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1.
J Hosp Infect ; 140: 90-95, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37562590

RESUMO

OBJECTIVES: To compare intensivist-diagnosed ventilator-associated pneumonia (iVAP) with four established definitions, assessing their agreement in detecting new episodes. METHODS: A multi-centric prospective study on pulmonary microbiota was carried out in patients requiring mechanical ventilation (MV). Data collected were used to compare hypothetical VAP onset according to iVAP with the study consensus criteria, the European Centre for Disease Control and Prevention definition, and two versions of the latter adjusted for leukocyte count and fever. RESULTS: In our cohort of 186 adult patients, iVAPs were 36.6% (68/186, 95% confidence interval 30.0-44.0%), with an incidence rate of 4.64/100 patient-MV-days, and median MV-day at diagnosis of 6. Forty-seven percent of patients (87/186) were identified as VAP by at least one criterion, with a median MV-day at diagnosis of 5. Agreement between intensivist judgement (iVAP/no-iVAP) and the criteria was highest for the study consensus criteria (50/87, 57.4%), but still one-third of iVAP were not identified and 9% of patients were identified as VAP contrary to intensivist diagnosis. VAP proportion differed between criteria (25.2-30.1%). CONCLUSIONS: Caution is needed when evaluating studies describing VAP incidence. Pre-agreed criteria and definitions that capture VAP's evolving nature provide greater consistency, but new clinically driven definitions are needed to align surveillance and diagnostic criteria with clinical practice.


Assuntos
Pneumonia Associada à Ventilação Mecânica , Adulto , Humanos , Pneumonia Associada à Ventilação Mecânica/diagnóstico , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Respiração Artificial/efeitos adversos , Estudos Prospectivos , Dados Preliminares , Incidência , Unidades de Terapia Intensiva
2.
Neoplasma ; 66(6): 963-970, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31607128

RESUMO

Triple negative breast cancer (TNBC) is a particularly aggressive subtype of breast cancer (BC) for which limited therapeutic options are available. Recently, ß-blockers (BBs) have been suggested to have favorable effects in the treatment of BC. The aim of this systematic review was to collect evidence from preclinical and clinical studies concerning the scientific evidence for the repurposing of BBs in TNBC treatment. PubMed database was searched to retrieve studies of interest published up to 30/01/2018. All preclinical studies using TNBC in vitro and in vivo models and assessing the effect of any molecule with sympatholytic or sympathomimetic activity on adrenergic receptors were included. Clinical studies concerning BBs were considered eligible. The Newcastle-Ottawa scale was used for the quality assessment of clinical studies. A total of 614 study references were retrieved. Forty-six preclinical studies were included. In in vitro studies, propranolol, a non-selective BB, significantly decreased proliferation, migration and invasion of TNBC cells. Consistently, in in vivo studies, propranolol inhibited metastasis, angiogenesis and tumor growth. Clinical studies, reporting evidence from a total of four distinct retrospective observational cohort studies, showed a beneficial effect of BBs in TNBC treatment. The overall quality of the clinical evidence collected was low. Preclinical evidence collected in this systematic review are in line with the results reported in the clinical studies retrieved, pointing towards a beneficial effect of BB in the treatment of TNBC. However, given the overall low quality of available evidence, no definite conclusion may be drawn.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Reposicionamento de Medicamentos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neovascularização Patológica , Estudos Observacionais como Assunto , Estudos Retrospectivos
3.
Oxid Med Cell Longev ; 2018: 9765027, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538807

