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1.
Nutr Diabetes ; 3: e81, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23877747

RESUMO

BACKGROUND: Lycium barbarum polysaccharides (LBPs) are antioxidant and neuroprotective derivative from Wolfberry. However, whether LBP has a protective effect in non-alcoholic steatohepatitis (NASH)-induced hepatic injury is still unknown. OBJECTIVE: We aimed to study the possible hepatoprotective effects and mechanisms of LBP on a diet-induced NASH rat model. METHODS AND DESIGN: In this study, female rats were fed a high-fat diet to induce NASH with or without an oral 1 mg kg(-1) LBP feeding daily for 8 weeks. After 8 weeks, blood serum and liver samples from each rat were subjected to histological analysis, biochemical and molecular measurements. RESULTS: Compared with control rats, NASH rats showed typical NASH features including an increase in liver injury, lipid content, fibrosis, oxidative stress, inflammation and apoptosis. In contrast, NASH+LBP-co-treated rats showed (1) improved histology and free fatty acid levels; (2) re-balance of lipid metabolism; (3) reduction in profibrogenic factors through the TGF-ß/SMAD pathway; (4) improved oxidative stress through cytochrome P450 2E1-dependent pathway; (5) reduction in hepatic pro-inflammatory mediators and chemokines production; and (6) amelioration of hepatic apoptosis through the p53-dependent intrinsic and extrinsic pathways. The preventive effects of LBP were partly modulated through the PI3K/Akt/FoxO1, LKB1/AMPK, JNK/c-Jun and MEK/ERK pathways and the downregulation of transcription factors in the liver, such as nuclear factor-κB and activator protein-1. CONCLUSION: LBP is a novel hepatoprotective agent against NASH caused by abnormal liver metabolic functions.

2.
Adv Exp Med Biol ; 758: 301-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23080176

RESUMO

The carotid body (CB) plays important roles in cardiorespiratory changes in chronic and intermittent hypoxia. Pituitary adenylate cyclase activating polypeptide (PACAP) is involved in the regulation of respiratory chemoresponse. We hypothesized an upregulation of the expressions of PACAP and its receptor (PAC1) in the rat CB in chronic and intermittent hypoxia. The CB expressions of PACAP and PAC1 were examined in rats breathing 10% O(2) (in isobaric chamber for chronic hypoxia, 24 h/day) or in intermittent hypoxia (cyclic between air and 5% O(2) per minute, 8 h/day) for 7 days. Immunohistochemical studies showed that the PACAP and PAC1 proteins were localized in CB glomic clusters containing tyrosine hydroxylase. The proportional amount of cells with positive staining of PACAP and PAC1 was significantly increased in both hypoxic groups when compared with the normoxic control. In addition, the mRNA level of PAC1 expression was markedly elevated in the hypoxic groups, despite no changes in the PACAP expression. These results suggest an upregulation of PACAP and its receptor expression in the rat CB under chronic and intermittent hypoxic conditions. The PACAP binding to its receptor could activate the PKA signaling pathway leading to an increased CB excitability under hypoxic conditions.


Assuntos
Corpo Carotídeo/metabolismo , Hipóxia/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/fisiologia , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/fisiologia , Animais , Doença Crônica , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/análise , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/análise , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Regulação para Cima
3.
Histol Histopathol ; 24(9): 1161-9, 2009 09.
Artigo em Inglês | MEDLINE | ID: mdl-19609863

RESUMO

Animal models used to study the pathogenesis of non-alcoholic fatty liver disease (NAFLD) are, in general, either genetically altered, or fed with a diet that is extremely high in fat or carbohydrates. Recent findings support the role of oxidative stress, lipid peroxidation and inflammation as probable causative factors. We hypothesize that not only the amount of dietary fat, but the quality of fat is also important in inducing NAFLD. Based on previous observations that female rats fed a diet comprising unsaturated fatty acids are susceptible to liver injury, we proposed that female rats fed with a diet containing fish oil and dextrose would develop pathological and biochemical features of NAFLD. We fed a highly unsaturated fat diet (30% fish oil) to female Sprague-Dawley rats (180-200g), consumed ad libitum for 8 weeks (NAFLD; n=6-8 ). Control animals (CF; n=6-8) were fed with an isocaloric regular rat chow. At killing, blood and liver samples were collected for serum alanine aminotransferase (ALT), histology and molecular analysis. Each histological sample was evaluated for fatty liver (graded from 0 to 4+ according to the amount of fatty change), necrosis (number of necrotic foci (no./mm2) and inflammation (cells per mm2). The amount of collagen formation was estimated based on the amount of Sirius Red staining. Reverse transcriptase polymerase chain reaction (RT-PCR) was carried out for tumor necrosis factor alpha (TNF-alpha), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), adiponectin, glutathione peroxidase (GPx), superoxide dismutase (Cu/Zn SOD) and catalase (CAT). Western Blot analysis was done for cyclooxygenases-2 (COX-2), inducible nitric oxide synthase (iNOS) and nitrotyrosine. Electrophoretic mobility shift assay was performed for nuclear factor-kappa B (NF-kB) activity. NAFLD rats had a significantly higher serum ALT level, amount of collagen formation, fatty liver, necrosis and inflammation when compared with the chow-fed control rats. mRNA and protein levels of NF-kB regulated genes, which included TNF-alpha, COX-2 and iNOS were also significantly (p<0.01; p<0.01; p<0.05 respectively) upregulated in the NAFLD group when compared with the chow-fed control rats. mRNA levels of antioxidants CAT and GPX were reduced by 35% and 50% respectively in the NAFLD group. However, Cu/Zn SOD mRNA was similar in both groups. The mRNA level of adiponectin was also reduced in NAFLD group. NF-kB activity was markedly increased in the NAFLD rats (p<0.01). The level of oxidative stress, represented by the formation of nitrotyrosine, was significantly elevated in the NAFLD rats (p<0.01). We conclude that NAFLD rats demonstrated several features of NAFLD, which included fatty liver, inflammation, necrosis, increased oxidative stress, an imbalance between pro and antioxidant enzymes mRNAs, reduced adiponectin levels and upregulation of pro-inflammatory mediators. We propose that female rats fed with a diet containing highly unsaturated fatty acids are an extremely useful model for the study of NAFLD.


