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2.
Animal ; 11(9): 1626-1635, 2017 Sep.
Article de Anglais | MEDLINE | ID: mdl-28115030

RÉSUMÉ

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 In total, 32 suckling kids were withdrawn from each farm, transported by road for 2 or 6 h, and then slaughtered.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.


Sujet(s)
Bien-être animal , Animaux allaités/physiologie , Capra/physiologie , Viande rouge/normes , Stress physiologique , Abattoirs , Agriculture , Animaux , Couleur , Creatine kinase/sang , Fermes , Hydrocortisone/sang , Concentration en ions d'hydrogène , Mâle , Phénotype , Modifications postmortem , Facteurs temps , Transports
3.
Actas Dermosifiliogr ; 107(4): e19-22, 2016 May.
Article de Anglais, Espagnol | MEDLINE | ID: mdl-26706712

RÉSUMÉ

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.


Sujet(s)
Sarcome de Kaposi/imagerie diagnostique , Tumeurs cutanées/imagerie diagnostique , Échographie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle
5.
Environ Toxicol Pharmacol ; 36(1): 125-34, 2013 Jul.
Article de Anglais | MEDLINE | ID: mdl-23603465

RÉSUMÉ

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.


Sujet(s)
Sulfate de cuivre/toxicité , Cyprinodontiformes/métabolisme , Polluants chimiques de l'eau/toxicité , Animaux , Catalase/métabolisme , Sulfate de cuivre/pharmacocinétique , Femelle , Protéines de poisson/métabolisme , Branchies/métabolisme , Glutathione peroxidase/métabolisme , Glutathione reductase/métabolisme , Glutathione transferase/métabolisme , Métabolisme lipidique/effets des médicaments et des substances chimiques , Peroxydation lipidique/effets des médicaments et des substances chimiques , Mâle , Métallothionéine/métabolisme , Superoxide dismutase/métabolisme , Polluants chimiques de l'eau/pharmacocinétique
6.
Pharmacol Res ; 66(2): 144-53, 2012 Aug.
Article de Anglais | MEDLINE | ID: mdl-22569414

RÉSUMÉ

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.


Sujet(s)
Phosphatase alcaline/usage thérapeutique , Translocation bactérienne/effets des médicaments et des substances chimiques , Colite/traitement médicamenteux , Phosphatase alcaline/génétique , Phosphatase alcaline/métabolisme , Phosphatase alcaline/pharmacologie , Animaux , Colite/induit chimiquement , Colite/enzymologie , ADN bactérien/analyse , Sulfate dextran , Modèles animaux de maladie humaine , Fèces/enzymologie , Femelle , Régulation de l'expression des gènes codant pour des enzymes/effets des médicaments et des substances chimiques , Foie/microbiologie , Souris , Souris de lignée C57BL , Souris SCID , Myeloperoxidase/métabolisme , Rats , Rat Wistar , Acide 2,4,6-trinitro-benzènesulfonique
7.
Nutr Hosp ; 27(5): 1626-30, 2012.
Article de Anglais | MEDLINE | ID: mdl-23478715

RÉSUMÉ

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.


Sujet(s)
Composition corporelle/physiologie , Obésité/métabolisme , Absorptiométrie photonique , Tissu adipeux/anatomopathologie , Adulte , Anatomie en coupes transversales , Indice de masse corporelle , Impédance électrique , Femelle , Humains , Mâle , Adulte d'âge moyen , Obésité/anatomopathologie , Reproductibilité des résultats
8.
Crit Rev Food Sci Nutr ; 51(4): 331-62, 2011 Apr.
Article de Anglais | MEDLINE | ID: mdl-21432698

RÉSUMÉ

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.


Sujet(s)
Flavonoïdes/administration et posologie , Inflammation/prévention et contrôle , Phénols/administration et posologie , Animaux , Régime alimentaire , Flavonoïdes/métabolisme , Humains , Inflammation/diétothérapie , Inflammation/traitement médicamenteux , Phénols/métabolisme , Polyphénols
9.
Br J Pharmacol ; 160(7): 1714-26, 2010 Aug.
Article de Anglais | MEDLINE | ID: mdl-20649574

RÉSUMÉ

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.


