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1.
Infect Immun ; 82(11): 4508-17, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25114117

RESUMEN

Previous studies have indicated that group B streptococcus (GBS), a frequent human pathogen, potently induces the release of interleukin-1ß (IL-1ß), an important mediator of inflammatory responses. Since little is known about the role of this cytokine in GBS disease, we analyzed the outcome of infection in IL-1ß-deficient mice. These animals were markedly sensitive to GBS infection, with most of them dying under challenge conditions that caused no deaths in wild-type control mice. Lethality was due to the inability of the IL-1ß-deficient mice to control local GBS replication and dissemination to target organs, such as the brain and the kidneys. Moreover, in a model of inflammation induced by the intraperitoneal injection of killed GBS, a lack of IL-1ß was associated with selective impairment in the production of the neutrophil chemokines CXCL1 and CXCL2 and in neutrophil recruitment to the peritoneal cavity. Decreased blood neutrophil counts and impaired neutrophil recruitment to the brain and kidneys were also observed during GBS infection in IL-1ß-deficient mice concomitantly with a reduction in CXCL1 and CXCL2 tissue levels. Notably, the hypersusceptibility to GBS infection observed in the immune-deficient animals was recapitulated by neutrophil depletion with anti-Gr1 antibodies. Collectively, our data identify a cytokine circuit that involves IL-1ß-induced production of CXCL1 and CXCL2 and leads the recruitment of neutrophils to GBS infection sites. Moreover, our data point to an essential role of these cells in controlling the progression and outcome of GBS disease.


Asunto(s)
Quimiocina CXCL1/metabolismo , Quimiocina CXCL2/metabolismo , Interleucina-1beta/metabolismo , Neutrófilos/fisiología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/inmunología , Animales , Quimiocina CXCL1/genética , Quimiocina CXCL2/genética , Femenino , Humanos , Interleucina-1beta/genética , Ratones , Ratones Noqueados , Peritonitis/inmunología , Peritonitis/microbiología , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Infecciones Estreptocócicas/inmunología
2.
Pigment Cell Melanoma Res ; 26(2): 193-204, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23176534

RESUMEN

Here, we explored the effects of the novel class II-specific histone deacetylase inhibitors (HDACis) MC1568 and MC1575 on interleukin-8 (IL-8) expression and cell proliferation in cutaneous melanoma cell line GR-M and uveal melanoma cell line OCM-3 upon stimulation with phorbol 12-myristate 13-acetate (PMA). We found that PMA upregulated IL-8 transcription via the AP-1 binding site and identified c-Jun as the transcription factor involved in this eventS. MC1568 and MC1575 inhibited IL-8 levels and cell proliferation in either unstimulated or PMA-stimulated melanoma cells. They acted by suppressing (i) c-Jun binding to the IL-8 promoter, (ii) recruitment of histones 3 and 4, RNA polymerase II and TFIIB to the c-Jun promoter, and (iii) c-Jun expression. Our findings provide new insights into mechanisms underlying anti-tumoral activities of class II-specific HDACis in human melanoma and suggest that they may constitute a novel therapeutic strategy for improving the treatment of this cancer.


Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Ácidos Hidroxámicos/farmacología , Interleucina-8/genética , Melanoma/genética , Pirroles/farmacología , Neoplasias Cutáneas/genética , Acetilación/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ARN Polimerasas Dirigidas por ADN/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Histona Desacetilasas/genética , Histonas/metabolismo , Humanos , Interleucina-8/metabolismo , Melanoma/enzimología , Melanoma/patología , Regiones Promotoras Genéticas , Unión Proteica/efectos de los fármacos , Unión Proteica/genética , Proteínas Proto-Oncogénicas c-jun/genética , Proteínas Proto-Oncogénicas c-jun/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol/farmacología , Factor de Transcripción AP-1/metabolismo , Factor de Transcripción TFIIB/metabolismo , Transcripción Genética/efectos de los fármacos , Neoplasias de la Úvea/enzimología , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/patología
3.
Minerva Chir ; 67(6): 499-504, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23334113