RESUMO

Endothelial cells (ECs) are dynamic cells that turn from growth into senescence, the latter being associated with cellular dysfunction, altered metabolism, and age-related cardiovascular diseases. Aldehyde dehydrogenase 2 (ALDH2) is a mitochondrial enzyme metabolizing acetaldehyde and other toxic aldehydes, such as 4-hydroxynonenal (4-HNE). In conditions in which lipid peroxidation products and reactive oxygen species (ROS) are accumulated, ECs become dysfunctional and significantly contribute to the progression of vascular-dependent diseases. The aim of the present study has been to investigate whether inhibition of ALDH2 alters endothelial functions together with the impairment of bioenergetic functions, accelerating the acquisition of a senescent phenotype. HUVECs transfected with siRNA targeting ALDH2 or treated with daidzin, an ALDH2 inhibitor, were used in this study. We observed an alteration in cell morphology associated with endothelial dysfunctions. Loss of ALDH2 reduced cell proliferation and migration and increased paracellular permeability. To assess bioenergetic function in intact ECs, extracellular flux analysis was carried out to establish oxygen consumption rates (OCR). We observed a decrease in mitochondrial respiration and reserve capacity that coincided with SA-ß-Gal accumulation and an increase in p21 and p53 expression in siALDH2 or daidzin-treated HUVECs. Treatment with N-acetyl-L-cysteine (NAC) reduced endothelial dysfunctions mediated by siALDH2, indicating that oxidative stress downstream to siALDH2 plays an instrumental role. Our results highlight that ALDH2 impairment accelerates the acquisition of a premature senescent phenotype, a change likely to be associated with the observed reduction of mitochondrial respiration and reserve capacity.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Respiração Celular/fisiologia , Senescência Celular/fisiologia , Células Endoteliais da Veia Umbilical Humana/enzimologia , Mitocôndrias/metabolismo , Humanos
4.
Plant Biol (Stuttg) ; 16(3): 607-14, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23957505

RESUMO

The contribution of antioxidant defence systems in different tolerance to direct and bicarbonate-induced Fe deficiency was evaluated in two pea cultivars (Kelvedon, tolerant and Lincoln, susceptible). Fe deficiency enhanced lipid peroxidation and H2 O2 concentration in roots of both cultivars, particularly in the sensitive one grown under bicarbonate supply. The results obtained on antioxidant activities (SOD, CAT, POD) suggest that H2 O2 accumulation could be due to an overproduction of this ROS and, at the same time, to a poor capacity to detoxify it. Moreover, under bicarbonate supply the activity of POD isoforms was reduced only in the sensitive cultivar, while in the tolerant one a new isoform was detected, suggesting that POD activity might be an important contributor to pea tolerance to Fe deficiency. The presence of bicarbonate also resulted in stimulation of GR, MDHAR and DHAR activities, part of the ASC-GSH pathway, which was higher in the tolerant cultivar than in the sensitive one. Overall, while in the absence of Fe only slight differences were reported between the two cultivars, the adaptation of Kelvedon to the presence of bicarbonate seems to be related to its greater ability to enhance the antioxidant response at the root level.


Assuntos
Antioxidantes/metabolismo , Deficiências de Ferro , Pisum sativum/fisiologia , Raízes de Plantas/fisiologia , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Glutationa/metabolismo , Hidrazonas/metabolismo , Peróxido de Hidrogênio/metabolismo , Ferro/farmacologia , Isoenzimas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Pisum sativum/enzimologia , Pisum sativum/crescimento & desenvolvimento , Pisum sativum/metabolismo , Peroxidase/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Especificidade por Substrato/efeitos dos fármacos , Superóxido Dismutase/metabolismo
5.
Oncogene ; 31(29): 3457-66, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22081067

RESUMO

In this report we describe the contribution of prostaglandin E(2) (PGE(2)) derived from the inducible microsomal PGE-synthase type-1 (mPGES-1) to the epidermal growth factor receptor (EGFR) oncogenic drive in tumor epithelial cells and in tumor-bearing mice. EGFR stimulation upregulated expression of mPGES-1 in HT-29, A431 and A549 cancer cells. Egr-1, a transcription factor induced by EGF, mediated this response. The Egr-1 rise provoked the overexpression of mPGES-1 messenger and protein, and enhanced PGE(2) formation. These changes were suppressed either by silencing Egr-1, or by upstream blockade of EGFR or ERK1/2 signals. Further, in a clonogenic assay on tumor cells, EGF induced a florid tumorigenic phenotype, which regressed when mPGES-1 was silenced or knocked down. EGF-induced mPGES-1 overexpression in epithelial cell reduced E-cadherin expression, whereas enhancing that of vimentin, suggesting an incipient mesenchymal phenotype. Additionally, inhibiting the EGFR in mice bearing the A431 tumor, the mPGES-1 expression and the tumor growth, exhibited a parallel decline. In conclusion, these findings provide novel evidence that a tight cooperation between the EGF/EGFR and mPGES-1 leads to a significant tumorigenic gain in epithelial cells, and provide clues for controlling the vicious association.