Assuntos
Gorduras na Dieta/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/patologia , Hepatopatias/patologia , Adiponectina/metabolismo , Administração Oral , Alanina Transaminase/sangue , Animais , Estudos de Casos e Controles , Catalase/metabolismo , Colágeno/biossíntese , Ciclo-Oxigenase 2/metabolismo , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Glutationa Peroxidase/metabolismo , Inflamação/induzido quimicamente , Inflamação/etiologia , Inflamação/patologia , Hepatopatias/etiologia , Necrose/induzido quimicamente , Necrose/etiologia , Necrose/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
4.
Adv Exp Med Biol ; 648: 207-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19536483

RESUMO

The carotid body (CB) plays important roles in cardiorespiratory changes in intermittent hypoxia (IH). Erythropoietin (EPO), a hypoxia-inducible factor (HIF)-1 target gene, is present in the chemoreceptive type-I cells in the CB but its expression and role in IH resembling sleep apnoeic conditions are not known. We hypothesized that IH upregulates the expression of EPO and its receptor (EPOr) in the rat CB. The CB expressions of EPO and EPOr were examined in rats breathing 10% O(2) (in isobaric chamber for CH, 24 hour/day) or in IH (cyclic between air and 5% O(2) per minute, 8 hour/day) for 3-28 days. Immunohistochemical studies revealed that the EPO and EPOr proteins were localized in CB glomic clusters. The proportional amount of cells with positive staining of EPO immunoreactivities was significantly increased in both IH and CH groups when compared with the normoxic control. The EPO expression was more markedly increased in the CH than that of the IH groups throughout the time course, reaching a peak level at day 14. The positive EPOr immunostaining was increased significantly in the 3-day CH group. By day 14, the EPOr expression elevated considerably at peak levels in both IH and CH rats, whereas the elevation was greater in the CH rats. These results suggest an upregulation of EPO and its receptor expression in the rat CB under IH and CH conditions, presumably mediated by the activation of HIF-1 pathway. The increased EPO binding to its receptor might play a role in the enhancement of CB excitability during the early pathogenesis in patients with sleep-disordered breathing.


Assuntos
Corpo Carotídeo/metabolismo , Eritropoetina/metabolismo , Hipóxia/metabolismo , Receptores da Eritropoetina/metabolismo , Regulação para Cima , Animais , Corpo Carotídeo/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Oxigênio/farmacologia , Ratos , Ratos Sprague-Dawley , Respiração , Transdução de Sinais , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos
5.
Histol Histopathol ; 21(11): 1157-65, 2006 11.
Artigo em Inglês | MEDLINE | ID: mdl-16874658