RESUMEN

AIM: Pelvic pain affects 4% to 39% of women and accounts for 10-40% of all outpatient gynecologic visits. The etiology of painful endometriosis-related has not been fully delineated. No studies have been published concerning gluten-free diet administered to achieved relief of painful symptoms endometriosis-related. The aim of this retrospective study was to evaluate the effectiveness for the outcomes of endometriosis-related pain and quality of life of gluten-free diet in a follow-up of 12 months in patients with chronic pelvic pain endometriosis-related. METHODS: Two hundred seven patients with severe painful endometriosis-related symptoms entered the study. At enrolment time, the baseline values of painful symptoms were assessed by Visual Analogue Scale (VAS) for dysmenorrhoea, non-menstrual pelvic pain, and dyspareunia. According to VAS, pain severity was scored from 0-10; 0 indicating the absence of pain, and 1-4, 5-7 and 8-10 mild, moderate and severe respectively. A gluten-free diet was submitted to all patients and a new evaluation was performed after 12 months of diet. Student t test was used for statistical analysis. RESULTS: At 12 month follow-up, 156 patients (75%) reported statistically significant change in painful symptoms (P<0.005), 51 patients (25%) reported not improvement of symptoms. No patients reported worsening of pain. A considerable increase of scores for all domains of physical functioning, general health perception, vitality, social functioning, and mental health was observed in all patients (P<0.005). CONCLUSION: In our experience, painful symptoms of endometriosis decrease after 12 months of gluten free diet.


Asunto(s)
Dieta Sin Gluten , Endometriosis/complicaciones , Dolor Pélvico/dietoterapia , Dolor Pélvico/etiología , Adolescente , Adulto , Femenino , Humanos , Estudios Retrospectivos , Adulto Joven
4.
Br J Dermatol ; 162(5): 1093-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19845668

RESUMEN

BACKGROUND: Several cancer-related genes are silenced by promoter hypermethylation in skin cancers. However, to date the somatic epigenetic events that occur in cutaneous squamous cell carcinoma (SCC) tumorigenesis have not been well defined. OBJECTIVES: To examine epigenetic abnormalities of FOXE1, a gene located on chromosome 9q22, a region frequently lost in SCC. METHODS: We investigated the methylation status of FOXE1 in 60 cases of cutaneous SCC by methylation-specific polymerase chain reaction, and comparatively examined mRNA and protein expression by real-time polymerase chain reaction and Western blot, respectively. RESULTS: We found a higher frequency of FOXE1 promoter hypermethylation in SCCs (55%), as compared with the adjacent uninvolved skin (12%) and blood control samples (9.5%). FOXE1 methylation was frequently seen in association with a complete absence of or downregulated gene expression. Treatment with the demethylating agent 5-Aza-2'-deoxycytidine resulted in profound reactivation of FOXE1 expression. CONCLUSIONS: These results indicate that FOXE1 is a crucial player in development of cutaneous SCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Metilación de ADN , Factores de Transcripción Forkhead/genética , Neoplasias Cutáneas/genética , Anciano , Antimetabolitos Antineoplásicos/uso terapéutico , Azacitidina/análogos & derivados , Azacitidina/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/metabolismo , ADN de Neoplasias/genética , Decitabina , Femenino , Factores de Transcripción Forkhead/biosíntesis , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/biosíntesis , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , ARN Neoplásico/genética , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/metabolismo
5.
Br J Dermatol ; 162(3): 681-3, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19930442

RESUMEN

BACKGROUND: FOXE1 is a candidate tumour suppressor gene at human chromosome locus 9q22. This is a region frequently lost in squamous cell cancer. OBJECTIVES: To assess the influence of FOXE1 variations on genetic susceptibility to cutaneous squamous cell carcinoma (SCC). METHODS: We performed mutational analysis of FOXE1 in 320 DNA samples isolated from 60 SCC specimens, 60 adjacent histologically normal skin samples and 200 blood samples. RESULTS: No somatic mutations were evident. Instead the polyalanine tract showed marked variation in its length between samples from patients with SCC and normal controls. CONCLUSIONS: These results imply that another tumour suppressor gene at this locus may be more important than FOXE1 in skin carcinogenesis and suggest that variation in the FOXE1 polyalanine tract length predisposes to cutaneous SCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Factores de Transcripción Forkhead/genética , Genes Supresores de Tumor , Neoplasias Cutáneas/genética , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Análisis Mutacional de ADN , Femenino , Humanos , Masculino , Mutación
7.
Transplant Proc ; 37(10): 4563-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16387171

