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1.
J Struct Biol ; 208(2): 174-181, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31476367

RESUMEN

Assessing the internal morphology of Caenorhabditis elegans by a topographical technique like atomic force microscopy (AFM) is a challenging process. As a prerequisite for a successful image acquisition, direct contact between the structure of interest and the AFM probe needs to be established. To gain this insight into the morphology of cuticle and intestine in C. elegans before and after treatment with a tannin-enriched hydro-ethanolic extract from Combretum mucronatum, we developed an approach based on polyethylene glycol embedding, ultra-sectioning, de-embedding and hexamethyldisilazane-dehydration prior to measuring in ambient conditions by intermittent contact mode AFM. The used experimental protocol allowed a facile and fast insight into the ultrastructure of treated versus untreated C. elegans individuals, directly leading to the identification of treatment-associated morphological alterations in the cuticle but not the intestine of C. elegans. Additionally, the presented ultra-microtomy based protocol could allow future insight into virtually any tissue or organism by AFM.


Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Combretum/química , Intestinos/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Antihelmínticos/química , Antihelmínticos/farmacología , Caenorhabditis elegans/ultraestructura , Intestinos/ultraestructura , Microscopía de Fuerza Atómica , Extractos Vegetales/química , Taninos/farmacología
2.
Microb Pathog ; 114: 255-263, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29174701

RESUMEN

The aim of this study is to select and isolate autochthonous bacteria with probiotic potential for use in a supplemented diet for bullfrog tadpoles, Lithobates catesbeianus. A total of 20 strains of lactic acid bacteria were isolated. Nine out of these were used in the following in vitro assays: antagonism against pathogenic bacteria (ANT), antimicrobial activity from extracellular compounds (MIC), tolerance to bile salts (TBS), pH reduction, protease production, sensitivity to antimicrobial tetracycline, cell viability, growth rate and doubling time. Using these data was defined an ideotype (ideal strain) based on the best results. Distances were estimated with the Mahalanobis (D2) test, and the best candidates, presenting the shortest ideotype distances, were considered to be used. The best strain was found to be Lactobacillus plantarum because it presented 10.00 ± 0.50 mm of ANT against Aeromonas hydrophila, 3.99 ± 0.01 of MIC independent of pathogenic bacteria, 85.07 ± 0.01 of TBS, 4.20 ± 0.02 of final pH, 17.67 ± 1.15 of protease production, 13.50 ± 2.00 sensitivity to antimicrobial tetracycline, 9.36 ± 0.04 of cell viability, 0.20 ± 0.00 of growth rate and 3.46 ± 0.00 doubling time. Therefore this probiotic candidate was then supplemented (2.045 ± 1.07 × 107 colony forming unities. g-1) into the diets of bullfrog tadpoles for a period of 42 days. At the end of the trial, samples of blood and intestines were collected to verify the haematological alterations and the intestinal morphology using transmission and scanning electron microscopy. Tadpoles fed the supplemented diet showed successful lactic acid bacterium colonisation, an increased number of circulating thrombocytes, monocytes, eosinophil and LG-PAS+ and also an increase in the length and density of intestinal microvilli. This study shows the feasibility of using probiotics isolated from farmed bullfrogs as a supplement in the diets of tadpoles, providing a promising alternative for modulating the health of these animals.


Asunto(s)
Larva/metabolismo , Probióticos/administración & dosificación , Rana catesbeiana/microbiología , Alimentación Animal/análisis , Animales , Suplementos Dietéticos/análisis , Hematología , Intestinos/crecimiento & desarrollo , Intestinos/microbiología , Intestinos/ultraestructura , Lactobacillus/clasificación , Lactobacillus/genética , Lactobacillus/crecimiento & desarrollo , Lactobacillus/aislamiento & purificación , Larva/crecimiento & desarrollo , Larva/microbiología , Larva/ultraestructura , Microscopía Electrónica , Rana catesbeiana/sangre , Rana catesbeiana/crecimiento & desarrollo
3.
Sci Rep ; 7(1): 5512, 2017 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-28717234

RESUMEN

In the present study, we explored whether dietary lipid content influences the gut microbiome in adult zebrafish. Diets containing three different lipid levels (high [HFD], medium [MFD], and low [LFD]) were administered with or without the supplementation of Lactobacillus rhamnosus (P) to zebrafish in order to explore how the dietary lipid content may influence the gut microbiome. Dietary lipid content shifted the gut microbiome structure. The addition of L. rhamnosus in the diets, induced transcriptional reduction of orexigenic genes, upregulation of anorexigenic genes, and transcriptional decrease of genes involved in cholesterol and triglyceride (TAG) metabolism, concomitantly with lower content of cholesterol and TAG. Probiotic feeding also decreased nesfatin-1 peptide in HFD-P and attenuated weight gain in HFD-P and MFD-P fed zebrafish, but not in LFD-P group. Intestinal ultrastructure was not affected by dietary fat level or probiotic inclusion. In conclusion, these findings underline the role of fat content in the diet in altering gut microbiota community by shifting phylotype composition and highlight the potential of probiotics to attenuate high-fat diet-related metabolic disorder.


