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1.
J Anim Physiol Anim Nutr (Berl) ; 102(1): 350-355, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28251704

RESUMO

Ochratoxin A (OTA) is a potent nephrotoxic fungi metabolite that affects animal and human health. At the cellular level, OTA is able to alter functions and viability by several mechanisms of action. Several strategies to counteract its toxicity have been studied. We investigated the role of α-tocopherol in counteracting OTA oxidative damage in Madin-Darby canine kidney (MDCK) cells by pre-incubating the cells for 3 hr with the antioxidant (1 nm, 10 µm) and then adding OTA (0-1.2 µg/ml) for the following 24 hr. Cell viability, lactate dehydrogenase (LDH) release, TUNEL staining and occludin and Zo1 localization by immunofluorescence were determined. Here, 1 nm α-tocopherol was shown to significantly reduce (p < .05) the cytotoxicity, LDH release and apoptotic rate induced by OTA. The presence of the antioxidant at the same concentration maintained the localization of occludin and Zo1 in the rim of the MDCK cells after the 24-hr OTA exposure. These results indicate that a low concentration of α-tocopherol could block OTA toxicity, supporting its defensive role in the cellular membrane.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Ocratoxinas/toxicidade , Junções Íntimas/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Dano ao DNA , Cães , Ocludina , Transporte Proteico , Proteína da Zônula de Oclusão-1/metabolismo
2.
Animal ; 9(11): 1760-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26189883

RESUMO

The aim of this study was to compare low doses of microencapsulated v. pharmacological ZnO in the diet of piglets on growth performance, ileum health status and architecture. One hundred and forty-four piglets weaned at 28 days and divided in 36 pens (two males and two females per pen), received a basal diet (control, Zn at 50 mg/kg) or the basal diet with ZnO at 3000 mg/kg (pZnO), or with lipid microencapsulated ZnO at 150 or 400 mg/kg (mZnO-300 and mZnO-800, respectively). After 14 and 42 days, three pigs per sex per treatment were euthanized to collect the ileum mucosa for immunohistochemistry, histomorphology, inflammatory cytokines and tight junction components gene expression. Data were analyzed with one-way ANOVA. At 0 to 14 days, the pZnO and mZnO-800 groups had greater average daily gain compared with control (P<0.05). Gain to feed ratio (G:F) in the same time interval was higher in pZnO group compared with control thus resulting in higher BW (P<0.05). At day 14, ileum villi height in mZnO-800 pigs was 343 µm v. 309 and 317 µm in control and pZnO, respectively (P<0.01) and villi:crypts ratio (V:C), as well as cells positive to proliferating cell nuclear antigen (PCNA), were greater in all treated groups compared with control (P<0.01). In mZnO-800 group, interferon-γ mRNA was the lowest (P=0.02), and both pharmacological ZnO and mZnO reduced tumor necrosis factor-α protein level (P<0.0001). Compared with pZnO group, mZnO-800 increased occludin and zonula occludens-1 protein level (1.6-fold and 1.3-fold, respectively; P<0.001). At day 42, both groups receiving microencapsulated ZnO had 1.7 kg greater BW than control and did not differ from pZnO group (P=0.01); ileum villi height and V:C ratio were the greatest for pZnO compared with the other groups, whereas PCNA-positive cells were the most numerous in mZnO-800 group (P<0.001). In conclusion, pigs receiving low doses of microencapsulated ZnO had G:F comparable with those receiving pharmacological level of ZnO in the overall post-weaning phase. Moreover, in the first 2 weeks post-weaning, microencapsulated ZnO effect on inflammatory status and ileum structure and integrity was comparable with pharmacological ZnO.


