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1.
Curr Drug Metab ; 10(3): 256-71, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19442088

RESUMO

Flavonoids are a large class of naturally occurring compounds widely present in fruits, vegetables, and beverages derived from plants. Reports have suggested that these compounds might be useful for the prevention of a number of diseases, partly due to their anti-inflammatory properties. It has been demonstrated that flavonoids are able to inhibit expression of isoforms of inducible nitric oxide synthase, ciclooxygenase and lipooxygenase, which are responsible for the production of a great amount of nitric oxide, prostanoids and leukotrienes, as well as other mediators of the inflammatory process such as cytokines, chemokines or adhesion molecules. Modulation of the cascade of molecular events leading to the over-expression of those mediators include inhibition of transcription factors such as nuclear factor kappa B, activator protein 1, signal transducers and activators of transcription, CCAAT/enhancer binding protein and others. Effects on the binding capacity of transcription factors may be regulated through the inhibition of protein kinases involved in signal transduction, such as mitogen activated protein kinases. Although the numerous studies published with in vitro approaches allow identifying molecular mechanisms of flavonoid effects, the limited bioavailability of these molecules makes necessary validation in humans. Whatever the case, the data available make clear the potential utility of dietary flavonoids or new flavonoid-based agents for the possible treatment of inflammatory diseases. The present review summarizes recent research data focusing on the modulation of the expression of different inflammatory mediators by flavonoids and the effects on cell signaling pathways responsible for their anti-inflammatory activity.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Ciclo-Oxigenase 2/fisiologia , Citocinas/fisiologia , Humanos , Proteínas Quinases Ativadas por Mitógeno/fisiologia , NF-kappa B/fisiologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/fisiologia
2.
Mini Rev Med Chem ; 8(14): 1485-93, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19075806

RESUMO

Dysregulation of apoptosis is a major contributor to the initiation and aggravation of liver injury. Agents that modulate apoptosis may be of therapeutic benefit in a number of liver diseases, and research related to cell type-specific activation or inhibition of apoptotic signaling pathways will provide new strategies for treatment.


Assuntos
Apoptose/efeitos dos fármacos , Hepatopatias/tratamento farmacológico , Hepatopatias/patologia , Transdução de Sinais/efeitos dos fármacos , Animais , Atorvastatina , Gliotoxina/farmacologia , Ácidos Heptanoicos/farmacologia , Humanos , Hepatopatias/fisiopatologia , Hepatopatias/virologia , Conformação Molecular , Pirróis/farmacologia , Ácido Ursodesoxicólico/química , Ácido Ursodesoxicólico/farmacologia
3.
J Laryngol Otol ; 132(6): 554-559, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29888688

RESUMO

OBJECTIVE: To evaluate the presence of endolymphatic hydrops in patients with immune-mediated inner-ear disease. METHODS: The presence of endolymphatic hydrops was prospectively evaluated in 17 patients clinically diagnosed with secondary (n = 5) or primary (n = 12) immune-mediated inner-ear disease, who attended the ENT department of a tertiary care centre for evaluation or treatment over the previous year. All patients underwent magnetic resonance imaging of the temporal bone. RESULTS: Intratympanic gadolinium three-dimensional magnetic resonance imaging diagnosed hydrops in 11 of 12 patients with primary immune-mediated inner-ear disease (92 per cent). Of these, seven patients (64 per cent) presented only cochlear (n = 5) or predominantly cochlear (n = 2) hydrops. A positive magnetic resonance imaging result was observed in only one of five patients with secondary immune-mediated inner-ear disease (20 per cent). CONCLUSION: This study confirms the presence of endolymphatic hydrops in immune-mediated inner-ear disease patients. The virtual absence of hydrops in patients with secondary immune-mediated inner-ear disease is remarkable, although firm conclusions cannot be drawn; this should be explored in a multicentre study with a larger sample of patients. A different immune reaction without development of endolymphatic hydrops should not be ruled out in secondary immune-mediated inner-ear disease patients.