Asunto(s)
Grasas de la Dieta , Microbioma Gastrointestinal/efectos de los fármacos , Lacticaseibacillus rhamnosus/fisiología , Obesidad/prevención & control , Probióticos/farmacología , Pez Cebra/metabolismo , Animales , Apetito/efectos de los fármacos , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Colesterol/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Dieta Alta en Grasa , Femenino , Intestinos/patología , Intestinos/ultraestructura , Gotas Lipídicas/metabolismo , Gotas Lipídicas/ultraestructura , Masculino , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Nucleobindinas , Obesidad/veterinaria , Análisis de Componente Principal , Probióticos/uso terapéutico , Triglicéridos/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
4.
Biol Res Nurs ; 17(1): 78-86, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25504953

RESUMEN

Mechanical enemas can lead to intestinal mucosal injuries and bowel barrier damage, presenting as electrolyte disturbances and functional intestinal disorders. Most researchers believe that the mechanism of injury is related to osmolality, volume and temperature of the solution, infusion pressure, and the composition of the enema tube. We hypothesized that the pH of the enema solution may also contribute to intestinal damage. We administered enema solutions--normal saline, soapsuds, or vinegar (neutral, alkaline, or acidic solutions, respectively)--to three groups of rabbits (n = 20 per group). The solutions were standardized for volume and temperature and the soapsuds and vinegar solutions were adjusted to be isotonic with normal saline or deionized water. We also included a control group (n = 20) in which the enema tubes were inserted but no solution was administered. We biopsied 3 sites (rectum and distal and proximal colon). Damage to intestinal mucosa was observed by light microscopy and transmission electron microscopy. In order to explore the detection of damage using noninvasive methods, cyclooxygenase (COX)-2 gene expression was measured in the exfoliated cells gathered from postenema defecation. Epithelial loss, inflammatory reaction, and cellular microstructure damage was increased in the vinegar and soapsuds groups. Also, exfoliated cells in these groups had higher COX-2 expression than the normal saline group. The acidic and alkaline enema solutions thus caused more severe damage to the intestinal mucosa compared to the neutral liquid, supporting our hypothesis. Further, the detection of COX-2 expression shows promise as a noninvasive method for estimating enema-induced damage.


Asunto(s)
Enema/efectos adversos , Concentración de Iones de Hidrógeno , Intestinos/lesiones , Animales , Secuencia de Bases , Ciclooxigenasa 2/genética , Cartilla de ADN , Intestinos/enzimología , Intestinos/ultraestructura , Microscopía Electrónica de Transmisión , ARN Mensajero/genética , Conejos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Soluciones
5.
Br Poult Sci ; 55(5): 619-27, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25088948

RESUMEN

To investigate the effect of replacing maize with whole-grain paddy rice (WPR) in broiler chicken diets, with or without enzyme addition, on growth performance and histological structures of the intestinal villi, 14-d-old Marshall Chunky male chicks were divided into 4 groups with 4 replicates of 4 chicks each. The experimental diets containing different concentrations of WPR were as follows: (1) 0 g/kg (Control); (2) 141.5 g/kg, grower, and 125.0 g/kg, finisher (25WPR); (3) 283.0 g/kg, grower, and 250.0 g/kg, finisher (50WPR); (4) 283.0 g/kg, grower, and 250.0 g/kg, finisher, and enzyme supplementation (50WPR + enzyme). All diets were formulated to be isocaloric and isonitrogenous and provided ad libitum for 35 d. There were no differences among the diets on the growth performance and digestive organ size. The villus height and cell mitosis number of all intestinal segments did not change in any treatment. The ileal villus area, duodenal cell area, duodenal and jejunal goblet cell number in the 50WPR group increased significantly relative to the control but not when enzyme was included. In the scanning electron microscope results, all experimental groups showed clear protuberant cells and cell clusters on the villus apical surface of the duodenum. In the jejunum, cell clusters and areas having cells with no microvilli were frequently found in both the 50WPR and 50WPR + enzyme groups. In conclusion, broilers fed on diets replacing maize with WPR showed hypertrophied villi of duodenum and ileum and epithelial cells in duodenum and jejunum, especially in the 50WPR group, without negatively affecting growth performance. These findings suggest that WPR can replace maize up to a level of 50% (283.0 g/kg, starter, and 250.0 g/kg, finisher) in broiler diets without enzyme supplementation. However, further studies are needed to improve our knowledge of the influence of WPR on higher numbers of birds.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Pollos/metabolismo , Dieta/veterinaria , Enzimas/metabolismo , Oryza/química , Zea mays/química , Alimentación Animal/análisis , Animales , Pollos/anatomía & histología , Pollos/crecimiento & desarrollo , Suplementos Dietéticos/análisis , Digestión , Enzimas/administración & dosificación , Intestinos/anatomía & histología , Intestinos/efectos de los fármacos , Intestinos/ultraestructura , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Tamaño de los Órganos , Distribución Aleatoria , Estómago/anatomía & histología , Estómago/efectos de los fármacos , Estómago/ultraestructura
6.
Br J Nutr ; 112(1): 15-29, 2014 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-24774835