Sujet(s)
Inhibiteurs de la cyclooxygénase 2/pharmacologie , Cyclooxygenase 2/métabolisme , Cellules épithéliales/effets des médicaments et des substances chimiques , Flavonoïdes/pharmacologie , Muqueuse intestinale/effets des médicaments et des substances chimiques , Facteur de transcription NF-kappa B/antagonistes et inhibiteurs , Animaux , Technique de Western , Lignée cellulaire , Noyau de la cellule/métabolisme , Survie cellulaire/effets des médicaments et des substances chimiques , Cyclooxygenase 2/biosynthèse , Inhibiteurs de la cyclooxygénase 2/composition chimique , Relation dose-effet des médicaments , Cellules épithéliales/enzymologie , Cellules épithéliales/immunologie , Flavonoïdes/composition chimique , Muqueuse intestinale/cytologie , Muqueuse intestinale/enzymologie , Muqueuse intestinale/immunologie , L-Lactate dehydrogenase/métabolisme , Lipopolysaccharides/pharmacologie , Luciferases/génétique , Structure moléculaire , Facteur de transcription NF-kappa B/génétique , Facteur de transcription NF-kappa B/métabolisme , Plasmides , Transport des protéines , Rats
10.
Clin Microbiol Infect ; 15(5): 443-53, 2009 May.
Article de Anglais | MEDLINE | ID: mdl-19368547

RÉSUMÉ

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.


Sujet(s)
Antigènes bactériens/urine , Protéines bactériennes/urine , Infections à pneumocoques/diagnostic , Streptococcus pneumoniae/immunologie , Urine/microbiologie , Séquence d'acides aminés , Animaux , Technique de Western/méthodes , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Données de séquences moléculaires , Lapins , Sensibilité et spécificité , Alignement de séquences
11.
Br J Pharmacol ; 154(4): 825-32, 2008 Jun.
Article de Anglais | MEDLINE | ID: mdl-18536735

RÉSUMÉ

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.


Sujet(s)
Anti-inflammatoires/pharmacologie , Régulation négative/effets des médicaments et des substances chimiques , Glycopeptides/pharmacologie , Iléite/traitement médicamenteux , Administration par voie orale , Animaux , Bovins , Modèles animaux de maladie humaine , Femelle , Iléite/physiopathologie , Interleukine-17/métabolisme , Macrophages/effets des médicaments et des substances chimiques , Macrophages/métabolisme , Mésalazine/pharmacologie , Rats , Rat Wistar , Lymphocytes T auxiliaires/effets des médicaments et des substances chimiques , Lymphocytes T auxiliaires/métabolisme , Lymphocytes T régulateurs/effets des médicaments et des substances chimiques , Lymphocytes T régulateurs/métabolisme , Acide 2,4,6-trinitro-benzènesulfonique
12.
Br J Pharmacol ; 151(2): 206-15, 2007 May.
Article de Anglais | MEDLINE | ID: mdl-17375077

RÉSUMÉ

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.


Sujet(s)
Alendronate/usage thérapeutique , Anti-inflammatoires/usage thérapeutique , Colite/prévention et contrôle , Côlon/effets des médicaments et des substances chimiques , Administration par voie orale , Alendronate/administration et posologie , Animaux , Anti-inflammatoires/administration et posologie , Poids/effets des médicaments et des substances chimiques , Agents de maintien de la densité osseuse/administration et posologie , Agents de maintien de la densité osseuse/usage thérapeutique , Chimiokine CCL2/génétique , Colite/induit chimiquement , Côlon/métabolisme , Côlon/anatomopathologie , Diphosphonates/administration et posologie , Diphosphonates/usage thérapeutique , Relation dose-effet des médicaments , Femelle , Agents gastro-intestinaux/administration et posologie , Agents gastro-intestinaux/usage thérapeutique , Expression des gènes/effets des médicaments et des substances chimiques , Injections péritoneales , Antagoniste du récepteur à l'interleukine-1/génétique , Interleukine-1 bêta/génétique , Rats , Rat Wistar , Sulfasalazine/administration et posologie , Sulfasalazine/usage thérapeutique , Résultat thérapeutique , Acide 2,4,6-trinitro-benzènesulfonique
15.
FEBS Lett ; 542(1-3): 84-8, 2003 May 08.
Article de Anglais | MEDLINE | ID: mdl-12729903

RÉSUMÉ

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.