Assuntos
Doenças Autoimunes/diagnóstico por imagem , Hidropisia Endolinfática/diagnóstico por imagem , Doenças do Labirinto/diagnóstico por imagem , Adolescente , Adulto , Idoso , Audiometria de Tons Puros , Doenças Autoimunes/fisiopatologia , Meios de Contraste , Hidropisia Endolinfática/fisiopatologia , Feminino , Compostos Heterocíclicos , Humanos , Imageamento Tridimensional , Injeção Intratimpânica , Doenças do Labirinto/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos , Estudos Prospectivos , Adulto Jovem
4.
Nutr Hosp ; 22(3): 287-93, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17612370

RESUMO

Flavonoids are a group of natural substances that are located in sources of vegetal origin. More than 4,000 varieties of flavonoids have been identified. All of them are phenyl-benzopyrones of low molecular weight with a basic structure formed by two benzene rings united through a heterocyclic pyrane or pyrone. Besides their relevance in plants, flavonoids are important for human health. Their antioxidant capacity confers a therapeutic potential in cardiovascular diseases, gastric or duodenal ulcers, cancer or hepatic pathologies. Also important are their antiviral and anti-allergic actions, as well as their anti-thrombotic and anti-inflammatory properties. Prostaglandins and nitric oxide biosynthesis is involved in inflammation, and isoforms of inducible nitric oxide synthase (iNOS) and of cyclooxygenase (COX-2) are responsible for the production of a great amount of these mediators. It has been demonstrated that flavonoids are able to inhibit both enzymes, as well as other mediators of the inflammatory process such as reactive C protein or adhesion molecules. Modulation of the cascade of molecular events leading to the overexpression of those mediators include inhibition of transcription factors such as nuclear factor kappa B and AP-1, through the inhibition of protein kinases involved in signal transduction. Increased antioxidant defenses through activation of the NF-E2 related factor 2 (Nrf2) also contribute to the anti-inflammatory capacity of flavonoids.


Assuntos
Anti-Inflamatórios/uso terapêutico , Dieta , Flavonoides/uso terapêutico , Inflamação/tratamento farmacológico , Animais , Humanos
5.
Nutr Hosp ; 22(2): 199-209, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17416036

RESUMO

Fulminant hepatic failure (FHF) is a very serious clinical sindrome that, in spite of the important therapeutical advances that have taken place in the last years by means of bioartifical hepatic support devices and hepatic transplantation, is still associated to a high mortality. Knowledge and treatment of the FHF have been limited by the lack of satisfactory animal models. Among the attempts to develop a suitable model are surgical models, such as hepatectomy and total and/or partial devascularization, or the use of chemical substances with hepatic toxicity, such as acetaminophen, azoximethane, galactosamine or thioacetamide, among others. However, most of these models do not adequatly reflect the pattern of the human disease and all of them present important limitations. Although viral hepatitis is one of the most frequent causes of FHF, the use of viral agents to develop animal models has been little and unfortunate. Our group has recently developed a viral animal model of FHF by means of the inoculation of rabbits with the virus of the rabbit hemorrhagic disease. This model displays biochemical, and histological characteristics, and clinical signs that ressemble those in human FHF. In the present article, the most widely used animal models of FHF, together with their main advantages and disadvantages, are presented.


Assuntos
Modelos Animais de Doenças , Falência Hepática Aguda , Animais , Humanos , Falência Hepática Aguda/etiologia
6.
Nutr Hosp ; 33(2): 92, 2016 Mar 25.
Artigo em Espanhol | MEDLINE | ID: mdl-27238775