RESUMEN

The aim of the present study was to investigate the effects of different dietary sustained-release microencapsulated sodium butyrate (MSB) products (0 (non-supplement), 1·5 and 3·0 h) for a control or oxidised soyabean oil (SBO) diet on fish production, intestinal mucosal condition, immunity and intestinal bacteria in juvenile common carp (Cyprinus carpio). Dietary MSB increased weight gain and reduced the feed conversion ratio within the control and oxidised SBO groups. Gut mucosa was damaged in the oxidised SBO group fed without MSB, in contrast to a normal appearance found in fish fed the MSB1·5 and MSB3·0 diets in the oxidised SBO group. Microvillus density increased in fish fed the MSB1·5 and MSB3·0 diets in the oxidised SBO group (P< 0·001); however, microvillus density was affected by the different pre-fed diets in the midgut (P< 0·001) and by the different sustained-release times of MSB in the distal gut (DG) (P= 0·003). The interaction between the pre-fed diets and the sustained-release times of dietary MSB was significant for the relative gene expression levels of gut heat shock protein-70 (HSP70), pro-inflammatory cytokines (IL-1ß and TNF-α) and anti-inflammatory cytokines (transforming growth factor-ß) within each gut segment, except for HSP70 in the DG and IL-1ß in the foregut. Modulation of adherent bacterial communities within each gut segment investigated was not obvious when the common carp were fed the diets with MSB, as similarity coefficients of >0·79 were observed. These results indicated that MSB can be used as a dietary supplement to repair or prevent intestinal damage in carp fed oxidised SBO.


Asunto(s)
Antioxidantes/metabolismo , Adhesión Bacteriana , Ácido Butírico/metabolismo , Carpas/crecimiento & desarrollo , Dieta/veterinaria , Inmunidad Mucosa , Mucosa Intestinal/crecimiento & desarrollo , Animales , Antioxidantes/química , Acuicultura , Ácido Butírico/química , Carpas/inmunología , Carpas/metabolismo , Carpas/microbiología , China , Citocinas/genética , Citocinas/metabolismo , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Regulación del Desarrollo de la Expresión Génica , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Gramnegativas/inmunología , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/crecimiento & desarrollo , Bacterias Grampositivas/inmunología , Bacterias Grampositivas/aislamiento & purificación , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Mucosa Intestinal/ultraestructura , Intestinos/crecimiento & desarrollo , Intestinos/inmunología , Intestinos/microbiología , Intestinos/ultraestructura , Microvellosidades/inmunología , Microvellosidades/microbiología , Microvellosidades/ultraestructura , Oxidación-Reducción , Estrés Oxidativo , Solubilidad , Aceite de Soja/efectos adversos , Aceite de Soja/antagonistas & inhibidores , Aceite de Soja/química
7.
J Anim Physiol Anim Nutr (Berl) ; 98(4): 636-42, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23859084

RESUMEN

We investigated mannanase-hydrolysed copra meal (MCM), which contains ß-1,4-mannobiose (MNB), for its capacity to improve growth performance and activate intestinal villus function. Seven-day-old chicks were separated into four flocks with an equal mean body weight and then fed a basal diet (control) or a diet supplemented with 0.02% or 0.1% MCM. After 7 weeks, the feed intake and body weight were determined and then used to calculate the feed efficiency (FE). Moreover, the intestinal segments were examined by light microscopy and scanning electron microscopy (SEM) for cellular and morphological changes in the villus. Although feed intake was not significantly different among the experimental groups, the body weight gain and FE were significantly higher in the 0.1% MCM group than in the control group (p < 0.05), while feed intake tended to be higher in the 0.02% and 0.1% MCM groups. The cellular area of the ileum was significantly higher in the 0.02% and 0.1% groups in relation to that in the control group (p < 0.05). Furthermore, the cellular area of the duodenum and the jejunum tended to be higher in the 0.02% and 0.1% MCM groups. For the correlation analysis, a significant correlation was observed between the dosage of MCM and the cell area of the duodenum, jejunum and ileum. Moreover, the number of mitotic cells was higher in the 0.1% MCM group. As shown by SEM, the cells at the villi tips were protuberant in appearance in the 0.02% and 0.1% MCM treatments when compared with the relatively flat cells of the control. On the duodenal villus surface of the 0.1% MCM group, some cells devoid of microvilli were observed, suggesting that the increased protuberance of these cells represents increased absorption activity. Although intestinal villus height and area did not significantly differ among groups, the levels of these parameters tended to increase in the experimental groups relative to the control. The present morphological findings reveal that MNB might be effective for activating intestinal absorptive function, and that the functional activation promotes the growth of the chickens.


Asunto(s)
Alimentación Animal/análisis , Pollos/anatomía & histología , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Intestinos/ultraestructura , 6-Fitasa/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Carbohidratos de la Dieta , Masculino , Mananos/metabolismo
8.
J Appl Microbiol ; 115(5): 1091-106, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23889777

