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2.
Animal ; 11(9): 1626-1635, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28115030

RESUMO

Studies aimed to assess up to what extent farming and transport previous to slaughtering might affect physiology and meat quality in young goat kids are needed, with the ultimate purpose of promoting practices that minimize stress in these animals. In this regard the effects of on-farm management and transport duration on some physiological responses and meat quality parameters in goat kids were assessed. Two farms representing 'high' and 'low' welfare-friendly management practices were selected. In total, 32 suckling kids were withdrawn from each farm, transported by road for 2 or 6 h, and then slaughtered. Blood samples were collected both on-farm and in the slaughterhouse, and biochemistry, cell counts and haematocrit were determined. After slaughtering, carcass quality parameters were measured. Longissimus dorsi muscle was dissected and pH, colour parameters, water holding capacity and shear force were measured throughout 8-day ageing period. Results indicate that, regardless its duration, transport caused significant effects on some blood parameters suggesting stress in live animals, like glucose, cortisol or creatine kinase. Despite the marked stress status in animals, this condition was not decisively reflected on L. dorsi quality parameters, but some effects were observed regarding fat cover in carcasses and colour parameters. The results suggest that postmortem changes throughout ageing were more decisive in terms of meat quality than stressful management either on-farm or during transport.


Assuntos
Bem-Estar do Animal , Animais Lactentes/fisiologia , Cabras/fisiologia , Carne Vermelha/normas , Estresse Fisiológico , Matadouros , Agricultura , Animais , Cor , Creatina Quinase/sangue , Fazendas , Hidrocortisona/sangue , Concentração de Íons de Hidrogênio , Masculino , Fenótipo , Mudanças Depois da Morte , Fatores de Tempo , Meios de Transporte
3.
Actas Dermosifiliogr ; 107(4): e19-22, 2016 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26706712

RESUMO

The use of ultrasound imaging has recently been increasing in numerous dermatologic diseases. This noninvasive technique provides additional details on the structure and vascularization of skin lesions. Kaposi sarcoma is a vascular tumor that typically arises in the skin and mucosas. It can spread to lymph nodes and internal organs. We performed B-mode and color Doppler ultrasound studies in 3 patients with a clinical diagnosis of Kaposi sarcoma confirmed by histological examination. We found differences in the ultrasound pattern between nodular and plaque lesions, in both B-mode and color Doppler. We believe that skin ultrasound imaging could be a useful technique for studying cutaneous Kaposi sarcoma, providing additional information on the structural and vascular characteristics of the lesion.


Assuntos
Sarcoma de Kaposi/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
5.
Environ Toxicol Pharmacol ; 36(1): 125-34, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23603465

RESUMO

The aim of the current research was to assess the possible influence of copper sulphate contamination on the antioxidant enzymatic defenses and lipid peroxidation (LPO) in the mosquitofish (Gambusia holbrooki). Quadruplicated lots of this fish were exposed to three increasing sub-lethal concentrations of Cu (0.10; 0.17 and 0.25mgCu/L) and a control without Cu for 20 days. Previous to laboratory acclimation, 8 fish were taken to define the initial population. At the end of the trials, 12 fish/sex/treatment were sampled for the determination of levels of copper in gills, metallothioneins (MTs) content, total lipids, fatty acids profiles and antioxidant enzymatic activity, as well as lipid peroxidation. Most of the antioxidant enzymatic defenses assayed were not activated and lipid peroxidation decreased significantly in fish exposed to any concentration of copper applied. This leads us to presume the existence of a protective mechanism against peroxidation other than the enzymatic antioxidant defense, which could be related to the observed increase of copper content in the gills.