RESUMO

Introducción: la insuficiencia hepática fulminante (IHF) es un síndrome clínico poco frecuente, que se caracteriza por una disfunción hepática severa y repentina. La tioacetamida (TAA) es una hepatotoxina cuya administración puede inducir necrosis centrolobulillar en las células hepáticas y aumentar la formación de especies reactivas de oxígeno y la peroxidación lipídica en ratas. La glutamina es un precursor para la síntesis de glutatión. Objetivo: el objetivo del estudio es evaluar los efectos antioxidantes de la glutamina en un modelo de rata de IHF inducida por TAA. Métodos: ratas macho Wistar se dividieron en cuatro grupos de acuerdo con el tratamiento y el tiempo de evaluación: control, glutamina (25 mg/kg), tioacetamida (400 mg/kg) y tioacetamida más glutamina. Los animales se evaluaron después de 24, 36 y 48 horas. Se recogieron muestras de sangre para el análisis de los niveles de aspartato aminotransferasa (AST), alanina aminotransferasa (ALT), fosfatasa alcalina (AP), bilirrubina total (TB) y creatinina (CRE), y muestras de hígado para evaluar la peroxidación lipídica, las sustancias reactivas al ácido tiobarbitúrico (TBARS), la actividad de las enzimas antioxidantes superóxido dismutasa (SOD), glutatión peroxidasa (GPx), catalasa (CAT) y glutatión S-transferasa (GST). Además se midieron mediante inmunohistoquímica el factor nuclear kappa N (NF-κB), el fator de necrosis tumoral (TNF-α) y la óxido nítrico sintasa inducible (iNOS). Resultados: la TAA causó alteraciones en los parámetros bioquímicos e histológicos, y el aumento de los marcadores del proceso inflamatorio. Los niveles de TBARS y la actividad de SOD y GST fueron significativamente inferiores en los grupos de glutamina en comparación con TAA. La actividad de CAT se incrementó en los animales tratados con glutamina en comparación con la TAA. La actividad GPx también fue menor a las 36 y 48 h en los animales tratados com glutamina. El daño tisular y la expresión de NF-κB, TNF-α e iNOS fueron significativamente inferiores en los animales tratados con glutamina. Conclusión: la glutamina ha demostrado tener efectos protectores contra el daño hepático en un modelo de IHF inducida por TAA en la rata.


Assuntos
Antioxidantes/farmacologia , Glutamina/farmacologia , Inflamação/tratamento farmacológico , Falência Hepática Aguda/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Animais , Inflamação/etiologia , Estimativa de Kaplan-Meier , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/complicações , Masculino , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Tioacetamida
7.
Oncotarget ; 6(1): 368-80, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25621889

RESUMO

Hypermethylation of tumor suppressor genes is one of the hallmarks in the progression of brain tumors. Our objectives were to analyze the presence of the hypermethylation of EPB41L3, RASSF2 and TSP-1 genes in 132 diffuse gliomas (astrocytic and oligodendroglial tumors) and in 10 cases of normal brain, and to establish their association with the patients' clinicopathological characteristics. Gene hypermethylation was analyzed by methylation-specific-PCR and confirmed by pyrosequencing (for EPB41L3 and TSP-1) and bisulfite-sequencing (for RASSF2). EPB41L3, RASSF2 and TSP-1 genes were hypermethylated only in tumors (29%, 10.6%, and 50%, respectively), confirming their cancer-specific role. Treatment of cells with the DNA-demethylating-agent 5-aza-2'-deoxycytidine restores their transcription, as confirmed by quantitative-reverse-transcription-PCR and immunofluorescence. Immunohistochemistry for EPB41L3, RASSF2 and TSP-1 was performed to analyze protein expression; p53, ki-67, and CD31 expression and 1p/19q co-deletion were considered to better characterize the tumors. EPB41L3 and TSP-1 hypermethylation was associated with worse (p = 0.047) and better (p = 0.037) prognosis, respectively. This observation was confirmed after adjusting the results for age and tumor grade, the role of TSP-1 being most pronounced in oligodendrogliomas (p = 0.001). We conclude that EPB41L3, RASSF2 and TSP-1 genes are involved in the pathogenesis of diffuse gliomas, and that EPB41L3 and TSP-1 hypermethylation are of prognostic significance.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Proteínas dos Microfilamentos/genética , Trombospondina 1/genética , Proteínas Supressoras de Tumor/genética , Idoso , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/mortalidade , Metilação de DNA/genética , Intervalo Livre de Doença , Feminino , Imunofluorescência , Glioma/mortalidade , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Free Radic Biol Med ; 30(8): 836-45, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11295526