Assuntos
Citocinas/metabolismo , Suplementos Nutricionais , Doenças dos Suínos/tratamento farmacológico , Óxido de Zinco/administração & dosagem , Animais , Dieta/veterinária , Composição de Medicamentos/veterinária , Feminino , Regulação da Expressão Gênica , Íleo/efeitos dos fármacos , Íleo/imunologia , Inflamação/veterinária , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Masculino , Suínos , Junções Íntimas/metabolismo
3.
Animal ; 9(3): 417-26, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25275341

RESUMO

The aim of this study was to test the hypothesis of an improved gut environment of post-weaning piglets when administered a blend of essential oils (EO; thymol and cinnamaldehyde) and an enzyme combination (xylanase and ß-glucanase (XB)) either alone or in combination. To assess the effect of dietary treatments, faecal nutrient digestibility and microbial counts, as well as ileum histology and gene expression of inflammatory mediators were evaluated. One hundred and ninety-two weaned piglets were allocated into four experimental treatments, and fed the basal diet (CTRL) either without or with EO, XB or their combination (EO+XB) for a 42-day period. The experiment concerning digestibility was designed with two periods (period I: days 15 to 21; period II: days 29 to 35) and the faeces were collected on days 20, 21, 34 and 35. On day 42, six piglets from each treatment were slaughtered. It was found that EO, XB and EO+XB supplementation did not affect (P>0.05) the growth performance of the piglets from days 0 to 42. Moreover, no dietary effect on faecal score was observed. Faecal digestibility of dry matter, organic matter, ash, dietary fibre, lipid, CP and NDF were increased from period I to period II (P<0.01 to P=0.06), while no effect (P>0.05) of EO, XB or their combination on the faecal digestibility was observed at both periods. Compared with the CTRL diet, dietary XB reduced the faecal Lactobacillus and Escherichia coli counts but increased the Lactobacillus to Coliforms ratio on day 42 (P=0.02, 0.03 and 0.03, respectively), and all the additives supplementations decreased the counts of faecal Coliforms on day 42 (P<0.01). XB supplementation increased the villus to crypt ratio (P=0.04) and reduced the mucosal macrophages number (P<0.01) in the ileum compared with the CTRL group, and dietary EO or EO+XB decreased the number of lymphatic follicles (P=0.01 and P<0.01, respectively) and mucosal macrophages (P=0.02 and P<0.01, respectively). In addition, the interleukin (IL)-1α was downregulated in piglets treated with EO+XB compared with the EO group (P=0.02). In conclusion, the administration of EO, XB or their combination was effective in improving ileum histology, and EO+XB supplementation might benefit the modulation of the expression of ileum inflammatory cytokines in piglets.


Assuntos
Suplementos Nutricionais , Digestão/efeitos dos fármacos , Endo-1,4-beta-Xilanases/farmacologia , Glicosídeo Hidrolases/farmacologia , Óleos Voláteis/farmacologia , Suínos/fisiologia , Ração Animal/análise , Animais , Dieta/veterinária , Quimioterapia Combinada , Endo-1,4-beta-Xilanases/administração & dosagem , Fezes/química , Fezes/microbiologia , Glicosídeo Hidrolases/administração & dosagem , Íleo/metabolismo , Intestino Delgado , Óleos Voláteis/administração & dosagem
4.
Animal ; 8(5): 721-30, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24739350

RESUMO

The present study evaluated the effects of a novel plant extract (PE) product (GrazixTM) on the performance and gut health of weaned piglets challenged with Escherichia coli. The PE was a standardised mixture of green tea leaves (Camellia sinensis) and pomegranate fruit (Punica granatum) obtained by using the LiveXtract™ process. A total of 144 piglets were weaned at 24 days and allocated to 8 for a 35-day experiment with a 2×2×2 factorial design comparing different treatments (water without product (CT) or 8 µl/kg per day PE in drinking water (PE)), feeding regimens (ad libitum (AD) or restricted (RE)) and oral E. coli challenges on day 9 (sham (-) or infected (+)). There were six pens per group with three piglets per pen. On day 35, 24 of the RE feeding piglets were slaughtered. It was found that PE supplementation increased the average daily gain (ADG) from day 28 to day 35 (P=0.03) and increased the gain to feed ratio (G : F) from day 7 to day 14 (P=0.02). RE feeding led to lower feed intake in piglets during the 1st week (P<0.01), 2nd week (P=0.06), 3rd week (P=0.05), and throughout the course of the overall study period (P=0.05). E. coli challenge decreased the ADG and G : F ratio from day 7 to day 14 (P=0.08 and <0.01, respectively) and increased the faecal score (higher values indicate more severe diarrhoea) on days 14, 21, 28 and 35 (P<0.01). PE supplementation decreased the faecal score in the challenged piglets during the 1st week post-challenge (P<0.01). E. coli challenge increased the faecal E. coli level on day 14 (P=0.03) and increased the Enterobacteriaceae level on day 35 (P<0.01). Reduced faecal E. coli was observed on days 14 and 35 (P=0.05 and 0.02, respectively), and reduced Enterobacteriaceae (P<0.01) was found on day 35 in the PE animals. RE feeding increased the faecal Lactobacillus, Enterobacteriaceae and E. coli levels on day 35 (P=0.02, <0.01 and <0.01, respectively). These results suggest that PE supplementation may improve the gut health status of post-weaning piglets and counteract some of the negative effects that occur when piglets are challenged with E. coli.