RESUMEN

The success of recovery after liver resection depends on the regeneration and functions of the remnant liver. In this study we investigated whether liver regeneration was facilitated by nandrolone decaonate after two-thirds partial hepatectomy in rats. Study animals were pretreated with nandrolone (5 mg/kg), while control animals received a placebo. Animal were sacrificed at 12, 24, 48, and 72 hours. We compared the survival rates, liver function tests as well as the amount of apoptosis by terminal deoxynucleotidyl transferase-mediated deoxyuridine-biotin nick end labeling assay, and regeneration, which was expressed as ratio of proliferating cell nuclear antigen and restoration ratio. A significant increase in hepatocyte regeneration at 24 and 48 hours in partially hepatectomized rats treated with nandrolone decaonate was observed compared to controls. This observation was confirmed by the significant acceleration of the liver restoration rate, which was 1/5 faster than in partially hepatectomized controls. The results of this study indicate that liver regeneration in rats treated with nandrolone show a prompt, faster regeneration after partial hepatectomy.


Asunto(s)
Anabolizantes/farmacología , Regeneración Hepática/fisiología , Hígado/citología , Nandrolona/farmacología , Animales , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Regeneración Hepática/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas Lew , Vacuolas/efectos de los fármacos , Vacuolas/ultraestructura
9.
J Periodontol ; 75(6): 877-85, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15295956

RESUMEN

BACKGROUND: Polyamines spermine, spermidine, and putrescine are involved in a number of inflammatory diseases, but their role in the development of gingivitis and periodontitis has not been fully investigated. The goal of this investigation was to study the levels and the variations of these amines, and the main enzymes related to their metabolism, during archwire orthodontic treatment, a condition which may induce gingivitis. METHODS: Sixty patients (age range: 11 to 27 years) were examined for gingivitis occurring during nickel-titanium (Ni-Ti) archwire orthodontic treatment. Plaque and gingival indexes (PI, GI) as well as salivary polyamine metabolism before the archwire insertion (T0) and at 3 (T1), 6 (T2), and 12 (T3) months of treatment were measured. RESULTS: In patients in the age range of 14 to 17 years, spermine and spermidine, but not putrescine contents, as well as ornithine-decarboxylase (ODC) and S-adenosylmethionine-decarboxylase (SAMDC) activities, significantly rose at 3 months after insertion, without any change in periodontal parameters, and further increased at 6 months reaching the maximum at 12 months. GI increased later, from 6 to 12 months, while PI did not significantly change. Spermidine/spermine-N1-acetyltransferase (SSAT) activity remained unchanged from T0 to T3. On the contrary, in patients whose age was 11 to 13 or over 18 years, no significant variations in polyamine metabolism and periododontal parameters were observed at any examination time. CONCLUSION: These data support the hypothesis that salivary polyamines might be earlier indicators of gingivitis than the gingival index score in adolescents wearing archwire appliances.


Asunto(s)
Aleaciones Dentales/efectos adversos , Gingivitis/etiología , Níquel/efectos adversos , Alambres para Ortodoncia/efectos adversos , Poliaminas/metabolismo , Titanio/efectos adversos , Acetiltransferasas/metabolismo , Adenosilmetionina Descarboxilasa/metabolismo , Adolescente , Adulto , Factores de Edad , Análisis de Varianza , Niño , Femenino , Humanos , Masculino , Ornitina Descarboxilasa/metabolismo , Índice Periodontal , Saliva/química , Saliva/enzimología , Estadísticas no Paramétricas
10.
Transplant Proc ; 36(2): 283-5, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15050134