RESUMO

Free radicals are involved in aging and cyclosporin A-induced toxicity. The age-related changes in the liver oxidative status of glutathione, lipid peroxidation, and the activity of the enzymatic antioxidant defense system, as well as the influence of aging on the susceptibility to the hepatotoxic effects of cyclosporin (CyA) were investigated in rats of different ages (1, 2, 4, and 24 months). The hepatic content of reduced glutathione (GSH) increased with aging, peaked at 4 months, and decreased in senescent rats. By contrast, glutathione disulfide (GSSG) and thiobarbituric acid-reactive substances (TBARS) concentrations and superoxide dismutase, catalase, and glutathione peroxidase activities were higher in the oldest than in the youngest rats. CyA treatment, besides inducing the well-known cholestatic syndrome, increased liver GSSG and TBARS contents and the GSSG/GSH molar ratio, and altered the nonenzymatic and enzymatic antioxidant defense systems. The CyA-induced cholestasis and hepatic depletion of GSH, and the increases in the GSSG/GSH ratio, and in GSSG and TBARS concentrations were higher in the older than the mature rats. Moreover, superoxide dismutase and catalase activities were found to be significantly decreased only in treated senescent rats. The higher CyA-induced oxidative stress, lipoperoxidation, and decreases in the antioxidant defense systems in the aged animals render them more susceptible to the hepatotoxic effects of cyclosporin.


Assuntos
Envelhecimento/fisiologia , Antioxidantes/metabolismo , Ciclosporina/toxicidade , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Animais , Ácidos e Sais Biliares/sangue , Bilirrubina/sangue , Catalase/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Fígado/fisiopatologia , Masculino , Oxirredução/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Transaminases/sangue
9.
Eur J Cancer ; 35(2): 320-4, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10448278

RESUMO

The use of bioreductive agents in enzyme-directed bioreductive therapy has been proposed to take advantage not only of hypoxia in tumours, but also of the presence of reductases that metabolise such compounds. In this study, we studied the activities of NADPH cytochrome P450 reductase (P450R) and carbonyl reductase (CR) in 17 human lung tumours and 18 human breast tumours, together with the corresponding normal tissues. For lung cancer but not for breast cancer there was a significant difference in the CR activity between normal and tumour tissue. CR activity was increased with respect to the normal tissue between 2-fold and 40-fold indicating heterogeneity in tumour samples. No relationship was found between CR activity and the histological type, tumoral grade or TNM stage of the tumours. Although some variation in P450R activity in tumoral versus normal tissues was found in the majority of the samples studied, no significant differences could be demonstrated.


Assuntos
Oxirredutases do Álcool/metabolismo , Neoplasias da Mama/enzimologia , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Neoplasias Pulmonares/enzimologia , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Proteínas de Neoplasias/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino
10.
Transplantation ; 66(1): 84-8, 1998 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9679826

RESUMO

BACKGROUND: Tacrolimus (FK506) is an immunosuppressive agent used for the prevention of allograft rejection after organ transplantation. The aim of this study was to investigate the effects of chronic tacrolimus treatment on bile secretion in rats. METHODS: Tacrolimus was administered intraperitoneally at doses of 0.2, 0.5, and 0.8 mg/kg/day for 6 weeks. RESULTS: Bile flow was significantly reduced at doses of 0.5 mg/kg and 0.8 mg/kg (-25% and -32%, respectively). Bile acid secretion was not significantly modified, but bicarbonate secretion decreased at doses of 0.5 mg/kg and 0.8 mg/kg (-23% and -29%, respectively). Glutathione secretion was significantly reduced at doses of 0.5 mg/kg (-29%) and 0.8 mg/kg (-49%). Liver glutathione concentration was reduced at the higher dose (-17%). Liver gamma-glutamyl-cysteinyl synthetase activity was elevated (+22%, +10, and +15%) and gamma-glutamyl transpeptidase activity was reduced (-18%, -40%, and -25%) at all doses. Dichlorofluorescein and thiobarbituric acid-reactive substance concentrations were not significantly modified. Liver glutathione peroxidase activity increased at doses of 0.5 mg/kg (+65%) and 0.8 mg/kg (+56%). Kidney concentration of thiobarbituric acid-reactive substances was significantly increased at doses of 0.5 mg/kg (+17%) and 0.8 mg/kg (+12%). CONCLUSIONS: Our data indicate that tacrolimus at high doses induces cholestasis by inhibiting primarily biliary excretion of glutathione and, to a lesser extent, bicarbonate. The decrease in biliary glutathione secretion is not due to a lower synthesis or degradation and could be related to its increased sinusoidal efflux.