Sujet(s)
Diabète expérimental/métabolisme , Muscle diaphragme/effets des médicaments et des substances chimiques , Transporteurs de monosaccharides/métabolisme , Protéines du muscle , Composés du tungstène/pharmacologie , Animaux , Glycémie/analyse , Membrane cellulaire/composition chimique , Diabète expérimental/diagnostic , Muscle diaphragme/métabolisme , Femelle , Transporteur de glucose de type 1 , Transporteur de glucose de type 4 , Transporteurs de monosaccharides/analyse , Transporteurs de monosaccharides/génétique , ARN messager/biosynthèse , Rats , Rat Wistar
16.
Biochem Biophys Res Commun ; 283(4): 782-4, 2001 May 18.
Article de Anglais | MEDLINE | ID: mdl-11350052

RÉSUMÉ

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.


Sujet(s)
Liquide folliculaire/physiologie , Protéines/physiologie , Spermatozoïdes/physiologie , Animaux , Chromatographie sur gel , Électrophorèse sur gel de polyacrylamide , Femelle , Liquide folliculaire/métabolisme , Mâle , Protéines/composition chimique , Protéines/isolement et purification , Suidae
17.
Arch Androl ; 46(1): 15-20, 2001.
Article de Anglais | MEDLINE | ID: mdl-11204612

RÉSUMÉ

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.


Sujet(s)
Extraits de plantes/pharmacologie , Rosales/composition chimique , Agglutination des spermatozoïdes/effets des médicaments et des substances chimiques , Spermatozoïdes/effets des médicaments et des substances chimiques , Animaux , Amérique centrale , Contraceptifs masculins/pharmacologie , Humains , Techniques in vitro , Mâle , Suidae
18.
Dig Dis Sci ; 45(10): 2044-50, 2000 Oct.
Article de Anglais | MEDLINE | ID: mdl-11117581

RÉSUMÉ

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.


Sujet(s)
Antioxydants/métabolisme , Diarrhée/physiopathologie , Animaux , Maladie chronique , Diarrhée/anatomopathologie , Muqueuse intestinale/anatomopathologie , Muqueuse intestinale/physiopathologie , Mâle , Microscopie électronique , Rats , Rat Wistar , Espèces réactives de l'oxygène/métabolisme , Sevrage
19.
Dig Dis Sci ; 45(9): 1820-7, 2000 Sep.
Article de Anglais | MEDLINE | ID: mdl-11052326

RÉSUMÉ

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.


Sujet(s)
Antioxydants/métabolisme , Rectocolite hémorragique/métabolisme , Côlon/métabolisme , Phosphatase alcaline/métabolisme , Animaux , Catalase/métabolisme , Rectocolite hémorragique/induit chimiquement , Rectocolite hémorragique/anatomopathologie , Côlon/anatomopathologie , Dinoprostone/métabolisme , Glutathion/métabolisme , Glutathione peroxidase/métabolisme , Glutathione reductase/métabolisme , Glutathione transferase/métabolisme , Muqueuse intestinale/enzymologie , Muqueuse intestinale/anatomopathologie , Leucotriène B4/métabolisme , Mâle , Myeloperoxidase/métabolisme , Rats , Rat Wistar , Superoxide dismutase/métabolisme , gamma-Glutamyltransferase/métabolisme
20.
Lipids ; 35(6): 587-93, 2000 Jun.
Article de Anglais | MEDLINE | ID: mdl-10901418

RÉSUMÉ

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.


Sujet(s)
Aorte/enzymologie , Hydroxymethylglutaryl-CoA reductases/génétique , Muscles lisses vasculaires/enzymologie , ARN messager/métabolisme , Séquence d'acides aminés , Animaux , Aorte/cytologie , Séquence nucléotidique , Cellules cultivées , Poulets , Amorces ADN , Hydroxymethylglutaryl-CoA reductases/composition chimique , Mâle , Données de séquences moléculaires , Muscles lisses vasculaires/cytologie , ARN messager/génétique , RT-PCR , Similitude de séquences d'acides aminés
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