Assuntos
Suplementos Nutricionais , Infecções por Enterobacteriaceae/veterinária , Infecções por Escherichia coli/veterinária , Extratos Vegetais/administração & dosagem , Doenças dos Suínos/prevenção & controle , Suínos/fisiologia , Animais , Camellia sinensis/química , Diarreia/veterinária , Água Potável , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/prevenção & controle , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/prevenção & controle , Fezes/microbiologia , Frutas/química , Lactobacillus/isolamento & purificação , Lythraceae/química , Folhas de Planta/química , Distribuição Aleatória , Desmame , Aumento de Peso/efeitos dos fármacos
5.
J Appl Microbiol ; 114(2): 308-17, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23110383

RESUMO

AIM: In vitro and in vivo challenge studies were undertaken to develop an in-feed additive of microencapsulated propionic, sorbic acids and pure botanicals to control Campylobacter jejuni in broilers at slaughter age. METHODS AND RESULTS: Organic acids (OA) and pure botanicals were tested in vitro against Camp. jejuni, whereas in vivo, chickens were fed either a control diet, or increasing doses of the additive for 42 days (experiment 1); in the second experiment, chickens received the additive at 0.1 or 0.3% from day 0 to 21 or from day 22 to 42. The additive consistently reduced Camp. jejuni caecal counts at any given dose (exp. 1) or inclusion plan (exp. 2). Moreover, it was able to reduce the number of goblet cells and modify mucin glycoconjugates biosynthesis pattern. CONCLUSIONS: We developed an additive that was effective in reducing Camp. jejuni in slaughter-age chickens even at low doses (0.1%). That efficacy was the result of the synergistic action between OA and botanicals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a strategy to reduce Camp. jejuni in broilers and, as a consequence, to improve the safety of the food chain. Moreover, data suggest that a treatment limited to the last weeks before slaughter would allow to save on inclusion of the additive throughout the whole production cycle.


Assuntos
Ração Animal , Infecções por Campylobacter/veterinária , Campylobacter jejuni/efeitos dos fármacos , Galinhas/microbiologia , Aditivos Alimentares/farmacologia , Doenças das Aves Domésticas/microbiologia , Animais , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/patologia , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/isolamento & purificação , Ceco/citologia , Ceco/microbiologia , Eugenol/farmacologia , Mucosa Intestinal/patologia , Doenças das Aves Domésticas/patologia , Propionatos/farmacologia , Ácido Sórbico/farmacologia , Timol/farmacologia
6.
Animal ; 5(4): 547-57, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22439951