Assuntos
Colestase/induzido quimicamente , Glutationa/metabolismo , Imunossupressores/farmacologia , Tacrolimo/farmacologia , Animais , Bile/química , Bile/efeitos dos fármacos , Bile/fisiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar
11.
Life Sci ; 73(26): 3387-97, 2003 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-14572880

RESUMO

The aim of this study was to investigate the effects of cyclosporin (CyA) treatment on biliary glutathione efflux in rats of different ages (1, 2, 4, and 24 months). CyA treatment reduced the liver content of total glutathione in 1-, 2- and 24 month old rats (-30%, -43% and -30%, respectively). By contrast, oxidized glutathione (GSSG) concentration in liver tended to increase, although non significantly, in the rats aged 4 and 24 month (+36% and +28%, respectively). The oxidized-to-reduced glutathione ratio was significantly increased in 2-, 4- and 24 month old animals (+23%, +36% and >100%, respectively). Regarding biliary glutathione, our data indicate that efflux rates of total glutathione in control (untreated) rats increased to a maximum at 4 months, and decreased (-56%) in 24 month old rats, although values were still higher than those from young animals. CyA treatment significantly reduced biliary glutathione secretion except in 24 month old rats (-98%, -66% and -32%, at 1, 2 and 4 month, respectively). In addition, following inhibition of the intrabiliary catabolism of the tripeptide by acivicin, glutathione efflux rates into bile were significantly reduced by the drug only in 1- and 2 month old rats (-29% and -55%, respectively) and even tended to increase, although non significantly, in oldest animals. Our data indicate that inhibition of biliary glutathione efflux by CyA was greater in younger rats and support the view that increased intrabiliary catabolism of the tripeptide and inhibition of its canalicular transport could contribute to the decline in biliary glutathione secretion induced by the drug.


Assuntos
Envelhecimento/fisiologia , Sistema Biliar/efeitos dos fármacos , Ciclosporina/toxicidade , Glutationa/metabolismo , Imunossupressores/toxicidade , Fígado/efeitos dos fármacos , Animais , Sistema Biliar/metabolismo , Ciclosporina/administração & dosagem , Dissulfeto de Glutationa/metabolismo , Imunossupressores/administração & dosagem , Injeções Intraperitoneais , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar
12.
Life Sci ; 63(22): 1963-74, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9839540

RESUMO

The purpose of this investigation was to determine the effects of experimental dicrocoeliosis on bile formation in the hamster. Studies were carried out at 120 days after infection with an oral dose of 40 metacercariae of Dicrocoelium dendriticum. A significant elevation in bile flow (+20%) and in the biliary output of glutathione (+34%), bile acid (+59%), cholesterol (+108%), phospholipids (+99%) and alkaline phosphatase (+36%) was observed in the infected animals. The bile-to-plasma [14C] mannitol ratio increased to values greater than 1 and there was a reduced contribution (-26%) of biliary tree to bile formation. Those data suggest that enhancement in choleresis had a canalicular origin. The presence of oxidative stress, evidenced by the increased oxidized/reduced glutathione ratio and TBARS concentrations, may contribute to the elevated glutathione efflux into bile. Enhancement in bile acid output was not due to qualitative or quantitative changes in bile acid metabolism, as indicated by the absence of significant modification in liver cholesterol 7alpha-hydroxylase activity and bile acid profile in bile. Increase in the ability of the canalicular membrane to export bile acids was not involved, since maximal secretion rate for exogenously administered taurocholate was decreased. When bile flow, bile acid and biliary lipid secretion was determined in colchicine-pretreated animals differences between control and infected animals were abolished, suggesting that stimulation of the transcytotic vesicle pathway plays an important role in the alteration of the biliary function caused by dicrocoeliosis.