RESUMEN

AIM: To assess the effects of dietary Saccharomyces cerevisiae ß-(1,3)(1,6)-D-glucan supplementation (MacroGard(®)) on mirror carp (Cyprinus carpio L.) intestinal microbiota and ultrastructure of the enterocyte apical brush border. METHODS AND RESULTS: Carp were fed either a control diet or diets supplemented with 0.1, 1 or 2% w/w MacroGard(®). Culture-dependent microbiology revealed that aerobic heterotrophic bacterial levels were unaffected by dietary MacroGard(®) after 2 and 4 weeks. No effects were observed on the allochthonous lactic acid bacteria (LAB) populations at either time point; however, reduced autochthonous LAB populations were observed at week 4. PCR-DGGE confirmed these findings through a reduction in the abundance of autochthonous Lactococcus sp. and Vagococcus sp. in MacroGard(®)--fed fish compared with the control-fed fish. Overall, sequence analysis detected microbiota belonging to the phyla Proteobacteria, Firmicutes, Fusobacteria and unidentified uncultured bacteria. DGGE analyses also revealed that dietary MacroGard(®) reduced the number of observed taxonomical units (OTUs) and the species richness of the allochthonous microbiota after 2 weeks, but not after 4 weeks. In contrast, dietary MacroGard(®) reduced the number of OTUs, the species richness and diversity of the autochthonous microbiota after 2 weeks, and those parameters remained reduced after 4 weeks. Transmission electron microscopy revealed that intestinal microvilli length and density were significantly increased after 4 weeks in fish fed diets supplemented with 1% MacroGard(®). CONCLUSIONS: This study indicates that dietary MacroGard(®) supplementation modulates intestinal microbial communities of mirror carp and influences the morphology of the apical brush border. SIGNIFICANCE AND IMPACT OF THE STUDY: To the authors' knowledge, this is the first study to investigate the effects of ß-(1,3)(1,6)-D-glucans on fish gut microbial communities, using culture-independent methods, and the ultrastructure of the apical brush border of the enterocytes in fish. This prebiotic-type effect may help to explain the mechanisms in which ß-glucans provide benefits when fed to fish.


Asunto(s)
Alimentación Animal , Carpas/microbiología , Glucanos/farmacología , Intestinos/microbiología , Intestinos/ultraestructura , Microbiota/efectos de los fármacos , Animales , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Electroforesis en Gel de Gradiente Desnaturalizante , Suplementos Dietéticos/análisis , Microscopía Electrónica de Transmisión , Microvellosidades/ultraestructura , Reacción en Cadena de la Polimerasa , Prebióticos
9.
Poult Sci ; 92(4): 956-65, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23472019

RESUMEN

The recent ban on the use of antibiotics as a feed additive has led to the search for alternative sources of antibiotics in the feed industry. Presently, probiotics are considered as a potential substitute for antibiotic as a live biotherapeutic agent to improve animal health and performance. Accordingly, study was focused on evaluating the effect of Saccharomyces boulardii (Sb) and Bacillus subtilis B10 (Bs) on ultrastructure modulation and mucosal immunity development in broiler chickens. A total of three hundred 1-d-old Sanhuang broilers (a Chinese cross breed) were randomized into 3 groups, each group with 5 replications (n = 20). The control group (Ctr) was fed a basal diet containing an antibiotic (virginiamycin, 20 mg/kg). Meanwhile, broilers in experimental groups received Sb and Bs (1 × 10(8) cfu/kg of feed) in addition to the basal diet for 72 d. The results of the experimental groups revealed a significant improvement in live BW and relative weight of bursa of Fabricius and thymus. Also, intestinal villus height, width, and number of goblet cells increased in the Sb and Bs groups. Meanwhile, modulation in the intestinal ultrastructure and increased mRNA expression levels of occluding, cloudin2, and cloudin3 (P < 0.05) were observed in the Sb and Bs groups. Moreover, IgA-positive cells significantly increased in the jejunum of Sb- and Bs-supplemented groups (P < 0.05). Intestinal cytokines interleukin-6, tumor necrosis factor-α, interleukin-10, transforming growth factor-ß, and secretory IgA concentrations were (P < 0.05) improved in the probiotic groups; however, Sb induced inflammatory and antiinflammatory cytokines (P < 0.05) in comparison with the Ctr group. The present findings conclusively revealed that Sb and Bs increased IgA-positive cells in the lumen of the intestinal villus and revealed that Sb and Bs could modulate intestinal ultrastructure through increasing occluding, cloudin2, and cloudin3 mRNA expression levels in broiler intestine.


Asunto(s)
Bacillus subtilis/metabolismo , Pollos/fisiología , Intestinos/inmunología , Intestinos/ultraestructura , Probióticos/administración & dosificación , Saccharomyces/metabolismo , Animales , Claudinas/metabolismo , Citocinas/metabolismo , Suplementos Dietéticos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Inmunidad Mucosa , Mucosa Intestinal/inmunología , Mucosa Intestinal/ultraestructura , Microscopía Electrónica de Transmisión , Ocludina/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Especificidad de la Especie
10.
Fish Shellfish Immunol ; 34(6): 1485-95, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23528875