RESUMO

The exact functional role of nitric oxide (NO) in liver injury is currently a source of controversy. NO is enzymatically synthesized by nitric oxide synthase (NOS). In this study, we assessed the role of inducible NOS (iNOS) in carbon tetrachloride (CCl4)-induced acute liver injury using inhibitors of iNOS, and an NO donor. Adult ICR mice were injected with CCl4 with or without the iNOS inhibitors (5-methylisothiourea hemisulfate [SMT] and l-N6-(1-iminoethyl)-lysine [L-NIL]) and an NO donor (Sodium Nitroprusside [SNP]). Blood and liver tissues were collected for analysis. Immunohistochemistry (IHC), serum alanine aminotransferase (ALT), serum total 8-isoprostane analysis, RT-PCR, Western Blotting (WB) and EMSA were done. Our results showed increased levels of ALT, necrosis, total 8-isoprostane and nitrotyrosine after CCl4 administration. iNOS inhibitors and SNP abrogated these effects but the effect was more pronounced with SMT and L-NIL. RT-PCR, WB and IHC in CCl4-treated mice demonstrated upregulation of TNF-alpha, iNOS, and COX-2. The administration of iNOS inhibitors with CCl4 diminished the expression of these proinflammatory mediators. NF-kappaB was also upregulated in CCl4-treated mice and was reversed in mice pretreated with iNOS inhibitors. SNP pretreated mice also showed a lower expression of COX-2 when compared with CCl4 treated mice but TNF-alpha, iNOS and NF-kappaB activity were unaffected. We propose that a high level of nitric oxide is associated with CCl4-induced acute liver injury and the liver injury can be ameliorated by decreasing the NO level with iNOS inhibitors and an NO donor with the former more effective in reducing CCl4-induced liver injury.


Assuntos
Tetracloreto de Carbono/toxicidade , Fígado/lesões , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Alanina Transaminase/sangue , Animais , Dinoprosta/análogos & derivados , Dinoprosta/farmacologia , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Nitroprussiato/farmacologia , Tirosina/análogos & derivados , Tirosina/farmacologia
6.
Thorax ; 60(3): 239-43, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15741443

RESUMO

BACKGROUND: The clinical efficacy of inhaled corticosteroid (ICS) treatment has not been evaluated in bronchiectasis, despite the presence of chronic airway inflammation. METHODS: After three consecutive weekly visits, 86 patients were randomised to receive either fluticasone 500 mug twice daily (n = 43, 23F, mean (SD) age 57.7 (14.4) years) or matched placebo (n = 43, 34F, 59.2 (14.2) years) and reviewed regularly for 52 weeks in a double blind fashion. RESULTS: 35 and 38 patients in the fluticasone and placebo groups completed the study. Significantly more patients on ICS than on placebo showed improvement in 24 hour sputum volume (OR 2.5, 95% CI 1.1 to 6.0, p = 0.03) but not in exacerbation frequency, forced expiratory volume in 1 second, forced vital capacity, or sputum purulence score. Significantly more patients with Pseudomonas aeruginosa infection receiving fluticasone showed improvement in 24 hour sputum volume (OR 13.5, 95% CI 1.8 to 100.2, p = 0.03) and exacerbation frequency (OR 13.3, 95% CI 1.8 to 100.2, p = 0.01) than those given placebo. Logistic regression models revealed a significantly better response in sputum volume with fluticasone treatment than with placebo among subgroups of patients with 24 hour sputum volume <30 ml (p = 0.04), exacerbation frequency 5 (p = 0.03). CONCLUSIONS: ICS treatment is beneficial to patients with bronchiectasis, particularly those with P. aerurginosa infection.


Assuntos
Androstadienos/administração & dosagem , Bronquiectasia/tratamento farmacológico , Broncodilatadores/administração & dosagem , Administração por Inalação , Método Duplo-Cego , Feminino , Fluticasona , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Escarro/química , Resultado do Tratamento , Capacidade Vital/fisiologia
7.
Int J Tuberc Lung Dis ; 8(11): 1301-7, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15581196

RESUMO

SETTING: While exhaled nitric oxide (eNO) levels are reduced by inhaled corticosteroid therapy in asthma, such treatment effect is unclear in bronchiectasis. DESIGN: Stable non-smoking bronchiectasis patients were randomised to receive either fluticasone (1 mg/daily) or identical placebo via the Accuhaler device. RESULTS: Sixty non-smoking patients (38 women; mean age 56.4 +/- 12.7 years) were recruited. Of these, half received inhaled fluticasone and half placebo therapy. eNO was measured using a chemiluminescence analyser at 0, 4, 12, 24, 36 and 52 weeks. There was no significant difference in eNO levels between fluticasone and placebo patients over the study period. There was no correlation between baseline eNO with age, FEV1, FVC, 24 h sputum volume or number of bronchiectatic segments. Patients with Pseudomonas aeruginosa (PA) infection, but not their counterparts, displayed a correlation between 0- and 52-week eNO levels. PA infection was associated with significantly lower eNO levels among the patients. CONCLUSIONS: Inhaled fluticasone therapy, despite being an effective anti-inflammatory agent, has no significant effect on eNO production, either at individual time points or over the entire 52-week profile, in bronchiectasis. It appears that eNO might not reflect the extent of airway inflammation in bronchiectasis.