Assuntos
Bile/metabolismo , Dicrocelíase/fisiopatologia , Fosfatase Alcalina/metabolismo , Animais , Bile/fisiologia , Ácidos e Sais Biliares/metabolismo , Ductos Biliares/parasitologia , Colesterol/metabolismo , Cricetinae , Dicrocelíase/parasitologia , Fezes/química , Fezes/parasitologia , Glutationa/metabolismo , Metabolismo dos Lipídeos , Masculino , Mesocricetus , Fosfolipídeos/metabolismo
13.
Life Sci ; 75(6): 717-32, 2004 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-15172180

RESUMO

Bile duct ligation (BDL) in rats induces portal fibrosis. This process has been linked to changes in the oxidative state of the hepatic cells and in the production of nitric oxide. Our objective was to find possible temporal connections between hepatic redox state, NO synthesis and liver injury. In this work we have characterized hepatic lesions 17 and 31 days after BDL and determined changes in hepatic function, oxidative state, and NO production. We have also analyzed the expression and localization of inducible NO synthase (NOS2) and constitutive NO synthase (NOS3). After 17 and 31 days from ligature, lipid peroxidation is increased and both plasma concentration and biliary excretion of nitrite+nitrate are rised. 17 days after BDL both NOS2 and NOS3 are expressed intensely and in the same regions. 31 days after BDL, the expression of NOS2 remains elevated and is localized mostly in preserved hepatocytes in portal areas and in neighborhoods of centrolobulillar vein. NOS3 is localized in vascular regions of portal spaces and centrolobulillar veins and in preserved sinusoids and although its expression is greater than in control animals (34%), it is clearly lower (50%) than 17 days after BDL. The time after BDL is crucial in the study of NO production, intrahepatic localization of NOS isoforms expression, and cell type involved, since all these parameters change with time. BDL-induced, peroxidation and fibrosis are not ligated by a cause-effect relationship, but rather they both seem to be the consequence of common inductors.


Assuntos
Ductos Biliares Extra-Hepáticos/cirurgia , Peroxidação de Lipídeos/fisiologia , Cirrose Hepática Experimental/enzimologia , Fígado/enzimologia , Óxido Nítrico Sintase/metabolismo , Animais , Pressão Sanguínea/fisiologia , Western Blotting , Modelos Animais de Doenças , Hidroxiprolina/análise , Hidroxiprolina/metabolismo , Técnicas Imunoenzimáticas , Fígado/química , Cirrose Hepática Experimental/etiologia , Cirrose Hepática Experimental/patologia , Masculino , Nitratos/metabolismo , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Nitritos/metabolismo , Estresse Oxidativo , Ratos , Ratos Wistar
14.
Nutrition ; 16(2): 125-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10696636

RESUMO

Our aim was to determine the effects of glutamine or alanyl glutamine parenteral supplementation on the liver oxidant/antioxidant balance and on cytochrome-P450-mediated detoxication in rats. Animals were infused for 5 d with standard total parenteral nutrition (TPN), glutamine-enriched TPN, or alanyl glutamine-enriched TPN. The hepatic concentration of glutathione was reduced, and the levels of thiobarbituric-acid-reactive substances (TBARS) were increased in animals receiving standard TPN. Both glutamine and alanyl glutamine supplementation normalized glutathione, but thiobarbituric-acid-reactive substance concentration was only decreased by ananyl glutamine. This effect was parallel to a partial recovery of the activity of antioxidant enzymes. Cytochrome-P450 liver content, cytochrome-P450-dependent monooxygenases, and antipyrine clearance were not modified by glutamine or alanyl glutamine. Our data suggest a better protection against free radicals by alanyl glutamine supplementation and an absence of effects of both glutamine and alanyl glutamine on liver oxidative metabolism.


Assuntos
Antioxidantes/metabolismo , Dipeptídeos/administração & dosagem , Glutamina/administração & dosagem , Fígado/metabolismo , Nutrição Parenteral Total , Animais , Catalase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Inativação Metabólica , Peroxidação de Lipídeos , Masculino , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Spine (Phila Pa 1976) ; 12(5): 433-9, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3306965

RESUMO

To date, there have been no reports of experiments designed to induce scoliosis by direct damage of different areas of the spinal cord. In a series of rabbits with medullary damage, the authors attempted selectively to interrupt the pathways that mediate proprioceptive input. Unilateral lesion of the dorsal column and posterior horn of the spinal cord was performed using three different techniques: coagulation with laser, stereotaxic microcoagulation, and longitudinal electrocoagulation. Of 32 operated rabbits, 17 developed scoliosis, exhibiting clear pathologic damage of the spinal cord. Electrophysiologic study, including EMG and analysis of the tonic -- vibratory reflex, was performed on 10 rabbits with medullary damage (scoliotic and non-scoliotic) and 12 matched controls. The data suggest disturbance of the sensory afferences that control the postural tone and consequent muscular imbalance, expressed as reduced activity in the muscles of the convex side. This work supports the view that loss of proprioceptive neural impulses caused by medullary damage can induce scoliosis.


