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1.
J Mass Spectrom ; 55(5): e4492, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31896171

RESUMO

In the middle of the 1960s, I began graduate school and at the same time started on the path of using mass spectrometry to gain insight into various aspects of lipid biochemistry. This was not a straight path but one that went from organic geochemistry, to lunar sample analysis, to a pursuit of the structure of an elusive and very active, lipid mediator slow reacting substance of anaphylaxis (SRS-A). The discovery of the structure of SRS-A opened important questions about phospholipid biochemistry and the arachidonate cycle in cells. I have written this reflection to highlight the various advances in mass spectrometry that occurred during this time that had a great impact on our ability to study lipid biochemistry. I specifically applied these new advances to studies of leukotriene biosynthesis in vivo, leukotriene metabolism, and arachidonate-containing phospholipids that are essential in providing arachidonic acid for the 5-lipoxygenase pathway. Along the way, imaging mass spectrometry was shown to be a powerful tool to probe lipids as they exist in tissue slices. We found this as just one of the ways to use the emerging technology of lipidomics to study human pathophysiology. Our studies of neutral lipids and oxidized phospholipids were especially challenging due to the total number of molecular species that could be found in cells. Many challenges remain in using mass spectrometry for lipid studies, and a few are presented.


Assuntos
Metabolismo dos Lipídeos , Lipídeos/análise , Espectrometria de Massas/métodos , Animais , Ácido Araquidônico/análise , Ácido Araquidônico/metabolismo , Colorado , História do Século XX , História do Século XXI , Humanos , Leucotrienos/análise , Leucotrienos/metabolismo , Espectrometria de Massas/história , Espectrometria de Massas/instrumentação , Fosfolipídeos/análise , Fosfolipídeos/metabolismo , SRS-A/análise , SRS-A/metabolismo
2.
Respir Investig ; 57(2): 97-110, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30600174

RESUMO

The steps leading to the discovery of leukotrienes and the researchers that played a major part in this long process are presented. The pharmacology of these exquisitely potent compounds shows that they express bronchoconstrictor activity and numerous cellular effects via very specific receptors. Experimental evidence strongly suggests that these mediators play a significant role in asthma physiopathology. Numerous approaches were taken to block their effects on the lungs and this led to the discovery of selected drugs used for asthma treatment. The complexity of this disease and its treatment is emphasized.


Assuntos
Asma/etiologia , Leucotrienos , Terapia de Alvo Molecular , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Asma/tratamento farmacológico , Asma/metabolismo , Asma/patologia , Dietilcarbamazina/farmacologia , Cobaias , Humanos , Leucotrienos/metabolismo , Prostaglandinas/metabolismo , SRS-A/metabolismo
3.
Theriogenology ; 83(8): 1328-37, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25707327

RESUMO

The effect of leukotriene (LT) C4 (LTC4) and LTD4 on the contractility of an inflamed porcine uterus was investigated. On Day 3 of the estrous cycle (Day 0 of the study), either saline or Escherichia coli suspension was injected into each uterine horn. Although acute endometritis developed in all bacteria-inoculated gilts, a severe acute endometritis was noted more often on Day 8 than on Day 16. Myometrial and endometrial/myometrial strips were incubated with LTC4 or LTD4 alone, or together with a cysteinyl-LT receptor antagonist (BAY-u9773). Leukotriene C4 increased the contraction intensity in the saline- and bacteria-treated uteri on Day 8; however, its effect was lower in the myometrium of inflamed uteri. Contraction frequency was found to decrease in the saline-treated uteri as opposed to inflamed ones, in which it was elevated. On Day 16, contraction intensity increased in response to LTC4 in the saline-treated uteri but was reduced in the inflamed organs. The value of this parameter was lower in the inflamed uteri than that in the saline-treated ones. Leukotriene D4 (Days 8 and 16) augmented contractility in the saline-treated uteri, but despite increasing its intensity in the inflamed organs, it decreased contraction frequency. Leukotriene C4 or LTD4, added to BAY-u9773-pretreated saline- and bacteria-treated uteri on both days, decreased the contraction intensity. On Day 16 after treatment with BAY-u9773 and LTC4, contraction intensity in the endometrium/myometrium of the inflamed uteri was lower than that in the saline-treated organs. Data show that both LTC4 and LTD4 affect the contractility of inflamed porcine uteri, though LTC4 exerts a weaker contractile effect.