Assuntos
Receptores ErbB/metabolismo , Oxirredutases Intramoleculares/genética , Transdução de Sinais , Regulação para Cima , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Ativação Enzimática/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Feminino , Inativação Gênica , Humanos , Oxirredutases Intramoleculares/deficiência , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Prostaglandina-E Sintases , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
6.
Patient Prefer Adherence ; 4: 33-44, 2010 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-20361064

RESUMO

OBJECTIVES: The Italian National Institute of Health Quality of Life - Core Evaluation Form (ISSQoL-CEF) is a specific questionnaire measuring health-related quality of life for human immunodeficiency virus-infected people in the era of highly active antiretroviral therapy. The main goal of this study was to examine the construct validity of this questionnaire by confirmation of its hypothesized dimensional structure. METHODS: Baseline quality of life data from four clinical studies were collected and a confirmatory factor analysis of the ISSQoL-CEF items was carried out. Both first-order and second-order factor models were tested: Model 1 with nine correlated first-order factors; Model 2 with three correlated second-order factors (Physical, Mental, and Social Health); Model 3 with two correlated second-order factors (Physical and Mental/Social Health); Model 4 with only one second-order factor (General Health). RESULTS: A total of 261 patients were surveyed. Model 1 had a good fit to the data. Model 2 had an acceptable fit to the data and it was the best of all hierarchical models. However, Model 2 fitted the data worse than Model 1. CONCLUSIONS: The findings of in this study, consistent with the results of previous study, pointed out the construct validity of the ISSQoL-CEF.

7.
Biologics ; 2(3): 577-81, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19707388

RESUMO

AIM: To evaluate the impact of health-related quality of life (HRQoL) enfuvirtide-based (ENF-based) salvage regimens of treatment-experienced HIV patients, in an observational multicenter cohort study. METHODS: HRQoL was measured in a cohort of 16 patients over a 6-month follow-up using 2 instruments: the ISSQoL (Istituto Superiore di Sanità Quality of Life), a recently validated HIV-specific questionnaire; the EQ-5D (EuroQol), a generic widely used instrument. ENF was given at standard dosage along with an optimized background regimen. RESULTS: Most of HRQoL dimensions showed improvement in ENF-treated patients at the post-baseline time points. Social functioning was the only dimension showing a negative effect. Monthly care costs of antiretroviral drugs for HIV patients taking ENF plus an optimized background regimen were approximately euro2,348 per patient-month (range euro382-euro2,940). CONCLUSION: Our results show that the addition of ENF to an optimized background salvage-HAART may positively affect HRQoL not only in clinical trials but also in a sample population of patients used in a routine clinical practice.

8.
FEBS Lett ; 581(4): 702-6, 2007 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-17274989

RESUMO

Oxidative stress is one of the factor contributing to blood brain barrier degeneration. This phenomenon is observed during pathological conditions such as Alzheimer's disease or cerebral amyloid angiopathy in which brain haemorrhages are very frequent. Both diseases are characterized by beta amyloid peptide deposition either in neurons or in vessels. Oxidative stress leads to impairment of mitochondrial functions and apoptotic cell death subsequent to caspases activation. In this paper we demonstrate that BH4 domain of Bcl-xl administrated to endothelial cells as the conjugated form with TAT peptide, reverts Abeta-induced apoptotic cell death by activating a survival programme which is Akt/endothelial nitric oxide synthase dependent.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Endotélio Vascular/efeitos dos fármacos , Produtos do Gene tat/farmacologia , Fragmentos de Peptídeos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Endotélio Vascular/enzimologia , Ativação Enzimática/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Estrutura Terciária de Proteína/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Cell Death Differ ; 13(7): 1088-96, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16410806