RESUMEN

The study assesses the effects of dietary mannan oligosaccharides (MOS) in European sea bass (Dicentrarchus labrax) posterior intestinal lipid class composition and its possible relation to the potential prostaglandins production and Gut Associated Lymphoid Tissue (GALT) stimulation. Fish were fed 4 g kg(-1) MOS (Bio-Mos(®) Aquagrade, Alltech, Inc., USA) for eight weeks. Fish fed MOS presented higher (P ≤ 0.05) weight gain, total length, and specific and relative growth rates than fish fed the control diet. Stimulated posterior gut of fish fed MOS showed higher (P ≤ 0.05) prostaglandins production than fish fed the control diet. Lipid class analyses of posterior gut revealed a reduction (P ≤ 0.05) in the neutral lipid fraction in fish fed MOS compared to fish fed the control diet, particularly due to a reduction (P ≤ 0.05) in triacylglycerols content. The polar lipid fraction increased (P ≤ 0.05) in fish fed MOS compared to fish fed the control diet, mainly due to an increase (P ≤ 0.05) in phosphatidylethanolamine and phosphatidylcoline contents. Light microscopy of posterior gut revealed increased number or goblet cells as well as higher level of infiltrated eosinophilic granulocytes for fish fed MOS. Transmission electron microscopy qualitative observations revealed a better preserved cytoarchitecture of the intestinal epithelial barrier in the posterior gut of fish fed MOS. Posterior gut of fish fed MOS presented more densely packed non-damaged enterocytes, better preserved tight junctions structure, healthier and more organized microvilli, and a higher presence of infiltrated lymphocytes and granulocytes compared fish fed the control diet. The present study indicates that dietary MOS enhances European sea bass posterior gut epithelial defense by increasing membrane polar lipids content in relation to a stimulation of the eicosanoid cascade and GALT, promoting posterior gut health status.


Asunto(s)
Lubina/metabolismo , Carbohidratos de la Dieta/administración & dosificación , Intestinos/efectos de los fármacos , Tejido Linfoide/metabolismo , Mananos/administración & dosificación , Prostaglandinas/metabolismo , Animales , Lubina/anatomía & histología , Cromatografía/veterinaria , Suplementos Dietéticos/análisis , Técnicas para Inmunoenzimas/veterinaria , Mucosa Intestinal/metabolismo , Intestinos/ultraestructura , Tejido Linfoide/citología , Microscopía Electrónica de Transmisión/veterinaria , Oligosacáridos/administración & dosificación
11.
PLoS One ; 7(1): e30119, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22253901

RESUMEN

Candida albicans is an opportunistic pathogen that proliferates in the intestinal tract of critically ill patients where it continues to be a major cause of infectious-related mortality. The precise cues that shift intestinal C. albicans from its ubiquitous indolent colonizing yeast form to an invasive and lethal filamentous form remain unknown. We have previously shown that severe phosphate depletion develops in the intestinal tract during extreme physiologic stress and plays a major role in shifting intestinal Pseudomonas aeruginosa to express a lethal phenotype via conserved phosphosensory-phosphoregulatory systems. Here we studied whether phosphate dependent virulence expression could be similarly demonstrated for C. albicans. C. albicans isolates from the stool of critically ill patients and laboratory prototype strains (SC5314, BWP17, SN152) were evaluated for morphotype transformation and lethality against C. elegans and mice during exposure to phosphate limitation. Isolates ICU1 and ICU12 were able to filament and kill C. elegans in a phosphate dependent manner. In a mouse model of intestinal phosphate depletion (30% hepatectomy), direct intestinal inoculation of C. albicans caused mortality that was prevented by oral phosphate supplementation. Prototype strains displayed limited responses to phosphate limitation; however, the pho4Δ mutant displayed extensive filamentation during low phosphate conditions compared to its isogenic parent strain SN152, suggesting that mutation in the transcriptional factor Pho4p may sensitize C. albicans to phosphate limitation. Extensive filamentation was also observed in strain ICU12 suggesting that this strain is also sensitized to phosphate limitation. Analysis of the sequence of PHO4 in strain ICU12, its transcriptional response to phosphate limitation, and phosphatase assays confirmed that ICU12 demonstrates a profound response to phosphate limitation. The emergence of strains of C. albicans with marked responsiveness to phosphate limitation may represent a fitness adaptation to the complex and nutrient scarce environment typical of the gut of a critically ill patient.


Asunto(s)
Candida albicans/citología , Candida albicans/aislamiento & purificación , Enfermedad Crítica , Tracto Gastrointestinal/microbiología , Tracto Gastrointestinal/patología , Fosfatos/farmacología , Fosfatasa Ácida/metabolismo , Animales , Biopelículas/efectos de los fármacos , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/microbiología , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Heces/microbiología , Proteínas Fúngicas/metabolismo , Tracto Gastrointestinal/efectos de los fármacos , Humanos , Intestinos/efectos de los fármacos , Intestinos/microbiología , Intestinos/ultraestructura , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Mutación/genética , Fenotipo , Análisis de Secuencia de ADN , Transcripción Genética/efectos de los fármacos
12.
Food Funct ; 2(9): 529-40, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21904755