Assuntos
Endometrite/veterinária , Leucotrieno C4/farmacologia , Leucotrieno D4/farmacologia , Doenças dos Suínos/fisiopatologia , Contração Uterina/efeitos dos fármacos , Animais , Endometrite/microbiologia , Endometrite/fisiopatologia , Endométrio/fisiopatologia , Escherichia coli , Infecções por Escherichia coli/fisiopatologia , Infecções por Escherichia coli/veterinária , Feminino , Leucotrieno C4/antagonistas & inibidores , Miométrio/fisiopatologia , SRS-A/análogos & derivados , SRS-A/farmacologia , Sus scrofa , Suínos
4.
Neuroscience ; 277: 859-71, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25090924

RESUMO

Current evidence suggests that inflammation plays a role in the pathophysiology of seizures. In line with this view, selected pro-inflammatory arachidonic acid derivatives have been reported to facilitate seizures. Kainate-induced seizures are accompanied by leukotriene formation, and are reduced by inhibitors of LOX/COX pathway. Moreover, LTD4 receptor blockade and LTD4 synthesis inhibition suppress pentylenetetrazol (PTZ)-induced kindling and pilocarpine-induced recurrent seizures. Although there is convincing evidence supporting that blood-brain-barrier (BBB) dysfunction facilitates seizures, no study has investigated whether the anticonvulsant effect of montelukast is associated with its ability to maintain BBB integrity. In this study we investigated whether montelukast and other CysLT receptor antagonists decrease PTZ-induced seizures, as well as whether these antagonists preserve BBB during PTZ-induced seizures. Adult male albino Swiss mice were stereotaxically implanted with a cannula into the right lateral ventricle, and two electrodes were placed over the parietal cortex along with a ground lead positioned over the nasal sinus for electroencephalography (EEG) recording. The effects of montelukast (0.03 or 0.3 µmol/1 µL, i.c.v.), pranlukast (1 or 3 µmol/1 µL, i.c.v.), Bay u-9773 (0.3, 3 or 30 nmol/1 µL, i.c.v.), in the presence or absence of the agonist LTD4 (0.2, 2, 6 or 20 pmol/1 µL, i.c.v.), on PTZ (1.8 µmol/2 µL)-induced seizures and BBB permeability disruption were determined. The animals were injected with the antagonists, agonist or vehicle 30 min before PTZ, and monitored for additional 30 min for the appearance of seizures by electrographic and behavioral methods. BBB permeability was assessed by sodium fluorescein method and by confocal microscopy for CD45 and IgG immunoreactivity. Bay-u9973 (3 and 30 nmol), montelukast (0.03 and 0.3 µmol) and pranlukast (1 and 3 µmol), increased the latency to generalized seizures and decreased the mean amplitude of EEG recordings during seizures. LTD4 (0.2 and 2 pmol) reverted the anticonvulsant effect of montelukast (0.3 µmol). Montelukast (0.03 and 0.3 µmol) prevented PTZ-induced BBB disruption, an effect that was reversed by LTD4 at the dose of 6 pmol, but not at the doses 0.2 and 2 pmol. Moreover, the doses of LTD4 (0.2 and 2 pmol) that reverted the effect of montelukast on seizures did not alter montelukast-induced protection of BBB, dissociating BBB protection and anticonvulsant activity. Confocal microscopy analysis revealed that 1. PTZ increased the number of CD45+ and double-immunofluorescence staining for CD45 and IgG cells in the cerebral cortex, indicating BBB leakage with leukocyte infiltration; 2. while LTD4 (6 pmol) potentiated, montelukast decreased the effect of PTZ on leukocyte migration and BBB, assessed by double-immunofluorescence staining for CD45 and IgG cells in the cannulated hemisphere. Our data do not allow us ruling out that mechanisms unrelated and related to BBB protection may co-exist, resulting in decreased seizure susceptibility by montelukast. Notwithstanding, they suggest that CysLT1 receptors may be a suitable target for anticonvulsant development.


Assuntos
Anticonvulsivantes/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Antagonistas de Leucotrienos/farmacologia , Fármacos Neuroprotetores/farmacologia , Convulsões/tratamento farmacológico , Acetatos/farmacologia , Animais , Barreira Hematoencefálica/fisiopatologia , Encéfalo/fisiopatologia , Permeabilidade Capilar/efeitos dos fármacos , Permeabilidade Capilar/fisiologia , Cromonas/farmacologia , Ciclopropanos , Relação Dose-Resposta a Droga , Imunoglobulina G/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/fisiologia , Leucotrieno D4/farmacologia , Masculino , Camundongos , Pentilenotetrazol , Quinolinas/farmacologia , Receptores de Leucotrienos/agonistas , Receptores de Leucotrienos/metabolismo , SRS-A/análogos & derivados , SRS-A/farmacologia , Convulsões/fisiopatologia , Sulfetos
5.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 42(3): 253-60, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23801612

RESUMO

OBJECTIVE: To investigate the effects of CysLT receptor agonist leukotriene D4(LTD4) and antagonists on activation of microglia BV2 cells. METHODS: The expression of CysLT1 and CysLT2 protein was determined by Western blotting and immunostaining in microglia BV2 cells. BV2 cells were pretreated with or without CysLT1 receptor selective antagonist montelukast, CysLT2 receptor selective antagonist HAMI 3379, or CysLT1/CysLT2 receptor dual antagonist BAY u9773 for 30 min, then the cells were treated with LTD4 for 24 h. Cell viability was detected by MTT reduction assay. Phagocytosis and mRNA expression of IL-6 were determined by fluorescent bead tracking and RT-PCR, respectively. RESULTS: In BV2 cells, LTD4 did not affect proliferation but significantly enhanced phagocytosis and increased IL-6 mRNA expression in a concentration-dependent manner. LTD4 at 100 nmol/L induced a 1.4-fold increase of phagocytic index and a 2-fold up-regulation of IL-6 mRNA expression (P<0.01). HAMI 3379 and BAY u9773 (100 nmol/L) further increased LTD4-induced phagocytosis; BAY u9773 and montelukast decreased LTD4-induced IL-6 mRNA expression, while HAMI 3379 had no effect on that. CONCLUSION: LTD4 activates BV2 cells in vitro and enhances IL-6 mRNA expression mediated by CysLT1 receptor, LTD4 induces phagocytosis which might be negatively regulated by CysLT2 receptor in BV2 cells.