RESUMO

Recent evidences suggest that Abeta peptides modulate endothelial cell (EC) functions. At low concentrations, Abeta1-40 enhances the pro-angiogenic activity of FGF-2, whereas deposition of excess Abeta causes EC dysfunction and cerebral amyloid angiopathy (CAA). We investigated whether FGF-2 attenuates EC dysfunction caused by pathological Abeta levels. We studied Abeta1-40 on EC survival, as well as on signals responsible of their angiogenic phenotype. At 5-50 microM Abeta1-40 reduced EC population, caused apoptosis, downregulated FGF-2 production, inhibited FGF-2 binding to heparin, and FGFR1 phosphorylation. Toxic effects were owing to lack of FGF-2 stimulation, as EC overexpressing FGF-2 displayed extraordinary resistance to Abeta1-40 injuries. The FGF-2 mechanism responsible for reversing damages, involves the downstream enhancement of Akt, a pathway independent of eNOS activation. In conclusion, we demonstrate that FGF-2 protects EC from the effects of excess Abeta1-40, suggesting that it may attenuate the consequences of Abeta deposition in pathologies as CAA.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Células Endoteliais/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fragmentos de Peptídeos/farmacologia , Animais , Western Blotting , Células CHO , Caspase 3 , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cricetinae , Cricetulus , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/genética , Humanos , Camundongos , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
10.
J Vasc Res ; 41(2): 202-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15031604

RESUMO

BACKGROUND: Vascular endothelium undergoes apoptosis when exposed to reactive oxygen species (ROS), including hydrogen peroxide and superoxide radicals. ROS are believed to be the cause of damage to small vessels during ischemia-reperfusion injury and of arterial damage during atherosclerosis. Hydrogen peroxide-induced apoptosis is mediated through the inhibition of Bcl-xl activity and caspase-3 and caspase-9 activation. The BH4 domain of the Bcl-2 family members is responsible for their antiapoptotic activity. The BH4 domains of Bcl-2 and Bcl-xl inhibit cytochrome c release and the loss of mitochondrial membrane potential. METHODS AND RESULTS: The purpose of this project was to study the antiapoptotic effect of cell-permeant derivative of Bcl-2 (BH4 peptide) on endothelial cells exposed to stress conditions. BH4 peptide was conjugated to the cell-permeable peptide TAT and was applied to endothelial cells under conditions of serum starvation and hydrogen peroxide treatment. TAT-BH4 reduced caspase-3 activity and prevented apoptotic cell death. CONCLUSION: Our results indicate that TAT-BH4 peptide can protect endothelial cells from ROS-induced apoptosis.


Assuntos
Apoptose/fisiologia , Vasos Coronários/citologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Aorta/citologia , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Peróxido de Hidrogênio/farmacologia , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-bcl-2/química , Suínos , Veias Umbilicais/citologia
11.
Br J Cancer ; 88(9): 1484-91, 2003 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-12778081

RESUMO

The nitric oxide synthase (NOS) pathway has been clearly demonstrated to regulate angiogenesis. Increased levels of NO correlate with tumour growth and spreading in different experimental and human cancers. Drugs interfering with the NOS pathway may be useful in angiogenesis-dependent tumours. The aim of this study was to pharmacologically characterise certain ruthenium-based compounds, namely NAMI-A, KP1339, and RuEDTA, as potential NO scavengers to be used as antiangiogenic/antitumour agents. NAMI-A, KP1339 and RuEDTA were able to bind tightly and inactivate free NO in solution. Formation of ruthenium-NO adducts was documented by electronic absorption, FT-IR spectroscopy and (1)H-NMR. Pretreatment of rabbit aorta rings with NAMI-A, KP1339 or RuEDTA reduced endothelium-dependent vasorelaxation elicited by acetylcholine. This effect was reversed by 8-Br-cGMP. The key steps of angiogenesis, endothelial cell proliferation and migration stimulated by vascular endothelial growth factor (VEGF) or NO donor drugs, were blocked by NAMI-A, KP1339 and RuEDTA, these compounds being devoid of any cytotoxic activity. When tested in vivo, NAMI-A inhibited angiogenesis induced by VEGF. It is likely that the antitumour properties previously observed for ruthenium-based NO scavengers, such as NAMI-A, are related to their NO-related antiangiogenic properties.