Assuntos
Sulfato de Cobre/toxicidade , Ciprinodontiformes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Sulfato de Cobre/farmacocinética , Feminino , Proteínas de Peixes/metabolismo , Brânquias/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Metalotioneína/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/farmacocinética
6.
Pharmacol Res ; 66(2): 144-53, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22569414

RESUMO

Alkaline phosphatase (AP) inactivates bacterial lipopolysaccharide and may therefore be protective. The small intestine and colon express intestinal (IAP) and tissue nonspecific enzyme (TNAP), respectively. The aim of this study was to assess the therapeutic potential of exogenous AP and its complementarity with endogenous enzyme protection in the intestine, as evidenced recently. IAP was given to rats by the oral or intrarectal route (700U/kgday). Oral budesonide (1mg/kgday) was used as a reference treatment. Treatment with intrarectal AP resulted in a 54.5% and 38.0% lower colonic weight and damage score, respectively, and an almost complete normalization of the expression of S100A8, LCN2 and IL-1ß (p<0.05). Oral AP was less efficacious, while budesonide had a more pronounced effect on most parameters. Both oral and intrarectal AP counteracted bacterial translocation effectively (78 and 100%, respectively, p<0.05 for the latter), while budesonide failed to exert a positive effect. AP activity was increased in the feces of TNBS colitic animals, associated with augmented sensitivity to the inhibitor levamisole, suggesting enhanced luminal release of this enzyme. This was also observed in the mouse lymphocyte transfer model of chronic colitis. In a separate time course study, TNAP was shown to increase 2-3 days after colitis induction, while dextran sulfate sodium was a much weaker inducer of this isoform. We conclude that exogenous AP exerts beneficial effects on experimental colitis, which includes protection against bacterial translocation. AP of the tissue-nonspecific isoform is shed in higher amounts to the intestinal lumen in experimental colitis, possibly aiding in intestinal protection.


Assuntos
Fosfatase Alcalina/uso terapêutico , Translocação Bacteriana/efeitos dos fármacos , Colite/tratamento farmacológico , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/farmacologia , Animais , Colite/induzido quimicamente , Colite/enzimologia , DNA Bacteriano/análise , Sulfato de Dextrana , Modelos Animais de Doenças , Fezes/enzimologia , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Fígado/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Peroxidase/metabolismo , Ratos , Ratos Wistar , Ácido Trinitrobenzenossulfônico
7.
Nutr Hosp ; 27(5): 1626-30, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23478715

RESUMO

BACKGROUND AIMS: Body composition measurements seem to be not reliable enough in obese patients. Our aim was to compare single frequency-bioelectrical impedance (SF-BIA) analysis; foot-to-foot impedance meters (FFI) or upper body fat analysers (UBFA) and DXA (Dual-energy X-ray absorptiometry) in severely obese patients. PATIENTS AND METHODS: Cross-sectional study including 40 severely obese patients. Bioelectrical impedance was performed for SF-BIA (Holtain (H) and OMRON BF 500 (O500)), FFI (Tanita TBF-300 (T)) and UBFA (Omron BF 300 (O300)). DXA scans were performed using a Lunar iDXA. The data were analysed using Pearson's correlation and Bland Altman plots were also drawn to evaluate any agreements. RESULTS: The percentage and total body fat values were 49.2% and 55.2 kg measured with DXA, 44.3%/53.4 kg with O300, 50.6%/58.3 kg with O500, 45.4%/55.4 kg with H and 49.1%/60.3 kg with T. The Holtain BIA showed the worst correlation with DXA for both %BF and FFM. Although the measurements of % body fat, fat mass and fat-free mass were significantly correlated with DXA, each method showed wide limits of agreement, although T was most closely correlated with DXA. CONCLUSION: Compared to DXA, FFI and UBFA could be useful for assessing body composition in severely obese people, although they appeared to underestimate %BF and FM and their limits of agreement were too wide.