Assuntos
Leucotrieno D4/farmacologia , Microglia/citologia , Receptores de Leucotrienos/metabolismo , Acetatos/farmacologia , Linhagem Celular , Proliferação de Células , Ácidos Cicloexanocarboxílicos/farmacologia , Ciclopropanos , Humanos , Interleucina-6/metabolismo , Antagonistas de Leucotrienos/farmacologia , Microglia/metabolismo , Fagocitose , Ácidos Ftálicos/farmacologia , Quinolinas/farmacologia , SRS-A/análogos & derivados , SRS-A/farmacologia , Sulfetos
6.
J Pharmacol Exp Ther ; 339(3): 768-78, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21903747

RESUMO

Cysteinyl leukotrienes (CysLTs) are potent inflammatory mediators that predominantly exert their effects by binding to cysteinyl leukotriene receptors of the G protein-coupled receptor family. CysLT receptor 2 (CysLT(2)R), expressed in endothelial cells of some vascular beds, has been implicated in a variety of cardiovascular functions. Endothelium-specific overexpression of human CysLT(2)R in transgenic mice (hEC-CysLT(2)R) greatly increases myocardial infarction damage. Investigation of this receptor, however, has been hindered by the lack of selective pharmacological antagonists. Here, we describe the characterization of 3-(((3-carboxycyclohexyl)amino)carbonyl)-4-(3-(4-(4-phenoxybutoxy)phenyl)-propoxy)benzoic acid (BayCysLT(2)) and explore the selective effects of this compound in attenuating myocardial ischemia/reperfusion damage and vascular leakage. Using a recently developed ß-galactosidase-ß-arrestin complementation assay for CysLT(2)R activity (Mol Pharmacol 79:270-278, 2011), we determined BayCysLT(2) to be ∼20-fold more potent than the nonselective dual CysLT receptor 1 (CysLT(1)R)/CysLT(2)R antagonist 4-(((1R,2E,4E,6Z,9Z)-1-((1S)-4-carboxy-1-hydroxybutyl)-2,4,6,9-pentadecatetraen-1-yl)thio)benzoic acid (Bay-u9773) (IC(50) 274 nM versus 4.6 µM, respectively). Intracellular calcium mobilization in response to cysteinyl leukotriene administration showed that BayCysLT(2) was >500-fold more selective for CysLT(2)R compared with CysLT(1)R. Intraperitoneal injection of BayCysLT(2) in mice significantly attenuated leukotriene D(4)-induced Evans blue dye leakage in the murine ear vasculature. BayCysLT(2) administration either before or after ischemia/reperfusion attenuated the aforementioned increased myocardial infarction damage in hEC-CysLT(2)R mice. Finally, decreased neutrophil infiltration and leukocyte adhesion molecule mRNA expression were observed in mice treated with antagonist compared with untreated controls. In conclusion, we present the characterization of a potent and selective antagonist for CysLT(2)R that is useful for discerning biological activities of this receptor.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Ácidos Cicloexanocarboxílicos/farmacologia , Antagonistas de Leucotrienos/farmacologia , Leucotrieno D4/antagonistas & inibidores , Infarto do Miocárdio/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Ácidos Ftálicos/farmacologia , Receptores de Leucotrienos/metabolismo , SRS-A/análogos & derivados , Animais , Arrestinas/análise , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Orelha/irrigação sanguínea , Humanos , Camundongos , Camundongos Transgênicos , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Peroxidase/metabolismo , SRS-A/farmacologia , beta-Arrestinas , beta-Galactosidase/metabolismo
7.
Am J Respir Crit Care Med ; 184(6): 656-61, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21680952