Assuntos
Inibidores da Angiogênese/farmacologia , Dimetil Sulfóxido/análogos & derivados , Dimetil Sulfóxido/farmacologia , Endotélio Vascular/fisiologia , Óxido Nítrico/fisiologia , Compostos Organometálicos/farmacologia , Compostos de Rutênio/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Vasos Coronários , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Sequestradores de Radicais Livres , Humanos , Óxido Nítrico Sintase/antagonistas & inibidores , Espectroscopia de Infravermelho com Transformada de Fourier , Vênulas/efeitos dos fármacos , Vênulas/fisiologia
12.
J Vasc Res ; 38(4): 389-97, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11455210

RESUMO

Fibroblast growth factor-2 (FGF2) and vascular endothelial growth factor (VEGF) exert their angiogenic activity by interacting with endothelial cells in a distinct manner. In this study, we investigated the morphological features of endothelial cells of the chick embryo chorioallantoic membrane (CAM) microvasculature after stimulation with FGF2 or VEGF. In order to provide a continuous delivery of the growth factor, we utilized a recently developed gelatin sponge/CAM assay in which a limited number of FGF2- or VEGF-transfected cells were adsorbed onto gelatin sponges and applied on the top of the CAM on day 8 of development. Their angiogenic activity was compared to that exerted by a single bolus of the corresponding growth factor. All the angiogenic stimuli induced a comparable vasoproliferative response, as demonstrated by the appearance of similar numbers of immature blood vessels within the sponge on day 12. No angiogenic response was observed in CAMs implanted with the corresponding parental cell lines or vehicle. Electron microscopy demonstrated that VEGF-overexpressing cells modified the phenotype of the endothelium of the blood vessels at the boundary between the implant and the surrounding CAM mesenchyme. The endothelial lining of 30% of these vessels showed segmental attenuations, was frequently interrupted and became fenestrated, mimicking what is observed in tumor vasculature. In contrast, the vessels consisted of continuous endothelium sealed by tight junctions in all the other experimental conditions. These results indicate that FGF2 and VEGF interact with endothelial cells of the CAM in a distinct manner. Both growth factors induce a potent angiogenic response, but only VEGF delivered in a continuous manner by its transfectants can modify the phenotype of the otherwise quiescent endothelium of CAM blood microvessels. The gelatin sponge/CAM assay may constitute a new model to study the mechanisms leading to endothelial fenestration in tumor growth.


Assuntos
Alantoide/irrigação sanguínea , Córion/irrigação sanguínea , Fatores de Crescimento Endotelial/administração & dosagem , Endotélio Vascular/citologia , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Linfocinas/administração & dosagem , Neovascularização Fisiológica , Adsorção , Animais , Aorta , Capilares/fisiologia , Capilares/ultraestrutura , Linhagem Celular , Transplante de Células/métodos , Embrião de Galinha , Fatores de Crescimento Endotelial/genética , Endotélio Vascular/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Gelatina , Expressão Gênica , Linfocinas/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/administração & dosagem , Fatores de Tempo , Transfecção , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
14.
Int J Biochem Cell Biol ; 33(4): 305-13, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11312101

RESUMO

The role of nitric oxide (NO) in the induction of angiogenesis was evaluated in a murine heart endothelioma cell line (H.end.FB) carrying the mT oncogene. Two clonal derivatives of H.end.FB, H80 and H73, exhibiting different NO synthase (NOS) activities were selected and used in the study. The relationship among NOS activity and tumor cell behaviour (growth, and angiogenic capacity) and the molecular control of gene expression were investigated. H.end.FB and H80 on one side and H73 on the other side exhibited the highest and lowest NOS activity, respectively. Cell growth was inversely correlated to the amount of NO produced by the cell lines. Conversely, in the avascular rabbit cornea assay, H.end.FB and H80 cells were strongly angiogenic, while H73 were poorly angiogenic, indicating that the ability of the cells to induce neovascularization was associated with the extent of NO produced. Consistently, systemic administration to rabbits of the NOS inhibitor N(w)-nitro-L-arginine methyl ester (L-NAME) significantly reduced the angiogenicity of H.end.FB cells. RT-PCR evidenced that H.end.FB expressed mRNA for TGF-beta1 and all VEGF isoforms, VEGF165 being predominantly expressed. NOS inhibition reduced the basal expression of VEGF isoforms, while it markedly potentiated TGF-beta1 expression. These results indicate that the endogenous production of NO in tumor cells can serve as an autocrine/paracrine signalling mechanism of progression, by controlling angiogenic factor/modulator expression.