Assuntos
Modelos Animais de Doenças , Escoliose/fisiopatologia , Medula Espinal/fisiologia , Animais , Eletrocoagulação/métodos , Eletromiografia , Terapia a Laser , Coelhos , Radiografia , Reflexo/fisiologia , Escoliose/diagnóstico por imagem , Escoliose/patologia , Medula Espinal/patologia , Técnicas Estereotáxicas
16.
Artigo em Inglês | MEDLINE | ID: mdl-8983169

RESUMO

The purpose of this investigation was to determine the effects of experimental dicrocoeliosis on the hepatic oxidative drug-metabolizing system in hamsters. Studies were carried out 80 and 120 days after infestation with an oral dose of 40 metacercariae of Dicrocoelium dendriticum. The parasitic pathology was ascertained by detection of the fluke eggs in faeces, increased serum alanine aminotransferase and aspartate aminotransferase activities, and postmortem and histological findings. Cytochrome P-450 concentration, aniline hydroxylase activity and ethoxycoumarin O-deethylase activity were significantly decreased in both groups of infected animals. Aminopyrine N-demethylase activity and erythromycin N-demethylase activity were only reduced 120 days after infection. Effects on drug metabolizing enzymes were unrelated to changes in the physical state of the microsomal membrane, as assessed by measurement of fluorescence polarization. The results of this study indicate that the capacity of the liver for handling drugs and xenobiotics may be impaired as a consequence of dicrocoeliosis.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Dicrocelíase/fisiopatologia , Fígado/enzimologia , O-Dealquilase 7-Alcoxicumarina/metabolismo , Administração Oral , Alanina Transaminase/sangue , Aminopirina N-Desmetilase/metabolismo , Análise de Variância , Anilina Hidroxilase/metabolismo , Animais , Aspartato Aminotransferases/sangue , Cricetinae , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Modelos Animais de Doenças , Fezes/microbiologia , Polarização de Fluorescência , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Oxirredutases N-Desmetilantes/metabolismo , Trematódeos/metabolismo
17.
Comp Med ; 50(2): 147-52, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10857005

RESUMO

BACKGROUND AND PURPOSE: The aim of the study reported here was to investigate the pathomorphologic changes caused by experimentally induced dicroceliosis and their correlation with hepatobiliary function. METHODS: Studies were carried out at days 80 and 120 after oral inoculation of hamsters with 40 metacercariae of Dicrocoelium dendriticum. RESULTS: The parasite-induced pathologic changes were assessed by presence of fluke eggs in feces, increased plasma alanine transaminase and aspartate transaminase activities and morphologic alterations. Dicroceliosis was characterized by bile ductular proliferation and enlargement of the bile duct surface area caused by hyperplastic cholangitis in septal bile ducts. The liver from infected animals contained portal tracts infiltrated with small to moderate numbers of lymphocytes, macrophages, and eosinophils. Simultaneously, there was an increase in portal tract collagen that extended to the interlobular septa and caused pressure atrophy of the hepatic parenchyma. The concentration of thiobarbituric acid-reactive substances and the ratio of oxidized to reduced glutathione, measured as markers of oxidative stress, were significantly increased. CONCLUSIONS: The presence of oxidative alterations could be related to the morphologic evidence of chronic inflammatory response as well as to liver cellular injury indicated by cellular swelling, and increased presence of peroxisomes and lysosomes.


