (caspase 3) protein by day 2. Northern analysis demonstrated loss of Bcl-2 mRNA and increases in ICE mRNA by day 2; CPP32 mRNA was unchanged. Differential Bcl-2 and ICE mRNA expression was also found when granulocytic differentiation was stimulated by DMSO. Differentiated HL-60 cell lysates exhibited functional ICE proteolytic activity. De novo caspase expression was responsible for the development of spontaneous apoptosis, since specific inhibitors of ICE (YVAD-CMK) and CPP32 (DEVD-CHO), inhibited retinoic acid induced spontaneous apoptosis. Functional maturation and susceptibility to apoptosis are both inducible and linked in this granulocyte precursor cell line.
Assuntos
Apoptose , Cisteína Endopeptidases/biossíntese , Granulócitos/citologia , Granulócitos/enzimologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Caspase 1 , Diferenciação Celular/efeitos dos fármacos , Cisteína Endopeptidases/efeitos dos fármacos , Cisteína Endopeptidases/fisiologia , Inibidores de Cisteína Proteinase/farmacologia , Granulócitos/efeitos dos fármacos , Células HL-60 , Humanos , Neutrófilos/enzimologia , Neutrófilos/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , RNA Mensageiro/biossíntese , Transdução de Sinais , Tretinoína/farmacologia , Receptor fas/fisiologiaRESUMO
gamma delta T-cells have been implicated in the immunopathogenesis of multiple sclerosis (MS), possibly through interaction with heat shock proteins (hsp). We have previously demonstrated that human oligodendrocytes (OGC) express hsp on their surface and induce the proliferation and expansion of gamma delta T-cells. We also showed that gamma delta T-cells are highly cytolytic to OGC in vitro. The current study addresses whether gamma delta T-cell-induced cytotoxicity to OGC involves the recognition of hsp on OGC or some other ligand. We first compared the lytic potential for different human glial cells and found that gamma delta T-cells lysed OGC, microglia and human fetal astrocytes to the same extent, despite the preferential expression of hsp only on OGC. This suggested that either hsp was not involved in cytolytic recognition or that more than one ligand exists. To address this we used cell lines that either shared OGC properties of hsp expression and the ability to stimulate gamma delta T-cells (RPMI 8226, Daudi) or did not (U937) in cold target competition assays with OGC. Results demonstrated that although all the cell lines were effectively killed by gamma delta T-cells, only the RPMI 8226 and Daudi cells were able to effectively compete for lysis with the OGC. These results support the notion that probably more than one ligand for gamma delta T-cell cytotoxic recognition exists but hsp could still be involved in gamma delta T-cell-induced lysis of OGC. Regulating the expression of hsp on OGC might therefore be a way of interfering with potential gamma delta T-cell-induced damage in MS.
Assuntos
Comunicação Celular , Proteínas de Choque Térmico/metabolismo , Neuroglia/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T Citotóxicos/fisiologia , Linfócitos T/fisiologia , Astrócitos/fisiologia , Linhagem Celular , Feto/citologia , Humanos , Microglia/fisiologia , Oligodendroglia/metabolismo , Oligodendroglia/fisiologia , Acetato de Tetradecanoilforbol/farmacologiaRESUMO
Adhesion molecules such as VLA-4 are important not only for monocyte adhesion to extracellular matrix proteins, but also for subsequent cell activation. Monocyte adherence to fibronectin or engagement of VLA-4 has been demonstrated to stimulate production of potent inflammatory mediators such as tumor necrosis factor-alpha, interleukin-1, and the procoagulant tissue factor protein. However, the intracellular signaling cascades leading to gene expression have not been elucidated. Using the human monocytic THP-1 cell line, VLA-4 cross-linking by monoclonal antibodies directed against its alpha4 and beta1 subunits produced a time-dependent increase in tyrosine phosphorylation of a broad range of cellular proteins. Using Western blot analysis directed against the phosphorylated form of the extracellular signal-related kinase (ERK) mitogen-activated protein (MAP) kinase proteins, as well as immunoprecipitation and in vitro kinase assays, we found that VLA-4 cross-linking increased ERK1/ERK2 tyrosine phosphorylation and activity. In conjunction, integrin cross-linking also increased NF-kappaB nuclear translocation and 4-h expression of tissue factor. Inhibition of tyrosine kinase activity with genistein (10 microg/ml) as well as selective MAP kinase inhibition with the MEK-1 inhibitor PD98059 abolished the VLA-4-dependent ERK tyrosine phosphorylation, inhibited NF kappaB nuclear binding, and abrogated tissue factor expression induced by both VLA-4 cross-linking and adhesion to fibronectin in THP-1 cells and human peripheral blood monocytes. These studies point to the involvement of the MAP kinase pathway in the activation of monocytic cells during transmigration to inflammatory sites.
Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Integrina beta1/metabolismo , Integrinas/metabolismo , Proteínas Nucleares/metabolismo , Receptores de Retorno de Linfócitos/metabolismo , Receptores de Antígeno muito Tardio/metabolismo , Tromboplastina/biossíntese , Transativadores/metabolismo , Proteínas Virais , Dedos de Zinco , Inibidores Enzimáticos/farmacologia , Fibronectinas/metabolismo , Flavonoides/farmacologia , Genisteína , Humanos , Integrina alfa4beta1 , Isoflavonas/farmacologia , NF-kappa B/metabolismo , Fosforilação , Tirosina/metabolismoAssuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão/tratamento farmacológico , Verapamil/uso terapêutico , Idoso , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Bloqueadores dos Canais de Cálcio/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Hipertensão/complicações , Falência Renal Crônica/induzido quimicamente , Falência Renal Crônica/etiologia , Masculino , Verapamil/efeitos adversosRESUMO
Nuclear factor (NF)-kappa B proteins regulate the transcription of numerous genes involved in the immune response, transcription control, and viral pathogenesis. To examine the effect of ectopic expression of NF-kappa B proteins on DNA-binding activity and gene expression, individual NF-kappa B subunit genes were introduced into NIH 3T3 cells via retrovirus-mediated gene transfer. Expression of NF-kappa B subunits RelA (p65), NF-kappa B1 (p105), NF-kappa B2 (p100), and c-Rel increased the basal level of nuclear NF-kappa B DNA binding in NIH 3T3 cells, whereas expression of delta RelA (p65 delta) and NF-kappa B2 (p52) subunits did not affect basal level activity. Tumor necrosis factor-alpha treatment of the NF-kappa B-expressing cells stimulated the induced level of DNA-binding activity, reflecting interaction between endogenous murine and transfected human NF-kappa B proteins. Interestingly, expression of RelA (p65), c-Rel, NF-kappa B1 (p105), NF-kappa B2 (p100), and NF-kappa B2 (p52) subunits increased I kappa B alpha protein levels from 3- to 30-fold, indicating that one mechanism to compensate for the increased expression of NF-kappa B proto-oncogenes was to increase the synthesis and/or stability of the regulatory I kappa B alpha protein. In addition, overexpression of RelA (p65), c-Rel, NF-kappa B2 (p100), and NF-kappa B2 (p52) altered the induction kinetics of IFN-beta mRNA after Sendai virus infection, whereas overexpression of NF-kappa B1 (p105) dramatically decreased IFN-beta mRNA induction.