Assuntos
Neovascularização Fisiológica/fisiologia , Óxido Nítrico/fisiologia , Proteínas Oncogênicas/fisiologia , Animais , Linhagem Celular Transformada , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Camundongos , Óxido Nítrico Sintase/antagonistas & inibidores , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
15.
J Pharmacol Exp Ther ; 296(3): 869-75, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11181918

RESUMO

The vasodilator activity of alpha(1)-adrenoceptor agonists was tested in the rat mesenteric vascular bed (MVB), and the mechanism involved was investigated in cultured endothelial cells isolated from the bovine coronary vascular bed. In preparations preconstricted by U46619, noradrenaline and phenylephrine induced a slight relaxant effect at nanomolar concentrations. This effect was abolished in endothelium-denuded preparations and in preparations pretreated with 100 microM N(omega)-nitro-L-arginine methyl ester plus 3 microM indomethacin. Both the phospholipase C inhibitor U73122 and the endoplasmic reticulum Ca(2+)-ATPase inhibitor thapsigargin inhibited the vasorelaxant effect of phenylephrine. The cellular level of inositol monophosphate (IP(1)) in bovine endothelial cells doubled after a 15-min exposure to 0.03 to 0.1 nM phenylephrine. The activity of cNOS was significantly increased following exposure to the same concentrations of phenylephrine. Both chloroethylclonidine and the selective alpha(1D)-adrenoceptor antagonist BMY 7378 reduced, in a concentration-dependent manner, the relaxant effect induced by phenylephrine, whereas the selective alpha(1A)-adrenoceptor antagonist (+)-niguldipine was ineffective. BMY 7378 also blocked the cNOS activation induced by phenylephrine. Conversely, the increase in perfusion pressure induced by micromolar concentrations of phenylephrine was blocked by 1 nM (+)-niguldipine, but was unaffected by BMY 7378. These findings demonstrate that nanomolar concentrations of phenylephrine, which are devoid of any contractile effect, induced a slight endothelium-dependent vasorelaxation in the rat MVB through the stimulation of alpha(1D)-adrenoceptors, located on endothelial cells, which act through phospholipase C stimulation, followed by IP(1) generation, and nitric-oxide synthase activation. Conversely, the increase in perfusion pressure induced by micromolar concentrations of phenylephrine is attributable to the stimulation of alpha(1A)-adrenoceptors.


Assuntos
Endotélio Vascular/fisiologia , Artérias Mesentéricas/fisiologia , Receptores Adrenérgicos alfa 1/fisiologia , Vasodilatação/fisiologia , Agonistas de Receptores Adrenérgicos alfa 1 , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Bovinos , Células Cultivadas , Interações Medicamentosas , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Fosfatos de Inositol/metabolismo , Artérias Mesentéricas/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Norepinefrina/farmacologia , Fenilefrina/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Isoformas de Proteínas/fisiologia , Pirrolidinonas/farmacologia , Ratos , Ratos Wistar , Transdução de Sinais , Circulação Esplâncnica , Tapsigargina/farmacologia , Vasodilatação/efeitos dos fármacos
16.
Am J Physiol Heart Circ Physiol ; 280(1): H99-H107, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11123223

RESUMO

We examined the possible cooperation between norepinephrine (NE) and ANG II on proliferation of cultured vascular smooth muscle cells (VSMCs) and the involved cellular mechanisms. Nanomolar NE concentrations stimulated VSMC proliferation through a prazosin-sensitive effect. The pretreatment of cells with 100 nM ANG II for 24 h significantly potentiated the NE-induced VSMC proliferation; this potentiating effect of ANG II was blocked by losartan but was unaffected by the AT(2) receptor antagonist PD-123177. ANG II pretreatment also potentiated the increase in inositol phosphate turnover and upregulated the cell expression of fibroblast growth factor (FGF-2) induced by NE. Anti-FGF-2 neutralizing antibodies prevented the potentiating effect of ANG II on NE-induced cell growth. Both ANG II and NE stimulated extracellular signal-related kinase (ERK1) activation, but an ANG II potentiation of the effect of NE on ERK1 activity was not detectable. Moreover, ANG II significantly increased protein synthesis but did not potentiate the hypertrophic effect of NE. These findings demonstrate that ANG II and NE cooperate in promoting VSMC growth and that FGF-2 upregulation is involved in this effect.