Assuntos
Composição Corporal/fisiologia , Obesidade/metabolismo , Absorciometria de Fóton , Tecido Adiposo/patologia , Adulto , Anatomia Transversal , Índice de Massa Corporal , Impedância Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/patologia , Reprodutibilidade dos Testes
8.
Crit Rev Food Sci Nutr ; 51(4): 331-62, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21432698

RESUMO

Flavonoids are a family of polyphenolic compounds which are widespread in nature (vegetables) and are consumed as part of the human diet in significant amounts. There are other types of polyphenols, including, for example, tannins and resveratrol. Flavonoids and related polyphenolic compounds have significant antiinflammatory activity, among others. This short review summarizes the current knowledge on the effects of flavonoids and related polyphenolic compounds on inflammation, with a focus on structural requirements, the mechanisms involved, and pharmacokinetic considerations. Different molecular (cyclooxygenase, lipoxygenase) and cellular targets (macrophages, lymphocytes, epithelial cells, endothelium) have been identified. In addition, many flavonoids display significant antioxidant/radical scavenging properties. There is substantial structural variation in these compounds, which is bound to have an impact on their biological profile, and specifically on their effects on inflammatory conditions. However, in general terms there is substantial consistency in the effects of these compounds despite considerable structural variations. The mechanisms have been studied mainly in myeloid cells, where the predominant effect is an inhibition of NF-κB signaling and the downregulation of the expression of proinflammatory markers. At present there is a gap in knowledge of in vitro and in vivo effects, although the pharmacokinetics of flavonoids has advanced considerably in the last decade. Many flavonoids have been studied for their intestinal antiinflammatory activity which is only logical, since the gastrointestinal tract is naturally exposed to them. However, their potential therapeutic application in inflammation is not restricted to this organ and extends to other sites and conditions, including arthritis, asthma, encephalomyelitis, and atherosclerosis, among others.


Assuntos
Flavonoides/administração & dosagem , Inflamação/prevenção & controle , Fenóis/administração & dosagem , Animais , Dieta , Flavonoides/metabolismo , Humanos , Inflamação/dietoterapia , Inflamação/tratamento farmacológico , Fenóis/metabolismo , Polifenóis
9.
Br J Pharmacol ; 160(7): 1714-26, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20649574

RESUMO

BACKGROUND AND PURPOSE: Cyclooxygenase 2 (COX-2) is involved in inflammatory bowel disease, but the effect of flavonoids at the intestinal epithelial level is unknown. We aimed to characterize the effect and structure-activity relationship of nine selected flavonoids on COX-2 expression in intestinal epithelial cell (IEC)18 cells. We also investigated the signal transduction pathway(s) responsible for the effects observed. EXPERIMENTAL APPROACH: Intestinal epithelial cell 18, a non-tumour cell line with intestinal epithelial phenotype, was used. COX-2 was measured by Western blot and the involvement of the NF-kappaB pathway assessed by Western blot, pharmacological inhibition, luciferase reporter assays and nuclear translocation experiments. KEY RESULTS: The effect of flavonoids on COX-2 expression depended on the experimental conditions tested [non-stimulated and lipopolysaccharide (LPS)-stimulated]. Flavonoids caused an increase in COX-2 expression and NF-kappaB-dependent gene transcription under basal conditions. Conversely, under LPS stimulation flavonoids increased, decreased or did not affect COX-2 levels depending on the specific type. Variable effects were observed on extracellular signal regulated kinase/p38/c-Jun N-terminal kinase phosphorylation and p50/65 nuclear translocation. CONCLUSION AND IMPLICATIONS: The effect of flavonoids on COX-2 expression depended on the balance of the interference with IkappaB-alpha phosphorylation and other signalling targets, and therefore depends on the experimental conditions and on the type of flavonoids. This is expected to result in different effects in inflammatory conditions. In general, flavonoids may limit epithelial COX-2 expression in inflammatory conditions while favouring it when inflammation is not present.


Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Células Epiteliais/efeitos dos fármacos , Flavonoides/farmacologia , Mucosa Intestinal/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Animais , Western Blotting , Linhagem Celular , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/biossíntese , Inibidores de Ciclo-Oxigenase 2/química , Relação Dose-Resposta a Droga , Células Epiteliais/enzimologia , Células Epiteliais/imunologia , Flavonoides/química , Mucosa Intestinal/citologia , Mucosa Intestinal/enzimologia , Mucosa Intestinal/imunologia , L-Lactato Desidrogenase/metabolismo , Lipopolissacarídeos/farmacologia , Luciferases/genética , Estrutura Molecular , NF-kappa B/genética , NF-kappa B/metabolismo , Plasmídeos , Transporte Proteico , Ratos
10.
Clin Microbiol Infect ; 15(5): 443-53, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19368547

RESUMO

Streptococcus pneumoniae infections are often difficult to diagnose accurately, as it is not uncommon for clinical samples to be culture-negative, particularly after antibiotic administration. The rapid Binax NOW S. pneumoniae urinary antigen test lacks specificity in children, owing to pneumococcal antigen reactions in children who are nasopharyngeal carriers of S. pneumoniae. A western blot assay with a specific polyclonal antibody was developed for direct detection of the putative proteinase maturation protein A (PpmA) in urine samples from children with pneumococcal infections. The sensitivity and specificity of the assay were 66.7% and 100%, respectively. Previous antibiotic treatment or S. pneumoniae nasopharyngeal colonization did not affect PpmA antigenuria. Results also demonstrated the presence of PpmA cross-reactive epitopes in commensal bacteria that co-colonize the nasopharyngeal niche, although the non-pneumococcal cross-reactive protein(s) did not interfere with the detection assay. S. pneumoniae PpmA in the urine of children with pneumococcal infections may be a marker that has the potential to be used in the clinical diagnosis of pneumococcal infection.


Assuntos
Antígenos de Bactérias/urina , Proteínas de Bactérias/urina , Infecções Pneumocócicas/diagnóstico , Streptococcus pneumoniae/imunologia , Urina/microbiologia , Sequência de Aminoácidos , Animais , Western Blotting/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Dados de Sequência Molecular , Coelhos , Sensibilidade e Especificidade , Alinhamento de Sequência
11.
Br J Pharmacol ; 154(4): 825-32, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18536735

RESUMO

BACKGROUND AND PURPOSE: Bovine glycomacropeptide (BGMP) is an inexpensive, non-toxic milk peptide with anti-inflammatory effects in rat experimental colitis but its mechanism of action is unclear. It is also unknown whether BGMP can ameliorate inflammation in proximal regions of the intestine. Our aim was therefore two-fold: first, to determine the anti-inflammatory activity of BGMP in the ileum; second, to characterise its mechanism of action. EXPERIMENTAL APPROACH: We used a model of ileitis induced by trinitrobenzenesulphonic acid in rats. Rats were treated orally with BGMP and its efficacy compared with that of oral 5-aminosalicylic acid or vehicle, starting 2 days before ileitis induction. KEY RESULTS: BGMP pretreatment (500 mg kg(-1) day(-1)) resulted in marked reduction of inflammatory injury, as assessed by lower extension of necrosis and damage score, myeloperoxidase, alkaline phosphatase, inducible nitric oxide synthase, interleukin 1beta, tumour necrosis factor and interleukin 17. These effects were generally comparable to those of 5-aminosalicylic acid (200 mg kg(-1) day(-1)). Neither compound affected the production of interferon gamma, tumour necrosis factor and interleukin 2 by mesenteric lymph node cells isolated from animals with ileitis. The expression of Foxp3 was increased in ileitis and not reduced significantly by BGMP or aminosalicylate treatment. CONCLUSIONS AND IMPLICATIONS: These results demonstrate that BGMP has anti-inflammatory activity in the ileum with similar efficacy to 5-aminosalicylic acid. The mechanism of action may involve Th17 and regulatory T cells and perhaps macrophages but probably not Th1 lymphocytes. Patients with Crohn's ileitis may benefit from treatment with BGMP.