Assuntos
Androstadienos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Bronquiectasia/tratamento farmacológico , Bronquiectasia/metabolismo , Óxido Nítrico/metabolismo , Administração por Inalação , Adulto , Idoso , Testes Respiratórios , Método Duplo-Cego , Esquema de Medicação , Expiração , Feminino , Fluticasona , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
8.
Int J Tuberc Lung Dis ; 8(6): 691-702, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15182138

RESUMO

Bronchiectasis is a common disease in the developing world. While the aetiology of bronchiectasis is diverse, many patients suffer from idiopathic disease. Although the pathogenesis of bronchiectasis is poorly understood, there are three distinct pathogenic elements, namely infection, inflammation and enzymatic actions. These interact to perpetuate airway destruction in many cases. There are four patient stereotypes: rapidly progressive, slowly progressive, indolent disease and haemoptysis-predominant. The diagnosis of bronchiectasis is best made with high resolution computed tomography, which should be followed by delineation of aetiology and evaluation of disease severity. Management of bronchiectasis is unsatisfactory and there are no disease-modifying drugs or treatment guidelines. Specific therapy to correct an underlying defect should be instituted whenever possible, although established disease often continues to deteriorate relentlessly. Treatment with prolonged, high-dose antibiotics is useful for exacerbations and probably also for some severely affected patients with frequent exacerbations who habour Pseudomonas aeruginosa in their airways. Commencement of long-term nebulised aminoglycoside, elective in-patient intravenous antibiotic therapy, long-term oral antibiotic or low-dose macrolide therapy requires special considerations. Inhaled corticosteroid therapy reduces chemokine expression in bronchiectasis in vivo, and may be useful for some patients. For severely affected patients, the use of non-invasive positive-pressure ventilation with supplementary oxygen sometimes helps. The lack of enthusiasm about bronchiectasis has already resulted in a lack of research in the treatment of this frustrating disease, and such research needs to be encouraged.


Assuntos
Bronquiectasia , Ásia/epidemiologia , Bronquiectasia/diagnóstico , Bronquiectasia/epidemiologia , Bronquiectasia/microbiologia , Bronquiectasia/fisiopatologia , Bronquiectasia/terapia , Países em Desenvolvimento , Haemophilus influenzae/patogenicidade , Humanos , Pseudomonas aeruginosa/patogenicidade , Fatores de Virulência
9.
Histol Histopathol ; 19(1): 95-104, 2004 01.
Artigo em Inglês | MEDLINE | ID: mdl-14702176

RESUMO

The present work studied the induction of cleft palate formation in embryos developed from pregnant BALB/c mice treated orally with retinoic acid (RA). Previous studies on mature somatic cell types showed that RA exerted inhibitory effects on inducible nitric oxide synthase (iNOS) production. For the first time, our study has shown that RA actually stimulates significant expression of iNOS at specific zones of the affected embryonic palatal tissues at three consecutive stages, from gestation day 13 (GD13) to day 16 (GD16). Enzymatically, iNOS facilitates intracellular nitric oxide (NO) synthesis from L-arginine. When NO reacts with reactive superoxides it may result in irreparable cell injury. NO was also reported to induce apoptosis in some mammalian cell systems. Based on our findings, we propose that such an increase in NO production might be associated with apoptosis in the embryonic palatal tissues in the RA-treated mice. The detrimental effects of NO resulted in a reduction in proliferating palatal cells and therefore disturbed the normal plasticity of the palatal shelves. With iNOS overexpression, our findings also showed that there was significant concomitant down-regulation in the expressions of Bone Morphogenetic Proteins (BMPs) -2, 4, and 7 with regional variations particularly in the palatal mesenchymal cells for those embryos developing cleft palate. Since specific spatial and temporal expressions of BMPs -2, 4, and 7 are critical during normal palatal morphogenesis, any deficiency in the epithelial-mesenchymal interaction may result in retarding growth at the embryonic palatal shelves. Taken together, our study has demonstrated cleft palate formation in the BALB/c embryos involved overexpression of iNOS and down-regulation of BMPs-2, 4 and 7.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Teratogênicos/farmacologia , Tretinoína/farmacologia , Animais , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Fissura Palatina/induzido quimicamente , Fissura Palatina/embriologia , Fissura Palatina/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II , Fatores de Tempo , Distribuição Tecidual/efeitos dos fármacos
10.
Eur Respir J ; 21(6): 932-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12797484

RESUMO

The mechanisms for Pseudomonas aeruginosa colonisation in the airways of patients with bronchiectasis and cystic fibrosis are poorly understood. P. aeruginosa could evade mucociliary clearance by adhering to the basement membrane at areas denuded of intact respiratory epithelium. The authors have developed an in vitro model to study P. aeruginosa adherence to human basement membrane type-IV collagen by using scanning electron microscopy. P. aeruginosa adherence density was determined as the number of P. aeruginosa per 20 microscope fields (2,000x) to log inocular size after incubation at 37 degrees C for 45 min. The presence of phytohaemagglutinin (PHA)-E, which binds specifically to D-galactose-beta1-4-D-N-acetylglucosamine, significantly reduced P. aeruginosa adherence density compared with control. The presence of heparin and calcium also significantly reduced P. aeruginosa adherence density. P. aeruginosa adherence was not affected by the presence of proline, trans-hydroxyproline, glycine, galactose, N-acetylneuraminic acid, N-acetylglucosamine or Arachis hypogea. Pseudomonas aeruginosa adherence probably acts via recognition of the D-galactose-beta1-4-D-N-acetylglucosamine sequence on type-IV collagen and this process could be inhibited by heparin and calcium. As persistent Pseudomonas aeruginosa colonisation is detrimental to patients with cystic fibrosis and bronchiectasis and there is currently no effective treatment for its eradication, these results could lead to novel therapy for persistent Pseudomonas aeruginosa infection.