RESUMO

Although the effects of pig genotype on total-tract apparent digestibility (TTAD) have been widely reported in the literature, there is controversial information on the digestive capacity of indigenous breeds compared with lean-type pigs. The strategy of this study was to test the effects of pig genotype and crude protein (CP) supply on performance, digestive utilization of nutrients, relative organ weight and morphometric analysis of the small intestine. Thirty-eight Iberian (IB) and Landrace × Large White (LD) pigs were used. Three pigs per genotype were slaughtered at approximately 15 kg BW. The remaining pigs were fed one of two diets differing in CP content (13% or 17% as fed) using a pair-fed procedure. Feeding level was restricted at 0.8 × ad libitum of IB pigs. Nutrient digestibility and nitrogen (N) balance trials were performed at 30 and 80 kg BW. Four pigs per dietary treatment and genotype were slaughtered at approximately 50 and 115 kg BW. The gastrointestinal tract and the rest of the visceral organs were weighed and samples of the small intestine were taken to carry out histological and histometrical studies. Daily gain and gain-to-feed ratio were higher in LD than in IB pigs during the fattening and growing-fattening periods (P < 0.01). N TTAD was significantly higher for LD pigs at 30 kg BW (P < 0.05), whereas at 80 kg BW we observed greater values for digestibility of organic matter and energy in IB pigs (averaging 1.5%, P < 0.01). Both N retention (NR) and efficiency of NR were increased in LD pigs at 30 and 80 kg BW (30% as mean value). The proportional weight of the small intestine was greater in LD than in IB pigs at 50 and 115 kg BW. Histometry showed that IB presented a lower muscle layer thickness than LD pigs in ileum, irrespective of the BW (P < 0.05). In contrast, LD pigs showed approximately 10% higher ileal villi length and villi-to-crypt ratio than IB pigs at 115 kg BW. CP supply affected to a larger extent the small intestinal micro-anatomical structure of LD pigs at 50 kg BW. In conclusion, our results suggests that although the higher growth rate, NR and efficiency of NR observed in LD pigs might be associated with presumably more efficient structural aspects of the small intestine, the main differences between the two genotypes should be attributed to a larger extent to protein and energy utilization in tissues with consequences for the overall efficiency of energy use.

7.
Neurogastroenterol Motil ; 22(9): e271-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20524986

RESUMO

BACKGROUND: The enteric nervous system (ENS) contains chemically coded populations of neurons that serve specific functions for the control of the gastrointestinal tract. The ability of neurons to modify their chemical code in response to luminal changes has recently been discovered. It is possible that enteric neuronal plasticity may sustain the adaptability of the gut to changes in intestinal activity or injury, and that gut neurons may respond to an altered intestinal environment by changing their neuropeptide expression. METHODS: We used immunohistochemical methods to investigate the presence and localization of several neuronal populations and enteric glia in both the small (ileum) and large (cecum) intestine of piglets. We assessed their abundance in submucosal and myenteric plexus from animals treated with the probiotic Pediococcus acidilactici compared with untreated controls. KEY RESULTS: The treated piglets had a larger number of galanin- and calcitonin gene-related peptide (CGRP)-immunoreactive neurons than controls, but this was limited to the submucosal plexus ganglia of the ileum. Moreover, immunohistochemistry revealed that glial fibrillary acidic protein-positive enteric glial cells were significantly higher in the inner and outer submucosal plexuses of treated animals. CONCLUSIONS & INFERENCES: The neuronal and glial changes described here illustrate plasticity of the ENS in response to an altered luminal environment in the gastrointestinal tract.


Assuntos
Ceco/metabolismo , Dieta , Sistema Nervoso Entérico/metabolismo , Íleo/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Probióticos/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Ceco/citologia , Contagem de Células , Sistema Nervoso Entérico/citologia , Feminino , Galanina/metabolismo , Íleo/citologia , Imuno-Histoquímica , Neuropeptídeo Y/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Pediococcus/metabolismo , Substância P/metabolismo , Suínos , Peptídeo Intestinal Vasoativo/metabolismo
8.
Knee Surg Sports Traumatol Arthrosc ; 17(6): 645-51, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19296087