Assuntos
Anti-Inflamatórios/farmacologia , Regulação para Baixo/efeitos dos fármacos , Glicopeptídeos/farmacologia , Ileíte/tratamento farmacológico , Administração Oral , Animais , Bovinos , Modelos Animais de Doenças , Feminino , Ileíte/fisiopatologia , Interleucina-17/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mesalamina/farmacologia , Ratos , Ratos Wistar , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Ácido Trinitrobenzenossulfônico
12.
Br J Pharmacol ; 151(2): 206-15, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17375077

RESUMO

BACKGROUND AND PURPOSE: The nitrogen-containing bisphosphonates are drugs used successfully in the treatment of osteoporosis. They act inhibiting farnesyl diphosphate synthase. This mechanism may also produce anti-inflammatory effects. The therapeutic activity of alendronate was tested in vivo using a model of inflammatory bowel disease. EXPERIMENTAL APPROACH: The trinitrobenzenesulfonic acid model of colitis in the rat was used. Rats were treated orally with alendronate and its efficacy compared with that of oral sulphasalazine or vehicle, starting 2 h after colitis induction. The status of the animals was assessed 5 days later. KEY RESULTS: Alendronate treatment (25 or 75 mg kg(-1) day(-1)) resulted in a decrease in the colonic damage score and loss of body weight (at 25 mg kg(-1) day(-1) only). This was associated to a dramatic reduction in the mRNA levels of interleukin 1 beta (IL-1 beta), monocyte chemoattractant protein 1 (MCP-1) and interleukin 1 receptor antagonist (IL-1 ra). The magnitude of the beneficial effect was comparable to that of sulphasalazine (at a 6-20 fold higher dose). Thus sulphasalazine post-treatment reduced the mRNA levels of IL-1 beta/IL-1 ra and MCP-1 to the same extent as alendronate and additionally lowered colonic alkaline phosphatase activity, but failed to affect body weight loss or colonic damage score. Alendronate failed to exert beneficial effects when administered intraperitoneally. CONCLUSIONS AND IMPLICATIONS: Oral but not intraperitoneal alendronate significantly protected the colon in experimental rat colitis. Inflammatory bowel disease patients might benefit from exposure to oral alendronate.


Assuntos
Alendronato/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Colite/prevenção & controle , Colo/efeitos dos fármacos , Administração Oral , Alendronato/administração & dosagem , Animais , Anti-Inflamatórios/administração & dosagem , Peso Corporal/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Quimiocina CCL2/genética , Colite/induzido quimicamente , Colo/metabolismo , Colo/patologia , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/uso terapêutico , Expressão Gênica/efeitos dos fármacos , Injeções Intraperitoneais , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1beta/genética , Ratos , Ratos Wistar , Sulfassalazina/administração & dosagem , Sulfassalazina/uso terapêutico , Resultado do Tratamento , Ácido Trinitrobenzenossulfônico
15.
FEBS Lett ; 542(1-3): 84-8, 2003 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-12729903

RESUMO

Oral administration of sodium tungstate is an effective treatment for diabetes in animal models. We examined the effects of 6 weeks of oral administration of tungstate on glucose transporters (GLUT) in streptozotocin-induced diabetic rat diaphragm. Diabetes decreased GLUT4 expression while tungstate treatment normalized not only GLUT4 protein but also GLUT4 mRNA in the diabetic rats. Furthermore, treatment increased GLUT4 protein in plasma and internal membranes, suggesting a stimulation of its translocation to the plasma membrane. Tungstate had no effect on healthy animals. There were no differences in the total amount of GLUT1 transporter in any group. We conclude that the normoglycemic effect of tungstate may be partly due to a normalization of the levels and subcellular localization of GLUT4, which should result in an increase in muscle glucose uptake.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diafragma/efeitos dos fármacos , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas Musculares , Compostos de Tungstênio/farmacologia , Animais , Glicemia/análise , Membrana Celular/química , Diabetes Mellitus Experimental/diagnóstico , Diafragma/metabolismo , Feminino , Transportador de Glucose Tipo 1 , Transportador de Glucose Tipo 4 , Proteínas de Transporte de Monossacarídeos/análise , Proteínas de Transporte de Monossacarídeos/genética , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar
16.
Biochem Biophys Res Commun ; 283(4): 782-4, 2001 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-11350052