RESUMO

RATIONALE: Biomarkers predicting development of atopic disease are needed for targeted preventive measures and to study if disease pathology may be active before onset of symptoms. OBJECTIVES: To investigate whether eosinophil protein X, leukotriene-C4/D4/E4, and 11ß-prostaglandin (PG) F2α (PGD2 metabolite) assessed in urine from healthy at-risk neonates precede development of atopic disease during the first 6 years of life. METHODS: We measured eosinophil protein X (n = 369), leukotriene-C4/D4/E4 (n = 367), and 11ß-PGF2α (n = 366) in urine from 1-month-old children participating in the Copenhagen Prospective Studies on Asthma in Childhood birth cohort. Clinical data on development of allergic sensitization, allergic rhinitis, nasal eosinophilia, blood eosinophilia, eczema, troublesome lung symptoms (significant cough or wheeze or dyspnea), and asthma were collected prospectively until age 6 years. Associations between urinary biomarkers and development of atopic traits were investigated using general estimating equations, logistic regression, and Cox regression. MEASUREMENTS AND MAIN RESULTS: Eosinophil protein X in the urine of the asymptomatic 1-month-old neonates was significantly associated with development of allergic sensitization (odds ratio, 1.49; 95% confidence interval [CI], 1.08­1.89), nasal eosinophilia (odds ratio, 3.2; 95% CI, 1.2­8.8), and eczema (hazard ratio, 1.4; 95% CI, 1.0­2.0), but not with allergic rhinitis, asthma, or blood eosinophilia. Neither leukotriene-C4/D4/E4 nor 11ß-PGF2α was associated with any of the atopic phenotypes. CONCLUSIONS: Eosinophil protein X in urine from asymptomatic neonates is a biomarker significantly associated with later development of allergic sensitization, nasal eosinophilia, and eczema during the first 6 years of life. These findings suggest activation of eosinophil granulocytes early in life before development of atopy-related symptoms.


Assuntos
Neurotoxina Derivada de Eosinófilo/urina , Hipersensibilidade Imediata/urina , Biomarcadores/urina , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Razão de Chances , Prostaglandinas/urina , SRS-A/urina
8.
Int Arch Allergy Immunol ; 155 Suppl 1: 90-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21646802

RESUMO

BACKGROUND: Little is known about the role of the cysteinyl leukotriene (cysLT) 2 receptor in the pathophysiology of asthma. The aim of this study is to investigate the effects of a cysLT1 receptor antagonist (montelukast) and a dual cysLT1/2 receptor antagonist (BAY-u9773) on airway hypersensitivity and airway inflammation induced by antigen challenge in ovalbumin (OVA)-sensitized guinea pigs. METHODS: Male Hartley guinea pigs sensitized with OVA were intraperitoneally administered 0.1, 1, or 10 mg/kg of montelukast or 0.1 mg/kg of BAY-u9773 and then challenged with inhaled OVA. Airway reactivity to acetylcholine, inflammatory cells in bronchoalveolar lavage (BAL) fluid, and eosinophil infiltration in airway walls after OVA challenge were evaluated. RESULTS: Pretreatment with 1 or 10 mg/kg, but not 0.1 mg/kg, of montelukast significantly suppressed airway hypersensitivity and eosinophil infiltration into the BAL fluid. Moreover, 0.1 mg/kg of BAY-u9773 significantly suppressed the development of these markers. The suppressive effects of BAY-u9773, although not significantly different, trended toward being greater than those of montelukast. Although all of the doses of montelukast tested and 0.1 mg/kg of BAY-u9773 significantly suppressed eosinophil infiltration in airway walls, the suppressive effect of BAY-u9773 was significantly greater than that of 0.1 mg/kg of montelukast. CONCLUSION: Signaling may contribute to the pathophysiology of asthma via the cysLT1/2 receptor.


Assuntos
Asma/tratamento farmacológico , Hiper-Reatividade Brônquica/prevenção & controle , Antagonistas de Leucotrienos/uso terapêutico , Receptores de Leucotrienos , Acetatos/farmacologia , Acetatos/uso terapêutico , Acetilcolina/farmacologia , Animais , Asma/induzido quimicamente , Asma/imunologia , Asma/patologia , Asma/fisiopatologia , Hiper-Reatividade Brônquica/fisiopatologia , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/citologia , Ciclopropanos , Eosinófilos/patologia , Cobaias , Inflamação/patologia , Inflamação/prevenção & controle , Antagonistas de Leucotrienos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Quinolinas/farmacologia , Quinolinas/uso terapêutico , SRS-A/análogos & derivados , SRS-A/farmacologia , SRS-A/uso terapêutico , Sulfetos
9.
Life Sci ; 88(17-18): 819-24, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21396378

RESUMO

AIMS: Leukotriene D(4) (LTD(4)) causes contraction of the stomach through unclear receptors. The aim of the present study is to characterize the cysteinyl leukotriene receptor (CysLT) mediating leukotriene-induced muscle contraction in the stomach. MAIN METHODS: We measured contraction of gastric muscle strips isolated from the guinea pig fundus and antrum caused by cysteinyl leukotrienes, including LTC(4), LTD(4) and LTE(4), as well as the dihydroxy leukotriene LTB(4) in vitro. KEY FINDINGS: In both fundic and antral muscle strips, LTC(4) and LTD(4) caused marked whereas LTE(4) caused moderate, concentration-dependent contractions. In contrast, LTB(4) caused only small contraction. The relative potencies for cysteinyl leukotrienes to cause contraction in both fundus and antrum were LTC(4)=LTD(4)>LTE(4). The LTD(4)-induced contraction was not affected by tetrodotoxin or atropine, suggesting that the action is not neurally mediated. The LTD(4)-induced contraction in the fundus was almost abolished by the CysLT(1) selective antagonist montelukast. In contrast, the LTD(4)-induced contraction in the antrum was only partially inhibited by montelukast or the dual CysLT(1) and CysLT(2) antagonist BAY u9773. This antral contraction was almost abolished by the combination of montelukast and BAY u9773, indicating enhancement of inhibition. SIGNIFICANCE: The results of the present study demonstrate that cysteinyl leukotrienes LTC(4), LTD(4) and LTE(4) cause moderate to marked whereas the dihydroxy leukotriene LTB(4) causes small muscle contraction in the stomach in vitro. The leukotriene-induced contraction is mediated by CysLT(1) in fundus but by CysLT(1) and CysLT(2) in antrum.