Assuntos
Aderência Bacteriana/fisiologia , Membrana Basal/fisiopatologia , Bronquiectasia/fisiopatologia , Colágeno Tipo IV/fisiologia , Fibrose Cística/fisiopatologia , Pseudomonas aeruginosa/fisiologia , Aminoácidos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Membrana Basal/efeitos dos fármacos , Membrana Basal/ultraestrutura , Carboidratos/farmacologia , Colágeno Tipo IV/efeitos dos fármacos , Colágeno Tipo IV/ultraestrutura , Contagem de Colônia Microbiana , Humanos , Técnicas In Vitro , Íons/farmacologia , Lectinas/farmacologia , Microscopia Eletrônica de Varredura , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/ultraestrutura
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 21(1): 52-4, 2003 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-12674624

RESUMO

OBJECTIVE: The aim of this study was to observe the expression of ciliary neurotrophic factors (CNTFs) in the facial motor neurons in rats during facial nerve regeneration. METHODS: The expression amount of CNTFs in eight groups was determined with immunohistochemical staining and image analysis. RESULTS: The expression of CNTFs increased during the process of nerve regeneration, and reached the maximum one-week and one-month after nerve injury respectively. After one month, the intensity of CNTFs reduced gradually. The expression of recombinant human bone morphogenetic protein-2 (rhBMP-2) did not show distinct difference comparing with the control, but beta transforming growth factors (TGF-beta) benefited the expression of CNTFs during nerve regeneration. CONCLUSION: The endogenous CNTFs promotes the axon outgrow during regeneration, and TGF-beta promotes the expression of CNTFs to rescue motoneuron during facial nerve regeneration.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Fator Neurotrófico Ciliar/biossíntese , Nervo Facial/fisiopatologia , Regeneração Nervosa , Fator de Crescimento Transformador beta/metabolismo , Animais , Fator Neurotrófico Ciliar/genética , Nervo Facial/metabolismo , Traumatismos do Nervo Facial/fisiopatologia , Masculino , Neurônios Motores/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes
12.
Respir Med ; 97(1): 59-64, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12556012

RESUMO

Bronchiectasis is characterized pathologically by permanent abnormal bronchial dilation, and clinically by chronic sputum production. Aquaporin 3 (AQP3), a recently described water channel that is also found in large airway cell membrane, could play a role in the pathogenesis and particularly that of bronchorrhea in bronchiectasis. However, little is known of its in vivo distribution and physiological role in human airways. We have, therefore, performed this quantitative immunohistochemistry study on endobronchial biopsies to evaluate the expression and clinical relevance of AQP3 in patients with idiopathic bronchiectasis (n = 25, 15 F, 64.3 +/- 11.5 years) and control subjects (n = 14, 5 F, 57.5 +/- 12.0 years). Quantitative image analysis was performed to evaluate the expression of AQP3 in the bronchial epithelial cells. Our results show that AQP3 was predominantly expressed in the basal cells of the epithelial layer in both groups. Expression of AQP3 was significantly reduced in the basal, but not columnar, epithelial cells in bronchiectasis compared with control airways (p = 0.02, 0.35). Only bronchiectatic patients with regular sputum production, but not their counterparts, had significant downregulation of epithelial AQP3 expression compared with control airways (p = 0.004, 0.24). Our findings suggest that AQP3 could have an important role in the pathogenesis of increased mucus production in bronchiectasis.


Assuntos
Aquaporinas/metabolismo , Bronquiectasia/metabolismo , Aquaporina 3 , Brônquios/metabolismo , Bronquiectasia/fisiopatologia , Regulação para Baixo , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Capacidade Vital/fisiologia
13.
Eur Respir J ; 20(1): 170-6, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12166566

RESUMO

The progressive bronchial dilatation in bronchiectasis is likely to be the result of continued airway matrix destruction, although little is known about the role of neutrophil matrix metalloproteinases (MMPs) in this process. Immunohistochemistry has been used to investigate the expression and cellular localisation of MMP-8 and MMP-9 in bronchiectatic airways in vivo. Endobronchial biopsies were taken from 25 bronchiectatic patients, and from the right lower lobe in 14 control subjects. MMP-8, MMP-9, neutrophils and macrophages were stained with monoclonal antibodies and quantified as positive cell x mm(-2) of the lamina propria by using an image analysis system. There were significantly higher densities of MMP-8 and MMP-9 positive cells in the lamina propria of bronchiectatic than control airways. In bronchiectatic airways, the densities of MMP-8 and MMP-9 positive cells correlated with each other and with neutrophil density, but not with macrophage density. In control airways, a significant correlation was found between MMP-8 with neutrophil and MMP-9 with macrophage densities. An overexpression of neutrophil matrix metalloproteinases in bronchiectatic airways could help explain the continuation of airway destruction in bronchiectasis. In view of the clinical availability of matrix metalloproteinase antagonists, the results presented here could have a significant impact on the development of novel therapies of this untreatable disease.