Assuntos
Dicrocelíase/patologia , Dicrocelíase/fisiopatologia , Fígado/patologia , Fígado/fisiopatologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Ductos Biliares/parasitologia , Ductos Biliares/patologia , Cricetinae , Dicrocelíase/parasitologia , Dicrocoelium/imunologia , Dicrocoelium/isolamento & purificação , Dicrocoelium/patogenicidade , Eosinófilos/patologia , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Granuloma/imunologia , Granuloma/patologia , Fígado/parasitologia , Linfócitos/patologia , Macrófagos/patologia , Masculino , Mesocricetus , Óvulo/imunologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
18.
Nutr Hosp ; 17(6): 271-8, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12514919

RESUMO

Flavonoids are phenolic compounds that represent substantial constituents of the non-energetic part of the human diet. They are naturally found in vegetables, berries, fruits, wine and beer. There are more than 5000 different flavonoids. The average intake depend on the country but the average intake is approximately 23 mg/day; quercetin is predominant at 16 mg/day. Flavonoids were considered initially to be substances without any benefit for humans. Later, it has been reported that they exert multiple biological effects due to their antioxidant and free radical-scavenging abilities. Although results from different studies have demonstrated that flavonoids can act as pro-oxidant at very high doses, most investigations have reported anti-inflammatory, antiviral, or anti-allergic effects and a protective role in heart diseases, cancer and different pathologies.


Assuntos
Antioxidantes/metabolismo , Flavonoides/fisiologia , Humanos , Óxido Nítrico/metabolismo
19.
Nutr Hosp ; 19(2): 73-82, 2004.
Artigo em Espanhol | MEDLINE | ID: mdl-15049408

RESUMO

GOALS: The goal of this study is to assess the effect that supplementing parenteral diets with L-glutamine or with L-alanyl-L-glutamine has on the balance of oxidants/antioxidants in the liver and on detoxification systems mediated by P-450 cytochrome in rats. MATERIAL AND METHODS: Central catheters were inserted in the animals (n = 60) and they were randomly assigned to one of the following groups: a control group (C) with oral feeding and I.V. infusion of saline solution, a total parenteral nutrition group without glutamine (TPN without GLN), a parenteral nutrition group with glutamine supplement (TPN GLN), and a total parenteral nutrition group with a supplement of alanine-glutamine dipeptide (20 g/L) (TPN ALA-GLN). The parenteral nutrition provided was all isocaloric and isonitrogenated, and the infusions were administered at a speed of 2 ml/h over 5 days. RESULTS: In the animals of the group without GLN, the liver concentration of glutathione was reduced while the levels of thiobarbituric acid reaction products (TBARS) increased. Supplementing with either glutamine or alanine-glutamine normalized the levels of glutathione but the TBARS levels only fell in the group with the dipeptide. This effect was parallel to the partial recovery of the antioxidant enzyme activities analyzed. The liver concentrations of P-450 cytochrome, P-450 cytochrome dependent mono-oxygenases and the clearance of antipyrine were not modified by the supplements of glutamine or alanine-glutamine. CONCLUSIONS: Our data suggest a greater protection by alanine-glutamine supplements against the injury produced by free radicals during TPN and the absence of any effect with either glutamine or alanine-glutamine supplements on the oxidative metabolism of the liver.


Assuntos
Antioxidantes/fisiologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/fisiologia , Glutamina/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Nutrição Parenteral , Animais , Masculino , Ratos , Ratos Wistar
20.
Med Cutan Ibero Lat Am ; 11(2): 133-8, 1983.
Artigo em Espanhol | MEDLINE | ID: mdl-6350755

RESUMO

A review of the classification, localization, symptoms, age of on-set and incidence according to sex of the cutaneous leiomyomas in done. Besides the hereditary aspect and the association of extracutaneous lesions, especially the uterus, are considered. We present the case two sisters affected by multiple cutaneous leiomyoma in association with uterine leiomyoma. Both, members of a family in which the father and 4 of the 8 offsprings present multiple cutaneous leiomyoma, and the daughter of one of the female members (third generation) is also affected of leiomyoma of the uterus. We conclude that the presentation of the leiomyoma in this family is more than a mere coincidence and that there must be some hereditary mechanism, which is interpreted as dominant and the penetrance of the autosomal dominant gene would be about 56%.


Assuntos
Leiomioma/genética , Neoplasias Primárias Múltiplas/genética , Neoplasias Cutâneas/genética , Neoplasias Uterinas/genética , Adulto , Feminino , Genes Dominantes , Humanos , Masculino , Linhagem
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