Assuntos
Fundo Gástrico/efeitos dos fármacos , Leucotrieno D4/farmacologia , Contração Muscular/efeitos dos fármacos , Antro Pilórico/efeitos dos fármacos , Receptores de Leucotrienos/fisiologia , Acetatos/farmacologia , Animais , Ciclopropanos , Relação Dose-Resposta a Droga , Fundo Gástrico/fisiologia , Cobaias , Leucotrieno C4/farmacologia , Leucotrieno E4/farmacologia , Masculino , Contração Muscular/fisiologia , Antro Pilórico/fisiologia , Quinolinas/farmacologia , Receptores de Leucotrienos/efeitos dos fármacos , SRS-A/análogos & derivados , SRS-A/farmacologia , Sulfetos
10.
Life Sci ; 88(1-2): 50-6, 2011 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-21055410

RESUMO

AIMS: We previously reported that cysteinyl leukotriene receptor 2 (CysLT(2)) mediates ischemic astrocyte injury, and leukotriene D(4)-activated CysLT(2) receptor up-regulates the water channel aquaporin 4 (AQP4). Here we investigated the mechanism underlying CysLT(2) receptor-mediated ischemic astrocyte injury induced by 4-h oxygen-glucose deprivation and 24-h recovery (OGD/R). MAIN METHODS: Primary cultures of rat astrocytes were treated by OGD/R to construct the cell injury model. AQP4 expression was inhibited by small interfering RNA (siRNA). The expressions of AQP4 and CysLTs receptors, and the MAPK signaling pathway were determined. KEY FINDINGS: OGD/R induced astrocyte injury, and increased expression of the CysLT(2) (but not CysLT(1)) receptor and AQP4. OGD/R-induced cell injury and AQP4 up-regulation were inhibited by a CysLT(2) receptor antagonist (Bay cysLT2) and a non-selective CysLT receptor antagonist (Bay u9773), but not by a CysLT(1) receptor antagonist (montelukast). Knockdown of AQP4 by siRNA attenuated OGD/R injury. Furthermore, OGD/R increased phosphorylation of ERK1/2 and p38, whose inhibitors relieved the cell injury and AQP4 up-regulation. SIGNIFICANCE: The CysLT(2) receptor mediates AQP4 up-regulation in astrocytes, and up-regulated AQP4 leads to OGD/R-induced injury, which results from activation of the ERK1/2 and p38 MAPK pathways.


Assuntos
Aquaporina 4/fisiologia , Astrócitos/enzimologia , Isquemia Encefálica/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Receptores de Leucotrienos/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Aquaporina 4/biossíntese , Astrócitos/metabolismo , Astrócitos/fisiologia , Western Blotting , Isquemia Encefálica/enzimologia , Isquemia Encefálica/fisiopatologia , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Fosforilação , Ratos , Ratos Sprague-Dawley , Receptores de Leucotrienos/efeitos dos fármacos , Receptores de Leucotrienos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SRS-A/análogos & derivados , SRS-A/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Regulação para Cima/efeitos dos fármacos
12.
Eur J Pharmacol ; 628(1-3): 195-201, 2010 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19941848

RESUMO

Many chemotherapeutic agents activate multiple signaling systems, including potentially emetogenic arachidonic acid metabolites. Of these messengers, the emetic role of the leukotriene family has been neglected. The aims of this study were to test the emetic potential of key leukotrienes (LTA(4), LTB(4), LTF(4), and the cysteinyl leukotrienes LTC(4), LTD(4) and LTE(4)), and to investigate whether the leukotriene CysLT(1) receptor antagonist pranlukast or mixed leukotriene CysLT(1/2) receptor antagonist Bay u9773 can prevent the LTC(4)-induced emesis. Least shrews were injected with varying doses of one of the six tested leukotrienes and vomiting parameters were measured for 30min. LTC(4) and LTD(4) were most efficacious, and significantly increased both the frequency and percentage of animals vomiting at doses from 0.1 and 0.05mg/kg, respectively. The other tested leukotrienes were either weakly emetic or ineffective at doses up to 4mg/kg. The relative emetogenic activities of the cysteinyl leukotrienes (LTC(4)=LTD(4)>LTE(4)) suggest that leukotriene CysLT(2) receptors have a key role in emesis. However, pranlukast dose-dependently, and at 10mg/kg completely, blocked LTC(4)-induced vomiting, implicating a leukotriene CysLT(1) receptor-mediated emetic effect. Bay u9773 dose-dependently reduced the percentage of animals vomiting, but did not significantly reduce vomiting frequency. Fos immunoreactivity, measured subsequent to LTC(4)-induced vomiting to define its putative anatomical substrates, was significantly increased in the enteric nervous system and medullary dorsal vagal complex following LTC(4) (P<0.05) versus vehicle injections. This study is the first to show that some leukotrienes induce emesis, possibly involving both central and peripheral leukotriene CysLT(1) and/or leukotriene CysLT(2) receptors.