Assuntos
Angiotensina II/fisiologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , Substâncias de Crescimento/fisiologia , Músculo Liso Vascular/citologia , Norepinefrina/fisiologia , Angiotensina II/farmacologia , Animais , Aorta Torácica/citologia , Western Blotting , Contagem de Células , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Ativação Enzimática , Fator 2 de Crescimento de Fibroblastos/metabolismo , Hipertrofia , Fosfatos de Inositol/metabolismo , Masculino , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Norepinefrina/farmacologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vasoconstritores/farmacologia
17.
Blood ; 96(7): 2568-73, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11001913

RESUMO

Because of its immunosuppressive properties, interleukin-10 (IL-10) is thought to play an important role in a number of human disease states, including inflammation, autoimmunity, and transplant rejection. In this study, we demonstrate that introduction of human or viral IL-10 genes into Burkitt's lymphoma cells markedly reduced their ability to grow as subcutaneous (sc) tumors in SCID mice. In vivo assays for angiogenesis revealed an inhibition of the angiogenic capacity of the IL-10-transfected lines. Recombinant human IL-10 abolished and viral IL-10 reduced vascular endothelial growth factor (VEGF)-165-induced neovascularization. Furthermore, IL-10 blocked the VEGF- and fibroblast growth factor (FGF)-2-induced proliferation of microvascular endothelial cells in vitro. The current observations suggest a direct role for IL-10 in the prevention of angiogenesis in human lymphoid malignancies.


Assuntos
Linfoma de Burkitt/patologia , Interleucina-10/genética , Interleucina-10/fisiologia , Neovascularização Patológica/prevenção & controle , Animais , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/prevenção & controle , Divisão Celular , Linhagem Celular , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/citologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica , Interleucina-10/farmacologia , Células Matadoras Naturais/imunologia , Linfocinas/farmacologia , Camundongos , Camundongos SCID , Transplante de Neoplasias , Coelhos , Proteínas Recombinantes/farmacologia , Transfecção , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
J Leukoc Biol ; 68(2): 260-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10947071

RESUMO

We evaluated the synthesis of nitric oxide (NO) and of the neurotoxic kynurenine metabolites 3OH-kynurenine and quinolinic acid (QUIN) in interferon-gamma (IFN-gamma)-activated macrophages of the murine BACl.2F5 cell line with the aim of investigating the roles of mononuclear phagocytes in inflammatory neurological disorders. IFN-gamma induced indoleamine 2,3-dioxygenase (IDO) and NO synthase (NOS) and increased the synthesis of 3OH-kynurenine, QUIN, and NO that accumulated in the incubation medium where they reached neurotoxic levels. Macrophage exposure to norharmane, an IDO inhibitor, resulted in a decreased formation of not only the kynurenine metabolites but also NO. The inhibition of NO synthesis could not be ascribed to reduced NADPH availability or decreased NOS induction. Norharmane inhibited NOS activity also in coronary vascular endothelial cells and in isolated aortic rings. Our findings suggest that activated macrophages release large amounts of neurotoxic molecules and that norharmane may represent a prototype compound to study macrophage involvement in inflammatory brain damage.


Assuntos
Interferon gama/farmacologia , Cinurenina/biossíntese , Ativação de Macrófagos , Macrófagos/fisiologia , Óxido Nítrico Sintase/fisiologia , Ácido Quinolínico/metabolismo , Triptofano Oxigenase/fisiologia , Animais , Linhagem Celular , Indolamina-Pirrol 2,3,-Dioxigenase , Ativação de Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Triptofano Oxigenase/antagonistas & inibidores
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