Assuntos
Bronquiectasia/imunologia , Bronquiectasia/patologia , Metaloproteinase 8 da Matriz/análise , Metaloproteinase 8 da Matriz/imunologia , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/imunologia , Idoso , Brônquios/imunologia , Brônquios/patologia , Broncoscopia , Feminino , Humanos , Contagem de Leucócitos , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/patologia , Testes de Função Respiratória
14.
Lung ; 179(2): 83-91, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11733851

RESUMO

Since little is known of the effects of age, gender, and body size on exhaled nitric oxide (NO) production, we have conducted a prospective study to examine these factors in a healthy nonsmoking women (mean age +/- SD 47.7 +/- 15.8, range 20-79 years). Exhaled NO was measured by an automatic chemiluminescence analyzer (Sievers NO Analyser 280) at steady expiration. Men had significantly higher exhaled NO levels than women (p = 0.001). Although exhaled NO levels did not correlate with age (r = 0.12, p = 0.17), it correlated significantly with height (r = 0.23, p = 0.02), weight (r = 0.34, p


Assuntos
Envelhecimento/metabolismo , Constituição Corporal , Testes Respiratórios , Óxido Nítrico/análise , Caracteres Sexuais , Adulto , Idoso , Índice de Massa Corporal , Superfície Corporal , Testes Respiratórios/instrumentação , Feminino , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência
15.
Am J Physiol Gastrointest Liver Physiol ; 281(6): G1348-56, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11705739

RESUMO

Alcoholic liver injury is more severe and rapidly developing in women than men. To evaluate the reason(s) for these gender-related differences, we determined whether pathogenic mechanisms important in alcoholic liver injury in male rats were further upregulated in female rats. Male and age-matched female rats (7/group) were fed ethanol and a diet containing fish oil for 4 wk by intragastric infusion. Dextrose isocalorically replaced ethanol in control rats. We analyzed liver histopathology, lipid peroxidation, cytochrome P-450 (CYP)2E1 activity, nonheme iron, endotoxin, nuclear factor-kappa B (NF-kappa B) activation, and mRNA levels of cyclooxygenase-1 (COX-1) and COX-2, tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-2 (MIP-2). Alcohol-induced liver injury was more severe in female vs. male rats. Female rats had higher endotoxin, lipid peroxidation, and nonheme iron levels and increased NF-kappa B activation and upregulation of the chemokines MCP-1 and MIP-2. CYP2E1 activity and TNF-alpha and COX-2 levels were similar in male and female rats. Remarkably, female rats fed fish oil and dextrose also showed necrosis and inflammation. Our findings in ethanol-fed rats suggest that increased endotoxemia and lipid peroxidation in females stimulate NF-kappa B activation and chemokine production, enhancing liver injury. TNF-alpha and COX-2 upregulation are probably important in causing liver injury but do not explain gender-related differences.


Assuntos
Quimiocinas/fisiologia , Endotoxinas/fisiologia , Hepatopatias Alcoólicas/fisiopatologia , Estresse Oxidativo , Caracteres Sexuais , Animais , Quimiocina CCL2/genética , Quimiocina CXCL2 , Quimiocinas/genética , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Citocromo P-450 CYP2E1/metabolismo , Gorduras Insaturadas na Dieta/administração & dosagem , Endotoxemia/fisiopatologia , Etanol/administração & dosagem , Feminino , Óleos de Peixe/administração & dosagem , Ferro/metabolismo , Isoenzimas/genética , Peroxidação de Lipídeos , Fígado/química , Fígado/metabolismo , Fígado/patologia , Hepatopatias Alcoólicas/patologia , Masculino , Proteínas de Membrana , NF-kappa B/metabolismo , Prostaglandina-Endoperóxido Sintases/genética , RNA Mensageiro/análise , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/genética , Aumento de Peso
16.
J Pharmacol Exp Ther ; 299(3): 832-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11714866