Assuntos
Cromonas/farmacologia , Cisteína/efeitos adversos , Leucotrienos/efeitos adversos , Vômito/induzido quimicamente , Vômito/tratamento farmacológico , Animais , Cromonas/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Imuno-Histoquímica , Injeções , Leucotrieno C4/administração & dosagem , Leucotrieno C4/efeitos adversos , Masculino , Proteínas Proto-Oncogênicas c-fos/metabolismo , SRS-A/análogos & derivados , SRS-A/farmacologia , Vômito/metabolismo
13.
Alerg. inmunol. clin ; 28(3/4): 54-56, 2010. graf
Artigo em Espanhol | LILACS | ID: lil-616801

RESUMO

La denominación anafiláctica u anafilactoide, tienen que ver con el mecanismo de producción que, podrá ser distinto en relación a la causa desencadenante, no lo es, sin embargo, si se consideran las células implicadas, los mediadores involucrados, las expresiones clínicas y, sobre todos, su manejo. Es por eso que se reporduce dos cuadros sintéticos que abordan la temática.


Assuntos
Humanos , Masculino , Feminino , Alergia e Imunologia , SRS-A
14.
Vascul Pharmacol ; 50(5-6): 171-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19563734

RESUMO

The purpose of the present study is to identify whether interleukin (IL)-18 can modulate cysteinyl leukotriene 2 receptor (CysLT2R) expression in Human Umbilical Vein Endothelial Cells (HUVECs) and how it influences the cell death. According to the results from real-time reverse transcription PCR, confocal laser scanning microscopy, and western blotting, a dose-dependent augmentation of CysLT2R protein expression in HUVECs was triggered by IL-18 for the first 2 h followed by down-regulation within the next 22 h after IL-18 administration. The flow cytometry showed that non-selective CysLT1R and CysLT2R antagonist BAY-u9773 could attenuate the early stage apoptosis mediated by IL-18 whereas CysLT1R antagonist Montelukast couldn't. Also, pretreatment with BAY-u9773 suppressed calcium influx of HUVECs induced by IL-18 whereas Montelukast didn't work. The observation that progression of cell death aggravated by IL-18 could be attenuated by BAY-u9773 may offer a chance to develop a novel way to treat arteriosclerosis.


Assuntos
Apoptose/fisiologia , Células Endoteliais/patologia , Interleucina-18/fisiologia , Receptores de Leucotrienos/biossíntese , Veias Umbilicais/fisiopatologia , Regulação para Cima/efeitos dos fármacos , Acetatos/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Ciclopropanos , Células Endoteliais/efeitos dos fármacos , Feminino , Humanos , Antagonistas de Leucotrienos/farmacologia , Quinolinas/farmacologia , SRS-A/análogos & derivados , SRS-A/farmacologia , Sulfetos , Fatores de Tempo
15.
Tohoku J Exp Med ; 217(3): 185-91, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19282653

RESUMO

The cysteinyl leukotrienes (LTs), LTC(4), LTD(4), and LTE(4), are potent inflammatory mediators and are involved in allergic reactions, such as bronchoconstriction, eosinophilic inflammation, and allergic cell proliferation. The present study aimed to elucidate the role of constitutively produced cysteinyl LTs in mast cell activation. We used a newly developed quantification method based on mass spectrometry to detect cysteinyl LTs in the cultured medium of mouse bone marrow-derived mast cells (BMMCs), which were obtained by interleukin (IL)-3-conditioned culture of mouse bone marrow. BMMCs were stimulated with immunoglobulin (Ig) E and antigen (IgE/Ag) or lipopolysaccharide for 1 or 24 h. This new quantification method revealed that unstimulated BMMCs produced and secreted LTB4 and LTE4 after 24 h of incubation. The treatment of unstimulated BMMCs for 2 h with montelukast, an antagonist of a cysteinyl LT receptor, CysLT1, resulted in the suppression of a downstream signaling event of this receptor, i.e., the decrease in phosphorylation of extracellular responsive kinases. Thus, cysteinyl LTs constitutively simulate BMMCs through the CysLT1 receptor in an autocrine manner. Treatment of BMMCs for 3 weeks with montelukast, which caused long-term inhibition of the autocrine cyteinyl LT-derived signal, significantly attenuated the IgE/Ag-dependent degranulation, as judged by the decrease in the release of beta-hexosaminidase, an enzyme contained in the granules, whereas the production of cytokines, such as IL-6 and tumor necrosis factor-alpha, were largely unaffected. In conclusion, an autocrine signal derived from constitutively produced cysteinyl LTs predisposes mast cells to the degranulation upon allergic stimulation.