RESUMEN

Ischemic preconditioning (IP), obtained by exposure to brief periods of vascular occlusion, improves organ tolerance to prolonged ischemia. The aim of this study was to evaluate the effects of IP on intestinal morphology. Forty rats were subjected to sham surgery (n = 20, group I) or intestinal preconditioning (n = 20, group II) with a cycle of brief ischemia/reperfusion (10-minute occlusion of superior mesenteric artery [SMA], followed by 10-minute reperfusion) before prolonged ischemia produced by SMA occlusion (45 minutes). Five animals in each group were sacrificed 2, 12, 24, and 48 hours after reperfusion. Intestinal samples were processed for light and electron microscopy. A TUNEL assay was performed to detect apoptosis. Statistical analysis used Student t test and Kaplan-Meier survival curves. The overall mortality for the sham-operated group was 15%, while no animals of group II died (NS). Histological evaluation showed early detachment of epithelial cells from villous stroma accompanied by marked congestion and edema. Successive morphological changes were represented by leukocyte infiltration, focal necrosis, and marked villus denudation or loss. Group II animals showed significantly reduced inflammatory infiltrates in the lamina propria and a greater villus height compared to group I. The maximum number of apoptotic nuclei was observed in both groups, Following 2 hours of reperfusion group II animals showed significantly, greater apoptosis at 2 and 12 hours after reperfusion (P <.05). Electron microscopy showed severe mitochondrial and basement membrane damage. The findings from this study confirm that IP preconditioning attenuates morphological alterations that are invariably present after prolonged ischemia and reperfusion.


Asunto(s)
Íleon/irrigación sanguínea , Precondicionamiento Isquémico/métodos , Daño por Reperfusión/prevención & control , Animales , Membrana Basal/patología , Membrana Basal/ultraestructura , Íleon/patología , Íleon/ultraestructura , Masculino , Mitocondrias/patología , Mitocondrias/ultraestructura , Ratas , Ratas Endogámicas ACI
11.
Transplant Proc ; 36(10): 2944-6, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15686666

RESUMEN

Melatonin, the primary pineal hormone, has been reported to protect from oxidative injury after ischemia-reperfusion (IR). The aim of this study was to evaluate the effects of exogenous melatonin on intestinal integrity, ileal colonization, and bacterial translocation 45-minute after mesenteric IR. Sixteen male ACI rats randomly divided into two groups underwent 45-minutes intestinal ischemia by clamping the superior mesenteric artery. One hour prior to ischemia, study animals (n=8, group A) were treated with melatonin (10 mg/kg IP) while control animals (n=8, group B) received the same volume of saline solution. An additional six animals underwent laparotomy and served as a sham-operated group. Animals were sacrificed 24 hours after reperfusion; peritoneal swabs and biopsies of liver, spleen, lung, mesenteric lymph nodes, cecum, and terminal ileum were obtained for microbiology. The ileum samples were also processed for histopathological evaluation of IR-induced injury. Twenty-four hours after reperfusion bacterial translocation to the peritoneal cavity present in all group B animals was reduced to 37.5% among those that were melatonin-treated (group A; P <.05). Furthermore bacterial translocation to mesenteric lymph nodes, spleen, and liver was significantly lower in group A than group B (P <.05). Although cecal and ileal counts did not differ between the two groups, ileal counts from control animals showed increased colonization. Accordingly, a single injection of exogenous melatonin significantly reduced the intestinal IR injury and prevented bacterial translocation.


Asunto(s)
Traslocación Bacteriana/efectos de los fármacos , Intestinos/irrigación sanguínea , Melatonina/farmacología , Daño por Reperfusión/prevención & control , Animales , Modelos Animales de Enfermedad , Hígado/microbiología , Pulmón/microbiología , Ganglios Linfáticos/microbiología , Masculino , Peritoneo/microbiología , Ratas , Ratas Endogámicas ACI , Bazo/microbiología
12.
Amino Acids ; 22(2): 119-30, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12395180

RESUMEN

Until now information about the influence of puberty on gingival tissue responses to Ni-Ti alloy haven't been available. Since our previous researches have demonstrated that Ni-Ti appliances have an influence on hyperplastic gingivopathy and data has pointed out a possible hormonal influence on the susceptibility of gingival tissue to mechanical stress, we have attempted to study the relationship between fertility hormones and the periodontal response to Ni-Ti appliances. Three groups, ranging from 6 to 17 years old, were tested for salivary polyamine concentrations and for fertility hormone levels 12 months after Ni-Ti application. Results obtained from Pearson's correlation coefficient between polyamine and sexual hormone concentrations, as well as gingival and plaque indexes, suggest that the adolescent gingival tissue undergoes an hyperplastic process after long-term use of Ni-Ti appliances in relation to the puberty age-restricted peak of fertility hormones.