RESUMO

We investigated the potential of arginine to reverse pathological changes in alcohol-induced liver injury. Four groups (six rats/group) of male Wistar rats were fed a fish oil-ethanol diet for 6 (group 2) or 8 (group 1) weeks. Rats in group 3 were fed fish oil-ethanol for 6 weeks, after which they were administered arginine with fish oil-ethanol for an additional 2 weeks. Rats in group 4 were fed fish oil-dextrose for 8 weeks. Liver samples were analyzed for histopathology, lipid peroxidation, cytochrome P4502E1 activity, nuclear factor-kappaB, and levels of messenger RNA for tumor necrosis factor-alpha, cyclooxygenase-2, and inducible nitric oxide synthase. Concentrations of endotoxin were measured in plasma. The most severe inflammation and fibrosis was detected in groups 1 and 2, as were the highest levels of endotoxin, lipid peroxidation, cytochrome P450 2E1 activity, activation of nuclear factor-kappaB, and mRNA levels for tumor necrosis factor-alpha, cyclooxygenase-2, and inducible nitric oxide synthase. Plasma nitric oxide was also increased as was nitrotyrosine in liver. After arginine was administered, there was marked improvement in the pathological changes accompanied by decreased levels of endotoxin, lipid peroxidation, activation of nuclear factor-kappaB, tumor necrosis factor-alpha, cyclooxygenase-2, inducible nitric oxide, and nitrotyrosine staining. The therapeutic effects of arginine are probably secondary to increased levels of nitric oxide but other effects of arginine cannot be excluded.


Assuntos
Arginina/uso terapêutico , Etanol/toxicidade , Cirrose Hepática/prevenção & controle , Tirosina/análogos & derivados , Animais , Ciclo-Oxigenase 2 , Modelos Animais de Doenças , Regulação para Baixo , Interações Medicamentosas , Endotoxinas/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Isoenzimas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Cirrose Hepática Alcoólica/prevenção & controle , Masculino , Proteínas de Membrana , NF-kappa B/metabolismo , Óxido Nítrico/sangue , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Tirosina/metabolismo
17.
Histol Histopathol ; 16(4): 1013-9, 2001 10.
Artigo em Inglês | MEDLINE | ID: mdl-11642720

RESUMO

The aim of our study was to document whether relationships existed among bone morphogenetic proteins (BMPs), peripheral nerve and neoplastic lesions of nerve sheath tumors. The mRNA transcriptions of BMP-2, 3, 4 and 5 in 10 cases of schwannoma, three cases of malignant schwannoma and two cases of trigeminal neuralgia were detected using an in situ hybridization technique. Our results demonstrated that the myelin sheaths of Schwann cell from the peripheral neuroectomy of trigeminal neuralgia positively expressed mRNA of BMP-2, 3, 4, and 5. The most interesting finding was that the nerve fibers of trigeminal nerve showed only BMP-2 positive staining. All of the neoplastic lesions of nerve sheath showed a consistent but variant expression of BMP-2, 3, 4, and 5. The expression signals of BMP-2, 3, 5 mRNA in malignant schwannoma were relatively lower than in benign lesions except for the expression of BMP-4 mRNA. Our results indicated that selected members of BMPs were expressed in the peripheral nerves that might contribute to the health maintenance, proliferation, regeneration and neoplastic transformation of the peripheral nerve system. Furthermore, the effects of BMP-2, 3, 4 and 5 on peripheral nervous system during neoplastic transformation might be widespread, diverse and antagonistic.


Assuntos
Proteínas Morfogenéticas Ósseas/biossíntese , Neoplasias do Sistema Nervoso/metabolismo , Neurilemoma/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , RNA Mensageiro/biossíntese , Nervo Trigêmeo/metabolismo , Adulto , Proteínas Morfogenéticas Ósseas/genética , DNA Complementar/biossíntese , Feminino , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Transcrição Gênica
18.
Respir Med ; 95(10): 792-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11601743

RESUMO

Bronchiectasis is increasingly being recognized as an inflammatory condition of the airways in which pathological permanent dilation occurs. We have obtained endobronchial biopsies in 14 patients with stable bronchiectasis and 15 control subjects. Airway neutrophils, macrophages and tumour necrosis factor-alpha (TNFalpha)-positive cells were stained with monoclonal antibodies and the densities of positive cells in the lamina propria were determined by using a computer image analyser. There was significantly higher neutrophil, macrophage and TNFalpha-positive cell densities in the lamina propria of bronchiectatic than control airways (P < 0.001, P < 0.001 and P=0.0002, respectively). Airway neutrophil density in bronchiectasis but not in controls, correlated with TNFalpha-positive cell density (r=0.71, P=0.004). A significant correlation between airway macrophage and TNFalpha-positive cell densities was demonstrated in both control and bronchiectatic airways (r=0.63, P=0.016 and r=0.60, P=0.02 respectively). Neutrophil density negatively correlated with per cent forced vital capacity (FVC%) predicted among patients with bronchiectasis (r=-0.53, P=0.04). Bronchiectasis patients who were regular sputum producers had a significantly higher macrophage, but not neutrophil density than their counterparts (P=0.02 and P=0.48 respectively). Our original findings suggest that airway macrophages could contribute to neutrophil influx into airway walls through their production of TNFalpha and therefore play an important role in the pathogenesis of bronchiectasis.