RESUMEN

In the healthy gut, NF-κB is a critical factor of the intestinal immune system, whereas inflammatory bowel diseases are associated with chronic activation of NF-κB. Previous studies indicated that coffee induces nuclear translocation of NF-κB in macrophages, an effect attributed to roasting products. In the present work, coffee extract or roasting products induced nuclear translocation of NF-κB in macrophages, Caco-2 cells, and primary human intestinal microvascular endothelial cells (up to fivefold, p<0.001). Since the effect clearly depended on the cell type, ex vivo experiments were performed with intact human gut tissue from biopsies. The uniformity of the specimens and tissue viability during ex vivo incubation for up to 2 h were verified. Roasting products led to a concentration dependent significant increase of nuclear translocation of NF-κB in human gut tissue (up to 2.85 fold increase, p=0.0321), whereas coffee extract induced a trend towards higher nuclear NF-κB concentration. NF-κB activation in macrophages and Caco-2 cells by roasting products was significantly blocked by co-incubation with catalase (p=0.011 and p=0.024) indicating involvement of H(2)O(2)-signaling. Monitoring of extracellular H(2)O(2) indicated that roasting products in coffee constantly generate H(2)O(2) by spontaneous oxygen reduction, which is only partially detoxified by cellular antioxidative systems. Thus, it can be concluded that ex vivo stimulation of intact human gut tissue is a valuable model to study nutritional effects on complex tissue systems. Furthermore, the consumption of coffee and roasting products may be able to induce nuclear NF-κB translocation in the human gut.


Asunto(s)
Núcleo Celular/metabolismo , Café/química , Intestinos/efectos de los fármacos , Intestinos/ultraestructura , FN-kappa B/metabolismo , Células CACO-2 , Línea Celular , Coffea/química , Citocinas/metabolismo , Calor , Humanos , Peróxido de Hidrógeno/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/ultraestructura , FN-kappa B/efectos de los fármacos , Extractos Vegetales/farmacología , Polímeros/farmacología , Transporte de Proteínas/efectos de los fármacos , Semillas/química
13.
Cell Tissue Res ; 344(1): 135-46, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21258943

RESUMEN

The aim of the present study was to assess the effect of a commercial alginic acid source (Ergosan) on tilapia Oreochromis niloticus intestinal microbial balance, intestinal morphology, and growth parameters. Fish were fed a basal control diet or the basal diet plus a source of alginic acid (5 g kg(-1) Ergosan; Schering-Plough Aquaculture, UK) for 9 weeks. At the end of the trial, light and electron microscopy demonstrated that the morphology of the intestinal tract at the gross and ultra-structural level was not affected by dietary alginic acid inclusion. Both groups of fish displayed healthy, normal morphology with no signs of disease, cell or tissue damage. Intestinal epithelial leucocyte infiltration was not affected by dietary alginic acid. Molecular bacterial profiles derived from PCR-DGGE illustrated highly similar microbial communities (both within the lumen and associated with the intestinal mucosa) in the respective treatment groups. Microbial ecological parameters (e.g. species diversity and richness) also remained unaffected. Although not significant, trends towards elevated survival and body protein content were observed in the alginic acid-fed fish. These results are suggestive that alginic acid does not adversely impact the indigenous gastrointestinal microbial balance and subsequently does not impact upon the epithelial brush border integrity. Validation of non-detrimental impacts of immunostimulatory products on gastric microbiota and epithelial integrity should be pursued in future studies as maintaining microbial balance and epithelial integrity is essential for proper gut functionality.


Asunto(s)
Adyuvantes Inmunológicos/metabolismo , Alginatos/metabolismo , Suplementos Dietéticos , Intestinos/microbiología , Tilapia/crecimiento & desarrollo , Animales , Ácido Glucurónico/metabolismo , Ácidos Hexurónicos/metabolismo , Intestinos/ultraestructura , Phaeophyceae/metabolismo , Tilapia/metabolismo
14.
J Agric Food Chem ; 57(19): 9316-23, 2009 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-19731962

RESUMEN

Extracts of kidney beans ( Phaseolus vulgaris ) are known to reduce food intake and glycemia in rodents and humans. This study evaluated the effect of a novel extract of P. vulgaris on food (regular food pellets, starch-enriched diet, and chocolate-flavored beverage) intake, body weight, and glycemia in rats. The effect of the combination of the colecistokinin (CCK) receptor antagonist, lorglumide, and P. vulgaris dry extract on food intake was also investigated. Administration of doses of P. vulgaris dry extract devoid of any behavioral toxicity dose-dependently decreased food intake (irrespective of the diet), body weight gain, and glycemia. Pretreatment with lorglumide blocked the reducing effect of P. vulgaris dry extract on food intake. The capacity of this P. vulgaris dry extract to reduce food intake, body weight, and glycemia in rats may be due to (a) inhibition of alpha-amylase, (b) stimulation of CCK release from the intestinal brush border cells, and/or (c) interference with the central mechanism(s) regulating appetite, food intake, and food palatability.


Asunto(s)
Glucemia/análisis , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Phaseolus/química , Extractos Vegetales/farmacología , Animales , Colecistoquinina/metabolismo , Interacciones Farmacológicas , Ingestión de Energía/efectos de los fármacos , Intestinos/ultraestructura , Masculino , Microvellosidades/metabolismo , Proglumida/análogos & derivados , Proglumida/farmacología , Ratas , Ratas Wistar , Receptores de Colecistoquinina/antagonistas & inhibidores , alfa-Amilasas/antagonistas & inhibidores
15.
Br Poult Sci ; 50(1): 123-30, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19234936