Asunto(s)
Níquel/farmacología , Alambres para Ortodoncia , Poliaminas/metabolismo , Saliva/efectos de los fármacos , Titanio/farmacología , Adolescente , Factores de Edad , Niño , Cromatografía Líquida de Alta Presión , Femenino , Gingivitis , Humanos , Masculino , Aparatos Ortodóncicos , Poliaminas/análisis , Pubertad , Saliva/metabolismo
13.
J Chromatogr B Biomed Sci Appl ; 757(1): 111-7, 2001 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-11419735

RESUMEN

A high-performance liquid chromatographic method for the determination of polyamines (spermine, spermidine and putrescine) in human saliva was developed. This method is based on pre-column derivatization with o-phthaldialdehyde (OPA). The derivatives were separated on a Nucleosil ODS column (250x4.6 mm I.D.; 5 microm). The gradient elution was performed with two mobile phases A (water) and B (methanol) at a flow rate of 0.8 ml/min. The column eluate was monitored by fluorescence detection (excitation, 360 nm; emission, 510 nm). The within- and between-assay coefficients of variation for all the compounds were below 5%. The detection limits for spermine, spermidine and putrescine were 0.04, 0.05 and 0.06 nmol/ml, respectively. The recovery was greater than 90%. Our analytical technique requires neither preliminary extraction with an organic solvent, nor long multi-step procedures. For saliva samples, this is a simple, rapid and highly reproducible method that can be easily applied to the routine determination of salivary polyamines, whose levels increase early in several pathological conditions.


Asunto(s)
Poliaminas Biogénicas/análisis , Cromatografía Líquida de Alta Presión/métodos , Saliva/química , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Fluorescencia
14.
Physiol Res ; 49(3): 363-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11043924

RESUMEN

Both prostaglandins (PGs) and vitamin E are known to deeply affect immune responses. It is shown here that they both influence T cell-mediated immunity through reciprocal interference on the expression of cyclic-AMP responsive element binding (CREB) family proteins. CREB1 protein of human T lymphocytes was significantly modulated by a brief treatment of 5 to 10 min with PGE2. On the contrary, vitamin E appeared to be ineffective on the CREB1 behavior, while it abolished the PGE2-induced modulation of this protein. The CREB2 protein expression was also affected by PGE2 treatment, but a longer period of incubation (>20 min) was needed to observe these changes. Vitamin E showed a strong enhancing effect on CREB2 that was partially reversed by the subsequent treatment with PGE2. Our results support the idea that there is reciprocal interference between PGE2 and vitamin E on PGE2-induced signals in T lymphocytes. These data are in agreement with the reports concerning different cell systems and experimental conditions.


Asunto(s)
Dinoprostona/farmacología , Linfocitos T/metabolismo , Factores de Transcripción/biosíntesis , Factores de Transcripción/metabolismo , Vitamina E/farmacología , Factor de Transcripción Activador 4 , Adulto , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Humanos , Immunoblotting , Linfocitos T/efectos de los fármacos , Factores de Transcripción/análisis
15.
Immunopharmacol Immunotoxicol ; 22(1): 117-29, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10737261

RESUMEN

The effects of Prostaglandin (PG) E2 treatment of human T lymphocytes on polyamine metabolism were investigated. PGE2 is known to inhibit lymphocyte proliferation, while polyamines play an important role in several biochemical processes leading to increased cell growth. Preincubation of T lymphocytes with PGE2 (10(-6) M) for 10 min was able to increase ornithine decarboxylase (ODC) activity and putrescine as well as spermine levels, while spermidine concentration was drastically reduced. After 30 and 60 min of treatment, a decrease in ODC activity and putrescine concentration was observed. On the contrary, the initial inhibition of spermine-N1-acetyltransferase (SAT) activity was followed by a progressive increase of this catabolic enzyme. These changes were related to modifications of cAMP concentrations. Our data may help clarify the mechanisms underlying the biphasic effect of PGE2, which ultimately leads to inhibition of cell proliferation.