RESUMO

Menisci represent fundamental structures for the maintenance of knee homeostasis, playing a key role in knee biomechanics. However, their intrinsic regenerative potential is poor. As a consequence, when a lesion occurs and the meniscus is partially removed by surgery, knee mechanics is subject to dramatic changes. These have been demonstrated to lead often to the development of early osteoarthritis. Therefore, menisci should be repaired whenever possible. In the last decades, tissue engineering approaches have been advocated to improve the reparative processes of joint tissues. In this study, the bonding capacity of an articular chondrocytes-fibrin glue hydrogel was tested as a biologic glue to improve the bonding between two swine meniscal slices in a nude mouse model. The composites were wrapped with acellular fibrin glue and implanted in subcutaneous pouches of nude mice for 4 weeks. Upon retrieval, a firm gross bonding was observed in the experimental samples while none of the control samples, prepared with acellular fibrin glue at the interface, presented any sign of bonding. This was consistent with the histological and scanning electron microscope findings. In particular, a fibrocartilaginous tissue was found at the interface between the meniscal slices, partially penetrating the native meniscus tissue. In order to overcome the lack of regenerative properties of the meniscus, the rationale of using cellular fibrin glue is that fibrin provides immediate stability while carrying cells in the site of lesion. Moreover, fibrin gel is recognized as an optimal scaffold for cell embedding and for promoting fibrocartilaginous differentiation of the cells which synthesize matrix having healing property. These results demonstrated the potential of this model for improving the meniscal bonding. However, further orthotopic studies in a large animal model are needed to evaluate its potential for clinical application.


Assuntos
Condrócitos/transplante , Adesivo Tecidual de Fibrina/uso terapêutico , Meniscos Tibiais/ultraestrutura , Adesivos Teciduais/uso terapêutico , Engenharia Tecidual/métodos , Cicatrização , Animais , Meniscos Tibiais/patologia , Camundongos , Camundongos Nus , Sus scrofa , Lesões do Menisco Tibial
9.
Histol Histopathol ; 23(6): 651-64, 2008 06.
Artigo em Inglês | MEDLINE | ID: mdl-18366003

RESUMO

Probiotic research has been approached, above all in recent years, by widely differing points of view, both for human and animal uses. Lactic acid bacteria release bacteriocins, and some of them may function as probiotic. The aim of the present study was to investigate the effects of dietary supplementation with the probiotic Pediococcus acidilactici on the piglet intestine, on circulating lymphocytes, and on aspects of piglet performance during the first 42 days after weaning. Sixteen female piglets were at weaning assigned to two dietary groups: Control (Ctr, 8 animals) and Pediococcus acidilactici supplemented (Pa, 8 animals). Piglets' growth was monitored from weaning to the end of the trial. On day 42 post-weaning, the piglets were slaughtered and small specimens from both ileum and cecum were examined with haematoxylin/eosin staining to ascertain structural details. Histometry was performed by villi and crypts measurements, as well as GALT measurements. Histochemical analyses were performed to investigate the intestinal mucins. Immunohistochemical analyses were used to visualize proliferating as well as apoptotic mucosal cells, and to identify mucosal macrophages and IgA producing cells. Intra-epithelial CD8+ T lymphocytes were identified and counted. Subsets of circulating T lymphocytes were analyzed by flow cytometry. Pediococcus acidilactici supplementation positively influenced weight and post-weaning average daily gain of treated piglets. Histometry showed an increase in villi height and crypts depth in Pa animals in comparison with controls. Treated piglets showed a larger number of proliferating enterocytes than controls. Intra-epithelial CD8+ T lymphocytes were scarcer in treated than in control piglets, likely in relation with catarrhal enteritis shown in the latter. We conclude that the studied supplementation was possibly able to protect the piglet small intestinal mucosa, improving local resistance to infections in the stressful weaning period.


Assuntos
Ceco/patologia , Íleo/patologia , Pediococcus/fisiologia , Probióticos/administração & dosagem , Administração Oral , Fenômenos Fisiológicos da Nutrição Animal , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Ceco/imunologia , Ceco/microbiologia , Proliferação de Células/efeitos dos fármacos , Enterócitos/patologia , Feminino , Citometria de Fluxo , Íleo/imunologia , Íleo/microbiologia , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Subpopulações de Linfócitos/imunologia , Mucinas/metabolismo , Suínos
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