RESUMO

Follicular fluid is made of both follicular cell-secreted molecules as well as blood infiltration into the follicle. Sperm-attracting activity has been associated to column-filtered proteins as well as to progesterone. Here we report the initial characterization of a protein with this activity. Follicular fluid was collected from preovulatory follicles in freshly obtained ovaries from a local slaughterhouse. Fluid was cleared from cells and fractionated by size exclusion chromatography and polyacrylamide gel electrophoresis. For gamete interaction, sperm were allowed to swim in an agarose-covered slide designed to separate two wells by a rod in a fixed pattern. At each well, a semisolid agarose solution containing either the attractant with oocytes or control solution in one end, whereas capacitated boar sperm was at the opposite well. Sperm bound to oocytes were evaluated under phase contrast microscopy. Results show that fluid from preovulatory follicles have a sperm attracting activity and that this activity can be associated with an 8600 Dalton protein that at the N-terminal end exhibit close relation to Apoliprotein B2.


Assuntos
Líquido Folicular/fisiologia , Proteínas/fisiologia , Espermatozoides/fisiologia , Animais , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Feminino , Líquido Folicular/metabolismo , Masculino , Proteínas/química , Proteínas/isolamento & purificação , Suínos
17.
Arch Androl ; 46(1): 15-20, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11204612

RESUMO

Some plants have more than the common utility value, as is the case of some members of the Bursera species such as the Mexican copal, a plant used for worship. Water extracts of several plants have vaginal contraceptive properties. The authors evaluated the sperm agglutinating activity of two Bursera species on human and boar sperm. Extracts from stems and leaves were obtained. Capacitated sperm samples were used in all cases. There were different agglutinating capacities, which were not observed in the vehicle-only samples. The most frequent sperm agglutination response was that involving the heads. Agglutinating activity was higher from stem- than leaf-derived extracts. The results indicate that proteins present in the extracts are responsible for the aggregation of sperm heads.


Assuntos
Extratos Vegetais/farmacologia , Rosales/química , Aglutinação Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , América Central , Anticoncepcionais Masculinos/farmacologia , Humanos , Técnicas In Vitro , Masculino , Suínos
18.
Dig Dis Sci ; 45(10): 2044-50, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11117581

RESUMO

The aim of the present study was to evaluate the influence of severe protein-energy malnutrition on the antioxidant defense system in the small and large intestine in rats at weaning. Chronic diarrhea and the subsequent malnutrition were induced by oral intake of a lactose-enriched diet. Twenty rats were weaned at 21 days of age, and the control group was fed a semipurified synthetic diet for two weeks. The malnourished group was fed the same diet but carbohydrates were replaced by lactose, and they developed diarrhea one day after. Rats were killed, and macroscopic and histological features were analyzed, DNA content was measured, and alkaline phosphatase, myeloperoxidase, and gamma-glutamyltranspeptidase activities were determined to assess the degree of intestinal injury. Glutathione levels as well as the activities of intestinal glutathione transferase, glutathione reductase, total glutathione peroxidase, selenium-dependent glutathione peroxidase, superoxide dismutase, and catalase were measured to study the antioxidant defense system. Malnourished rats showed loss of body weight and an increase in length and weight in jejunum and ileum, while no significant changes were observed in colon. Epithelial cells showed fewer and shorter microvilli, larger mitochondria with low inner density and loss of cristae, dilated endoplasmic reticulum, and Golgi apparatus. The protein-to-DNA ratio was higher in the jejunum, ileum, and colon of malnourished rats. Glutathione levels decreased 40% in jejunum and 50% in colon of malnourished rats. A 40-50% decrease in the activity of all the enzymes of the antioxidant defense system was observed in the jejunum and ileum of malnourished rats, while only catalase and glutathione transferase activities decreased 50% in colon. These results suggest that early chronic diarrhea and severe protein-energy malnutrition impair the antioxidant defense system in both the small and large intestine, which may have a role in the pathogenesis and maintenance of the vicious circle of malabsorption-diarrhea-malnutrition in infancy.