RESUMEN

1. To investigate the growth performance and histological intestinal alterations of Aigamo ducks fed on dietary combinations of zeolite, plant extract and vermiculite (ZEM, 14-d-old Aigamo ducks were divided into 4 groups, with 3 replicates of 3 male and 3 female ducks. They were fed ad libitum on a basal commercial duck mash diet with 0, 0.1, 0.5 and 1.0 g/kg dietary ZEM for 63 d. 2. Body weight gain tended to be higher for the 0.1 and 0.5 g/kg ZEM groups than for the control group at 9 weeks. 3. In light microscopic observation, most values of the intestinal villus height, villus area, cell area and cell mitosis numbers were higher in the ZEM group than those of the control in all intestinal segments, and the duodenal villus height, cell area and cell mitosis of the 0.5 g/kg ZEM group, as well as jejunal cell mitosis in the 0.1 g/kg ZEM group, increased (P < 0.05). In the scanning electron microscope results, all ZEM groups showed protuberant epithelial cells and cell clusters on the villus apical surface of the duodenum and ileum. In the jejunum, villus gyri were frequently observed in the 0.1 g/kg ZEM group. These histological intestinal alterations suggest that intestinal villi and epithelial cellular functions might have been activated. 4. From the present results, dietary ZEM showed hypertrophied functions of intestinal villi and epithelial cells at the duodenum and ileum, and the 0.1 and 0.5 g/kg levels improved body weight gain. These suggest that the ZEM can be supplemented until a level of 1.0 g/kg.


Asunto(s)
Silicatos de Aluminio/administración & dosificación , Patos/crecimiento & desarrollo , Mucosa Intestinal/metabolismo , Extractos Vegetales/administración & dosificación , Zeolitas/administración & dosificación , Animales , Peso Corporal , Patos/metabolismo , Ingestión de Alimentos , Femenino , Histocitoquímica/veterinaria , Intestinos/citología , Intestinos/ultraestructura , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Distribución Aleatoria
16.
Artículo en Chino | MEDLINE | ID: mdl-21158035

RESUMEN

AIM: To explore effects of Safflor (Chinese Tradional Medicine) on the intestine ultrastructure characteristics during intestine ischemia/ reperfusion injury (I/RI) in rabbits. METHODS: Thirty rabbits were randomly divided into three groups: control group (group S), ischemia/reperfusion group (group I/R) and Safflor injection group (group SI). Morphological changes of intestine ischemia/reperfusion in rabbits and the protective effects of Safflor were observed under electric telescope. RESULTS: The intestine ultrastructure was badly injured in group I/R. Mitochondria and intestinal mucosal cells were swellen and endoplasmic reticulum expanded, however, in the SI group the ultrastructural injury of the ischemia greatly ameliorated. CONCLUSION: The ultrastructure injury occurrted after intestine I/RI and Safflor has protective effects on the intestine ultrastructure.


Asunto(s)
Carthamus tinctorius/química , Medicamentos Herbarios Chinos/farmacología , Intestinos/irrigación sanguínea , Intestinos/ultraestructura , Daño por Reperfusión/prevención & control , Animales , Femenino , Masculino , Conejos
17.
J Int Med Res ; 35(5): 644-56, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17900404

RESUMEN

Traumatic brain injury (TBI) can induce a persistent inflammatory response, histopathological changes and apoptosis in the intestine. Glutamine has been shown to reduce bacterial translocation and maintain intestine mucosal integrity, but its effects on the inflammatory response, structural alterations and apoptosis in intestinal mucosa following TBI have not been previously investigated. Using the weight-drop method, a right parietal cortical contusion was induced in rats and, for the next 5 days, they were fed either chow alone or chow mixed with glutamine. Intestinal tissue samples were then removed for analysis. Following TBI, glutamine supplementation was found to: decrease intestinal concentrations of interleukin (IL) -1beta, tumour necrosis factor-alpha (TNF-alpha) and IL-6; downregulate intercellular adhesion molecule-1 (ICAM-1) expression; attenuate TBI-induced damage to the intestine structure; and reduce apoptosis. These results suggest that post-TBI glutamine administration could suppress intestinal inflammation, protect intestinal mucosal structure and reduce mucosal apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Lesiones Encefálicas/patología , Glutamina/farmacología , Intestinos/efectos de los fármacos , Animales , Etiquetado Corte-Fin in Situ , Mucosa Intestinal/patología , Mucosa Intestinal/ultraestructura , Intestinos/patología , Intestinos/ultraestructura , Masculino , Microscopía Electrónica de Transmisión , Ratas , Ratas Wistar
18.
Br Poult Sci ; 47(5): 544-53, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17050097

RESUMEN

1. Sugar cane extract (SCE) is the residue after removing glucose, fructose and sucrose from sugar cane juice. To investigate the effects of dietary SCE on growth performance and alterations to intestinal histology, 36 male Sanuki Cochin chickens were divided into three groups: a control group was fed a commercial diet (180 g/kg CP, 13.59 MJ/kg ME) and the treatment groups were fed the commercial diet supplemented with 0.5 or 10 g/kg SCE ad libitum for 35 d. 2. Feed intake and weight gain tended to be higher in the 0.5 and 10 g/kg SCE groups than in the control group. No specific gross morphological alterations were observed in the visceral organs of chickens in any of the groups. However, intestinal villus height, villus area, epithelial cell area and cell mitosis in each intestinal segment had higher values in the SCE groups than in the control group. In the 0.5 and 10 g/kg SCE groups, but not in the control group, the cells on the villus apical surface protuberated and had larger cell clusters and some areas with cells with no microvilli. 3. The observed alterations to intestinal histology in chickens fed dietary SCE diets demonstrate that the function of villi and cells on the villus tip might be activated in all the intestinal segments and that cell turnover is also accelerated. These activated intestinal functions appear to promote growth and immuno-stimulation in chickens fed SCE diets, especially in the 0.5 g/kg group.