Asunto(s)
Poliaminas Biogénicas/metabolismo , Dinoprostona/farmacología , Linfocitos T/metabolismo , Acetiltransferasas/biosíntesis , AMP Cíclico/metabolismo , Humanos , Técnicas In Vitro , Ornitina Descarboxilasa/biosíntesis , Putrescina/biosíntesis , Espermidina/biosíntesis , Espermina/biosíntesis , Linfocitos T/efectos de los fármacos , Linfocitos T/enzimología
16.
Artículo en Inglés | MEDLINE | ID: mdl-11799735

RESUMEN

A study has been carried out on the S.E.M. on the enamel of an albino rat's inferior incisor. The observations concern almost the entire ameloblastic cycle, specifically, from the end of the cellular differentiation phase (pre-ameloblasts III) to the end of the modulation phase. The authors have pointed out some morphogenetical variations which during the depositing phase, are manifested on the distal extremity of the cells and are concentrated at this level in the differentiation of the Tomes' processes. Successively, during the transitional post-secretory and cellular modulation phases, the morphogenetical differences at the distal extremities also involve the lateral walls of the ameloblasts and their spatial relationships. Some morphological differences are correlated with different functional moments and revealed by an examination of the corresponding superficial areas of the enamel in the course of its formation. In this study, the constant orientation of the perpendicular is evident at the secretion plane in opposition with other studies that propose a 'pendulum movement' theory of these cells during the depositing phase of the prismatic layers. In addition, a morphological classification is proposed consisting of four types of modulative ameloblasts.


Asunto(s)
Ameloblastos/fisiología , Amelogénesis/fisiología , Morfogénesis/fisiología , Ameloblastos/metabolismo , Ameloblastos/ultraestructura , Animales , Diferenciación Celular , Membrana Celular/fisiología , Membrana Celular/ultraestructura , Citoplasma/fisiología , Citoplasma/ultraestructura , Esmalte Dental/ultraestructura , Uniones Intercelulares/fisiología , Uniones Intercelulares/ultraestructura , Microscopía Electrónica de Rastreo , Microvellosidades/fisiología , Microvellosidades/ultraestructura , Ratas , Ratas Wistar , Vesículas Secretoras/fisiología , Vesículas Secretoras/ultraestructura
17.
Clin Immunol Immunopathol ; 87(2): 115-23, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9614925

RESUMEN

PGE2 treatment of mononuclear cells from patients with different types of neoplasias was unable to decrease either the number of plaque-forming cells or the expression of CD71 and CD25 in PWM-driven cultures. In contrast, in previous studies, PGE2 inhibited these parameters in cultured mononuclear cells from normal volunteers. Surgical treatment of cancer patients did not modify the lymphocyte sensitivity to PGE2 after 1 week, but at 2 and 6 months after therapeutical treatment, the inhibition values of the parameters studied were almost similar or very similar to those of normal lymphocytes. The reduction of PGE2 sensitivity in cancer patients was related to the increase of PGE2 levels and, probably, to a PGE2 receptor saturation. A restoration of PGE2-induced inhibition some months after therapy could be due to the decrease in PGE2 levels and to receptor unsaturation.


Asunto(s)
Dinoprostona/farmacología , Activación de Linfocitos/efectos de los fármacos , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Neoplasias/sangre , Neoplasias/inmunología , Mitógenos de Phytolacca americana/antagonistas & inhibidores , Mitógenos de Phytolacca americana/farmacología , Antígenos CD/biosíntesis , Antígenos CD/sangre , Antígenos de Diferenciación de Linfocitos B/biosíntesis , Antígenos de Diferenciación de Linfocitos B/sangre , Células Cultivadas , Interacciones Farmacológicas , Femenino , Humanos , Linfocitos/metabolismo , Masculino , Neoplasias/cirugía , Receptores de Interleucina-2/biosíntesis , Receptores de Interleucina-2/sangre , Receptores de Transferrina , Sensibilidad y Especificidad , Estimulación Química
18.
Cell Immunol ; 174(1): 99-105, 1996 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-8929459