Assuntos
Antioxidantes/metabolismo , Diarreia/fisiopatologia , Animais , Doença Crônica , Diarreia/patologia , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Masculino , Microscopia Eletrônica , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Desmame
19.
Dig Dis Sci ; 45(9): 1820-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11052326

RESUMO

Increasing attention has been given recently to the role of free radicals in the pathogenesis of ulcerative colitis, since the inflamed intestine is exposed to oxidative stress generated by infiltrating macrophages and neutrophils within the lamina propia. The overall goal of this study was to evaluate whether experimental ulcerative colitis induces significant changes in the antioxidant defense system in an experimental model induced by the intrarectal administration of 2,4,6-trinitrobenzenesulfonic acid. Twenty rats were treated with 80 mg/kg body weight of trinitrobenzenesulfonic acid and 20 with the same volume of 0.9% NaCl. Rats were killed at one and two weeks after treatment to evaluate colon damage by light and electron transmission microscopy. The degree of tissue injury and inflammation was determined by measuring alkaline phosphatase, gamma-glutamyltranspeptidase, and myeloperoxidase activities and prostaglandin E2 and leukotriene B4. Glutathione levels and the activity of the enzymes of the antioxidant defense system were determined. Enzymatic markers of colon injury showed higher activities in rats with ulcerative colitis. Concentrations of prostaglandin E2 and leukotriene B4 were higher in the groups treated for one week with trinitrobenzenesulfonic acid and markers decreased after two weeks of treatment. All antioxidant enzyme activities were higher at one and two weeks after treatment; however, a significant decrease in total glutathione content was also observed. In conclusion, ulcerative colitis induced by trinitrobenzenesulfonic acid damages the intestinal mucosa and is accompanied by a shift in the antioxidant enzyme activities, and low levels of glutathione. This deficiency in glutathione could be a target for new therapies to treat ulcerative colitis.


Assuntos
Antioxidantes/metabolismo , Colite Ulcerativa/metabolismo , Colo/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Catalase/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Colo/patologia , Dinoprostona/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Mucosa Intestinal/enzimologia , Mucosa Intestinal/patologia , Leucotrieno B4/metabolismo , Masculino , Peroxidase/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , gama-Glutamiltransferase/metabolismo
20.
Lipids ; 35(6): 587-93, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10901418

RESUMO

We observed and compared alterations in 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase at the transcriptional level in unsynchronized, three-passage cultures of smooth-muscle cells from the aorta of chicks fed on a control diet (C-SMC) and those of chicks fed on a similar diet plus cholesterol (Ch-SMC). Alterations in reductase mRNA concentrations in senescent cultures were much lower. We used a modification of the competitive (c) reverse transcription polymerase chain reaction method, using a Thermus thermophilus DNA polymerase (Tth pol) to quantify the very scarce species of HMG-CoA reductase mRNA in samples of cytoplasmic SMC mRNA. We cloned and sequenced a 199 bp cDNA fragment of chicken HMG-CoA reductase, which encoded a region of 66 amino acids belonging to the catalytic domain of the enzyme. HMG-CoA reductase mRNA concentrations from young C-SMC cultures rose 3.89-fold 4 h after the change of medium and returned to base levels between 8 to 12 h afterward. Concentrations in Ch-SMC cultures increased less (2.36-fold) 8 h after the change to fresh medium. Increases in reductase mRNA in senescent cultures of Ch-SMC and C-SMC measured under similar conditions were only 1.28- and 1.39-fold, respectively.


Assuntos
Aorta/enzimologia , Hidroximetilglutaril-CoA Redutases/genética , Músculo Liso Vascular/enzimologia , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Animais , Aorta/citologia , Sequência de Bases , Células Cultivadas , Galinhas , Primers do DNA , Hidroximetilglutaril-CoA Redutases/química , Masculino , Dados de Sequência Molecular , Músculo Liso Vascular/citologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
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