Asunto(s)
Pollos/metabolismo , Dieta/veterinaria , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Intestinos/citología , Intestinos/efectos de los fármacos , Saccharum , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Células Epiteliales/ultraestructura , Intestinos/ultraestructura , Masculino , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología
19.
J Agric Food Chem ; 53(14): 5541-8, 2005 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-15998111

RESUMEN

The effect of daily contact with ethanol on Caco-2 cell differentiation was investigated. Pure ethanol (1%) and a polyphenolic free wine matrix (polyphenol-free wine containing 1% ethanol) associated or not with a procyanidin-rich grape seed extract (GSE) were added to Caco-2 cells from confluency for 2 h a day after successive incubation in salivary, gastric, and pancreatic media. Treatment with 1% ethanol did not appear to be cytotoxic to cells, but it also stimulated Caco-2 cell differentiation, particularly in the first days following confluency, and this effect was more marked when associated with polyphenolic free wine matrix constituents. This activation resulted in an increase in microvillar density, organization, and elongation (+70%) and was associated with strong stimulation of sucrase-isomaltase (+780%) and a concomitant regular increase in cell protein content (+50-88%). While the presence of GSE in alcoholic solutions did not modify the morphological pattern observed in cells subjected to ethanol and polyphenolic free wine matrix alone, it had a clear reducing effect on their microvillus elongation (-30%). However, these stimulating effects of ethanol on morphological differentiation were attenuated from day 10 postconfluency, which could suggest cell cytoprotection against ethanol. These are the first results in support of the notion that moderate concentration of ethanol may stimulate the differentiation of Caco-2 cells, particularly when integrated with a polyphenolic free wine matrix.


Asunto(s)
Biflavonoides/análisis , Catequina/análisis , Diferenciación Celular/efectos de los fármacos , Etanol/farmacología , Flavonoides/análisis , Mucosa Intestinal/citología , Fenoles/análisis , Proantocianidinas/análisis , Vitis/química , Vino/análisis , Células CACO-2 , Muerte Celular/efectos de los fármacos , Humanos , Hidrolasas/metabolismo , Mucosa Intestinal/efectos de los fármacos , Intestinos/ultraestructura , Microvellosidades/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polifenoles , Semillas/química
20.
Arch Insect Biochem Physiol ; 57(1): 1-14, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15352151

RESUMEN

Alfalfa leafcutting bees, Megachile rotundata (F.), overwinter as prepupae. The internal lipids were extracted from prepupae that had been wintered at 4 degrees C for 7 months. Megachile rotundata prepupae possessed copious quantities of internal lipids (20% of the fresh weight) that were extracted with CHCl3/methanol (2:1). Transmission electron microscopy revealed that lipids were stored within very large intracellular vacuoles. Separation by silica chromatography revealed that 88% of the internal lipids were triacylglycerols. Ester derivatives of fatty acids from triacylglycerol components were analyzed by gas chromatography-mass spectrometry and 15 fatty acid constituents were identified. The majority (76%) of the triacylglycerol fatty acids were unsaturated fatty acids. The major triacylglycerol fatty acid constituent (30%) was the C16 monounsaturated fatty acid, palmitoleic acid (16:1, hexadec-9-enoic acid), with substantial amounts of linolenic acid (18:3, octadec-9,12,15-trienoic acid, 15%), palmitic acid (16:0, hexadecanoic acid, 14%) and oleic acid (18:1, octadec-9-enoic acid, 13%). Palmitoleic acid as the major fatty acid of an insect is an unusual occurrence as well as the presence of the 16-carbon polyunsaturated fatty acids, 16:2 and 16:3. The major intact triacylglycerol components were separated and identified by high performance liquid chromatography-mass spectrometry. A complex mixture of approximately 40 triacylglycerol components were identified and major components included palmitoyl palmitoleoyl oleoyl glycerol, palmitoyl palmitoleoyl palmitoleoyl glycerol, myristoyl palmitoleoyl palmitoleoyl glycerol, myristoleoyl palmitoyl palmitoleoyl glycerol, and palmitoyl palmitoleoyl linolenoyl glycerol. The function of these internal lipids and their relevance to winter survival and post-wintering development of M. rotundata is discussed.


Asunto(s)
Abejas/química , Hibernación/fisiología , Intestinos/ultraestructura , Triglicéridos/análisis , Vacuolas/ultraestructura , Cigoto/química , Animales , Abejas/embriología , Abejas/fisiología , Abejas/ultraestructura , Cromatografía , Cromatografía Líquida de Alta Presión , Ácidos Grasos/clasificación , Ácidos Grasos/aislamiento & purificación , Intestinos/química , Estadios del Ciclo de Vida/fisiología , Espectrometría de Masas , Medicago sativa , Polen , Vacuolas/química , Cigoto/fisiología , Cigoto/ultraestructura
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