Assuntos
Comunicação Autócrina/fisiologia , Células da Medula Óssea/fisiologia , Degranulação Celular/fisiologia , Mastócitos/fisiologia , SRS-A/metabolismo , Acetatos , Animais , Células da Medula Óssea/metabolismo , Cromatografia Líquida , Ciclopropanos , Mastócitos/metabolismo , Camundongos , Quinolinas , Sulfetos , Espectrometria de Massas em Tandem
16.
J Pharmacol Sci ; 109(2): 285-92, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19234368

RESUMO

The actions of cysteinyl leukotrienes (CysLTs) are mediated by activating CysLT receptors, CysLT(1), and CysLT(2). The CysLT(1) receptor mediates vascular responses to CysLTs; however, its effect on the proliferation and migration of endothelial cells is not clarified. To determine this effect, we observed proliferation and migration in EA.hy926 cells, a human endothelial cell line, and the involvement of activation of mitogen-activated protein kinases (MAPKs). We found that LTD(4) did not affect the proliferation, but significantly stimulated the migration of endothelial cells. LTD(4) also induced the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, but not those of p38 or JNK. The LTD(4)-induced migration and ERK1/2 phosphorylation were blocked by the CysLT(1)-receptor antagonist montelukast and the dual antagonist Bay u9773, but not by the CysLT(2)-receptor antagonist Bay cysLT2; the migration was also inhibited by the ERK1/2 inhibitor U0126. Our findings indicate that LTD(4) stimulates the CysLT(1) receptor-mediated migration of endothelial cells; this may be regulated by the ERK1/2 pathway.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Leucotrieno D4/farmacologia , Receptores de Leucotrienos/efeitos dos fármacos , Acetatos/farmacologia , Butadienos/farmacologia , Linhagem Celular , Ciclopropanos , Células Endoteliais/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Antagonistas de Leucotrienos/farmacologia , Nitrilas/farmacologia , Quinolinas/farmacologia , SRS-A/análogos & derivados , SRS-A/farmacologia , Sulfetos
17.
Chest ; 135(5): 1142-1149, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19118273

RESUMO

INTRODUCTION: The abundant expression of leukotrienes (LTs) and their receptors in adenotonsillar tissues of children with obstructive sleep apnea (OSA) suggest that LT antagonists could be useful in treating OSA. METHODS: The effects of LTD4 and of LT receptor antagonists zileuton, montelukast, and BAY u9773 were examined on mixed cell cultures prepared from dissociated tonsils or adenoids harvested intraoperatively from children with polysomnographically diagnosed OSA. Proliferation was assessed by (3)[H]-thymidine incorporation, and inflammatory cytokine production (tumor necrosis factor [TNF]-alpha, interleukin [IL]-6, IL-8, IL-10, and IL-12) was assessed in supernatants using enzyme-linked immunosorbent assay. RESULTS: LTD4 elicited dose-dependent increases in adenotonsillar cell proliferation (p < 0.001; n = 12). All LT antagonists exhibited dose-dependent reductions in adenotonsillar cellular proliferation rates, with montelukast more than BAY u9773 more than zileuton (n = 14/group; p < 0.001). However, BAY u9773 showed partial agonist effects and increased cellular proliferation at higher concentrations (10(-4) mmol/L; p < 0.01; n = 12). LTD4 effects were partially blocked by montelukast and BAY u9773 but not by zileuton. All three antagonists reduced TNF-alpha, IL-6, and IL-12 concentrations, with selective changes in IL-8 and no effects on IL-10 levels. CONCLUSIONS: LT pathways mediate intrinsic proliferative and inflammatory signaling pathways in adenotonsillar tissues from children with OSA, and targeted pharmacologic disruption of these pathways may provide nonsurgical alternatives for prevention and treatment of this disease.


Assuntos
Tonsila Faríngea/citologia , Antagonistas de Leucotrienos/farmacologia , Tonsila Palatina/citologia , Apneia Obstrutiva do Sono/metabolismo , Acetatos/farmacologia , Acetatos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Criança , Pré-Escolar , Ciclopropanos , Relação Dose-Resposta a Droga , Humanos , Hidroxiureia/análogos & derivados , Hidroxiureia/farmacologia , Hidroxiureia/uso terapêutico , Imuno-Histoquímica , Interleucinas/análise , Antagonistas de Leucotrienos/uso terapêutico , Leucotrieno D4/farmacologia , Polissonografia , Quinolinas/farmacologia , Quinolinas/uso terapêutico , SRS-A/análogos & derivados , SRS-A/farmacologia , SRS-A/uso terapêutico , Apneia Obstrutiva do Sono/tratamento farmacológico , Sulfetos
18.
Alerg. inmunol. clin ; 27(3/4): 3-4, 2009.
Artigo em Espanhol | LILACS | ID: lil-614166

RESUMO

El tratameinto apropiado deberá instituirse tan rápido como sea posible.