Assuntos
Bronquiectasia/imunologia , Pulmão/imunologia , Macrófagos/patologia , Neutrófilos/patologia , Fator de Necrose Tumoral alfa/metabolismo , Idoso , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biomarcadores/análise , Bronquiectasia/patologia , Broncoscopia , Estudos de Casos e Controles , Contagem de Células , Feminino , Humanos , Imuno-Histoquímica , Pulmão/patologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Elastase Pancreática/análise , Estatísticas não Paramétricas
19.
J Pharmacol Exp Ther ; 299(2): 638-44, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11602676

RESUMO

We investigated the potential of dietary saturated fatty acids to reverse alcoholic liver injury despite continued administration of alcohol. Five groups (six rats/group) of male Wistar rats were studied. Rats in groups 1 and 2 were fed a fish oil-ethanol diet for 8 and 6 weeks, respectively. Rats in groups 3 and 4 were fed fish oil and ethanol for 6 weeks before being switched to isocaloric diets containing ethanol with palm oil (group 3) or medium-chain triglycerides (MCTs, group 4) for 2 weeks. Rats in group 5 were fed fish oil and dextrose for 8 weeks. Liver samples were analyzed for histopathology, lipid peroxidation, nuclear factor-kappaB (NF-kappaB) activation, and mRNAs for cyclooxygenase-2 (Cox-2) and tumor necrosis factor-alpha (TNF-alpha). Endotoxin in plasma was determined. The most severe inflammation and fibrosis were detected in groups 1 and 2, as were the highest levels of endotoxin, lipid peroxidation, activation of NF-kappaB, and mRNAs for Cox-2 and TNF-alpha. After the rats were switched to palm oil or MCT, there was marked histological improvement with decreased levels of endotoxin and lipid peroxidation, absence of NF-kappaB activation, and reduced expression of TNF-alpha and Cox-2. A diet enriched in saturated fatty acids effectively reverses alcohol-induced necrosis, inflammation, and fibrosis despite continued alcohol consumption. The therapeutic effects of saturated fatty acids may be explained, at least in part, by reduced endotoxemia and lipid peroxidation, which in turn result in decreased activation of NF-kappaB and reduced levels of TNF-alpha and Cox-2.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/dietoterapia , Etanol/farmacologia , Ácidos Graxos/farmacologia , Cirrose Hepática Alcoólica/dietoterapia , Anilina Hidroxilase/metabolismo , Animais , Depressores do Sistema Nervoso Central/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Ciclo-Oxigenase 2 , Dieta , Endotoxinas/sangue , Etanol/sangue , Proteínas I-kappa B/metabolismo , Isoenzimas/biossíntese , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática Alcoólica/patologia , Masculino , NF-kappa B/metabolismo , Ferroproteínas não Heme/metabolismo , Prostaglandina-Endoperóxido Sintases/biossíntese , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
20.
J Am Coll Cardiol ; 38(4): 1207-15, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11583905

RESUMO

OBJECTIVES: The goal of this study was to compare the relative efficacy of an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin receptor blocker (ARB) in suppressing the histopathologic changes that lead to ventricular remodeling after an acute myocardial infarction (AMI). BACKGROUND: Myocardial interstitial fibrosis in the noninfarcted region is a major histologic landmark resulting in cardiac dysfunction after AMI. However, the relative potency of an ACE inhibitor and ARB on suppressing the histopathologic changes was unclear. METHODS: Rats with AMI were randomized to fosinopril, valsartan or a combination of the two drugs for two or four weeks. The total, type I and type III collagen and activated fibroblasts and macrophages were quantified by histomorphometry. The expression of transforming growth factor-beta 1 (TGF-beta 1) messenger ribonucleic acid (mRNA) was determined by reverse transcription polymerase chain reaction. RESULTS: Acute myocardial infarction resulted in significant elevation of total (p < 0.001) and type I (p < 0.001) collagen and a twofold increase in TGF-beta 1 mRNA expression (p < 0.001) in the septum at two and four weeks. Macrophages and activated myofibroblasts infiltrated extensively in the infarct zone. Treatment with valsartan or combination therapy normalized the total and type I collagen (p < 0.001) as well as TGF-beta 1 mRNA level (p < 0.01) in the septum and was associated with the suppression of macrophages and myofibroblasts in the infarct zone (p < 0.01). Fosinopril was less effective than valsartan or combination therapy. CONCLUSIONS: The use of valsartan, especially combined with fosinopril, was more effective than fosinopril in the suppression of histopathologic changes resulting in cardiac remodeling after AMI. This study has important therapeutic implications in pharmacotherapy of clinical practice.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Fosinopril/farmacologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Tetrazóis/farmacologia , Valina/farmacologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Colágeno/metabolismo , Combinação de Medicamentos , Fibrose , Masculino , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Valina/análogos & derivados , Valsartana
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