RESUMEN

Prostaglandins of the E series are immunomodulatory agents which exert inhibitory as well as stimulatory effects on a variety of immune responses. Since it is known that PGE2 is able to increase cAMP levels, we investigated whether it can affect gene expression through the activation of the transcription factors which bind enhancer elements in the promoter regions of cAMP-regulated genes. Using electrophoretic mobility shift assay, we demonstrated that a short treatment of human T lymphocytes with PGE2 induces specific binding activity to CRE and AP-2, but not AP-1, DNA elements. Since the okadaic acid, a potent protein phosphatase inhibitor, prolongs the induction of the binding activity, phosphorylation events are likely to occur. This activity seems to be due to increased cAMP levels because forskolin and IBMX mimic the effects of PGE2. More interestingly, transfection experiments with CRE-CAT plasmide show that PGE2 activates the transcription of a CRE-containing promoter. These data support the positive role for PGE2 on some immune functions.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas de Unión al ADN/metabolismo , Dinoprostona/farmacología , Elementos de Facilitación Genéticos , Linfocitos T/metabolismo , Factores de Transcripción/metabolismo , 1-Metil-3-Isobutilxantina/farmacología , Sitios de Unión , Colforsina/farmacología , AMP Cíclico/metabolismo , ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Células Jurkat , Ácido Ocadaico/farmacología , Fosforilación , Regiones Promotoras Genéticas , Linfocitos T/efectos de los fármacos , Factor de Transcripción AP-2 , Transfección
19.
Immunopharmacol Immunotoxicol ; 18(1): 27-36, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8683037

RESUMEN

Prostaglandins (PGs) are generally known to exert inhibitory as well as some enhancing effects on the immune system. This study was performed to assess the influence of the exogenous PGs and cyclic adenosine monophosphate (cAMP)-elevating agents on cytokine production by PWM-stimulated human T lymphocytes. Peripheral blood T lymphocytes from healthy donors were pretreated for 30 min at 25 degrees C with PGE2 (10(-4) to 10(-7) M) PGF1 alpha, IBMX or Forskolin (10(-4) to 10(-5) M) and cultured for 7 days in the presence of Pokeweed Mitogen (PWM), PGE2, IBMX and Forskolin, but not PGF1 alpha, significantly increased IL-6 production while inhibited IL-2, IL-3, IL-4, IFN-gamma, TNF-alpha and GM-CSF production. Our data indicate that cAMP-elevating agents can profoundly affect cytokine secretion by T cells in PWM-driven cultures and that this effect is dose-dependent. The results reported here are compatible with the existence of separate pathways of gene induction for IL-2, IL-3, IL-4, IFN-gamma, TNF-alpha and GM-CSF on the one hand and IL-6 on the other one.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Citocinas/biosíntesis , Citocinas/fisiología , Dinoprostona/farmacología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Células Cultivadas , AMP Cíclico/biosíntesis , Citocinas/sangre , Humanos , Linfocitos T/efectos de los fármacos
20.
Immunopharmacol Immunotoxicol ; 17(2): 311-21, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7650293

RESUMEN

The effects of prostaglandins on superoxide generation by neutrophils were investigated, since these arachidonic acid metabolites are both involved in the early phase of the inflammatory process and during later stages of neutrophil function. Preincubation of these cells for five minutes with concentrations of PGE2 ranging from 10(-7) to 10(-4) M was able to significantly reduce superoxide production in PMA-stimulated neutrophils. Other pro-inflammatory PGs tested, such as PGE1, PGF1 alpha, PGF2 alpha, inhibited the respiratory burst. The PGE2-induced inhibition was compared to that exerted by staurosporine, a PKC inhibitor. The effects of the two drugs were not additive, since the combinations of PGE2 and staurosporine reduced O2- production to the same extent as staurosporine alone. Possible interferences between PKA- and PKC-mediated transduction signals are discussed.


Asunto(s)
Dinoprostona/farmacología , Neutrófilos/efectos de los fármacos , Estallido Respiratorio/efectos de los fármacos , Alcaloides/farmacología , Células Cultivadas , Humanos , Neutrófilos/metabolismo , Prostaglandinas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Estaurosporina , Superóxidos/análisis , Superóxidos/metabolismo
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