Assuntos
Humanos , Masculino , Feminino , SRS-A
19.
FASEB J ; 22(12): 4352-62, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18779380

RESUMO

Cysteinyl leukotrienes (CysLTs) are potent mediators of inflammation synthesized by the concerted actions of 5-lipoxygenase (5-LO), 5-LO-activating protein (FLAP), leukotriene C(4) synthase, and additional downstream enzymes, starting with arachidonic acid substrate. CysLTs produced by macrophages, eosinophils, mast cells, and other inflammatory cells activate 3 different high-affinity CysLT receptors: CysLT(1)R, CysLT(2)R, and GPR 17. We sought to investigate vascular sites of CysLT(2)R expression and the role and mechanism of this receptor in mediating vascular permeability events. Vascular expression of CysLT(2)R was investigated by reporter gene expression in a novel CysLT(2)R deficient-LacZ mouse model. CysLT(2)R was expressed in small, but not large, vessels in mouse brain, bladder, skin, and cremaster muscle. Intravital, in addition to confocal and electron, microscopy investigations using FITC-labeled albumin in cremaster postcapillary venule preparations indicated rapid CysLT-mediated permeability, which was blocked by application of BAY-u9773, a dual CysLT(1)R/CysLT(2)R antagonist or by CysLT(2)R deficiency. Endothelial human CysLT(2)R overexpression in mice exacerbated vascular leakage even in the absence of exogenous ligand. The enhanced vascular permeability mediated by CysLT(2)R takes place via a transendothelial vesicle transport mechanism as opposed to a paracellular route and is controlled via Ca(2+) signaling. Our results reveal that CysLT(2)R can mediate inflammatory reactions in a vascular bed-specific manner by altering transendothelial vesicle transport-based vascular permeability.


Assuntos
Transporte Biológico/fisiologia , Permeabilidade Capilar/fisiologia , Receptores de Leucotrienos/fisiologia , Animais , Transporte Biológico/genética , Sinalização do Cálcio/fisiologia , Permeabilidade Capilar/genética , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Fluoresceína-5-Isotiocianato/análogos & derivados , Expressão Gênica , Humanos , Microdomínios da Membrana/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Receptores de Leucotrienos/biossíntese , SRS-A/análogos & derivados , SRS-A/farmacologia , Albumina Sérica
20.
Neurogastroenterol Motil ; 20(10): 1140-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18651869

RESUMO

Leucotriene D(4) (LTD(4)) causes contraction of the guinea-pig and cat oesophagus. Effects of cysteinyl leucotrienes in the human oesophagus were unknown. To investigate and compare the cysteinyl leucotriene effects in the human oesophagus with those in the guinea-pig oesophagus, we measured contraction of muscularis mucosae strips isolated from the human and guinea-pig oesophagus caused by cysteinyl leucotrienes, LTC(4), LTD(4) and LTE(4), as well as the dihydroxy leucotriene, LTB(4). Effects of leucotrienes in human were similar to those in guinea-pig oesophagus. LTC(4) and LTD(4) caused moderate, whereas LTE(4) caused mild, concentration-dependent contraction. LTE(4) was a partial agonist. In contrast, LTB(4) did not cause any contraction. The relative potencies for cysteinyl leucotrienes to cause contraction were LTD(4) = LTC(4) > LTE(4). The LTD(4)-induced contraction was moderately inhibited by two selective CysLT(1) receptor antagonists, montelukast and zafirlukast, in both human and guinea-pig oesophagus. In addition, the LTD(4)-induced contraction was not and only slightly inhibited by BAY u9773, the CysLT(1) and CysLT(2) receptor antagonist, in the human and guinea-pig oesophageal muscularis mucosae respectively. These indicate the existence of the CysLT(1) mediating oesophageal contraction in both human and guinea-pig oesophagus. The LTD(4)-induced contraction was not affected by tetrodotoxin, atropine or capsaicin, suggesting a direct effect. These results demonstrate that cysteinyl leucotrienes but not the dihydroxy leucotriene cause contraction in the human and guinea-pig oesophagus. CysLT(1) mediates contraction in both human and guinea-pig oesophagus.


Assuntos
Esôfago/fisiologia , Leucotrienos/metabolismo , Contração Muscular/fisiologia , Receptores de Leucotrienos/metabolismo , Acetatos/farmacologia , Animais , Atropina/farmacologia , Capsaicina/farmacologia , Carbacol/farmacologia , Agonistas Colinérgicos/farmacologia , Ciclopropanos , Esôfago/anatomia & histologia , Esôfago/efeitos dos fármacos , Cobaias , Humanos , Indóis , Antagonistas de Leucotrienos/farmacologia , Masculino , Antagonistas Muscarínicos/farmacologia , Contração Muscular/efeitos dos fármacos , Fenilcarbamatos , Quinolinas/farmacologia , Receptores de Leucotrienos/genética , SRS-A/análogos & derivados , SRS-A/farmacologia , Fármacos do Sistema Sensorial/farmacologia , Bloqueadores dos Canais de Sódio/farmacologia , Sulfetos , Sulfonamidas , Tetrodotoxina/farmacologia , Compostos de Tosil/farmacologia
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