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1.
Br J Nutr ; 123(2): 172-181, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31495347

RESUMO

Resistant starch (RS) was recently approved to exert a powerful influence on gut health, but the effect of RS on the caecal barrier function in meat ducks has not been well defined. Thus, the effect of raw potato starch (RPS), a widely adopted RS material, on microbial composition and barrier function of caecum for meat ducks was determined. A total of 360 Cherry Valley male ducks of 1-d-old were randomly divided and fed diets with 0 (control), 12, or 24 % RPS for 35 d. Diets supplemented with RPS significantly elevated villus height and villus height:crypt depth ratio in the caecum. The 16S rRNA sequence analysis indicated that the diet with 12 % RPS had a higher relative abundance of Firmicutes and the butyrate-producing bacteria Faecalibacterium, Subdoligranulum, and Erysipelatoclostridium were enriched in all diets. Lactobacillus and Bifidobacterium were significantly increased in the 24 % RPS diet v. the control diet. When compared with the control diet, the diet with 12 % RPS was also found to notably increase acetate, propionate and butyrate contents and up-regulated barrier-related genes including claudin-1, zonula occludens-1, mucin-2 and proglucagon in the caecum. Furthermore, the addition of 12 % RPS significantly reduced plasma TNF-α, IL-1ß and endotoxin concentrations. These data revealed that diets supplemented with 12 % RPS partially improved caecal barrier function in meat ducks by enhancing intestinal morphology and barrier markers expression, modulating the microbiota composition and attenuating inflammatory markers.


Assuntos
Ração Animal/análise , Ceco/microbiologia , Patos/metabolismo , Patos/microbiologia , Amido/administração & dosagem , Animais , Ceco/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Carne , Microbiota/efeitos dos fármacos , RNA Ribossômico 16S/metabolismo , Solanum tuberosum
2.
Mol Cell Endocrinol ; 493: 110472, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31167113

RESUMO

Serotonin (5-HT) acts as a morphogen influencing embryonic brain development, and as a neurotransmitter regulating multiple biological functions with lifelong effects on animal physical, physiological and mental health, especially during the rapid growth phase prior to birth when embryos face many challenges to reach structural and functional completion. In this study, the development of the serotoninergic (5-HTergic) system and its modulatory effect on the dopaminergic (DAergic) system and related neural circuits were investigated during the mid-late embryogenesis, embryonic day (E)12-E20, in the chicken's brain. During 5-HTergic neuronal maturation, a growth-related anatomical and functional remodeling was highlighted: the 5-HT neurons continuously grew during E12-E20 except for a remarkable regression during E14-E16. Correspondingly, there was a time-dependent change in the 5-HT synthetic capacity. Specifically, 5-HT concentrations in the raphe nuclei increased from E12 to E14, reaching a first plateau during E14-E16, then continuously increased up to E19, and reaching a second plateau between E19-E20. The second plateau of the 5-HT concentration was in correspondence with the establishment of the 5-HTergic autoregulatory loop during E19-E20 and the development of the DAergic system. The DA concentrations remained unchanged from E12 to E16, then started to increase at E16, reaching a maximum at E19, and diminished before hatching. The unique developing time sequence between the 5-HTergic and DAergic systems suggests that the 5-HTergic system may play a critical role in forming the 5-HT - DA neural circuit during chicken embryogenesis. These results provide new insights for understanding the functional organization of the 5-HTergic system during embryonic development and raise the possibility that prenatally modulating the 5-HTergic system may lead to long-lasting brain structural and functional alterations.


Assuntos
Encéfalo/embriologia , Dopamina/metabolismo , Serotonina/metabolismo , Animais , Encéfalo/metabolismo , Galinhas , Cromatografia Líquida de Alta Pressão , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Receptor 5-HT1A de Serotonina/genética , Receptor 5-HT1A de Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo
3.
Poult Sci ; 96(9): 3096-3103, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28633471

RESUMO

Gut mucosa holds a single layer of epithelial cells and the largest mass of lymphoid tissue in the body. Although the epithelial cell culture model is widely used to assess intestinal barrier function, it has limitations for studying cellular interactions, in particular those of the immune system. In this study, a chicken ileal explant culture model was developed for investigating short-term gut inflammatory and secretory responses in an ex vivo environment. Initially, ileal explants from broilers at 21 d of age were cultured ex vivo up to 6 h. Explants cultured for a maximum of 2 h remained over 90% viable, based on lactate dehydrogenase (LDH) release assay. Morphologically, explants cultured for 2 h displayed normal morphology compared to those cultured longer, further confirming that short-term culture for up to 2 h duration is an acceptable model for studying ex vivo regulation of inflammation. Subsequently, lipopolysaccharide (LPS) dose-related responses were determined for explants cultured for 2 h. Results from LDH activity assay showed that the viability of explants was decreased (P ≤ 0.05) at an LPS dose higher than 50 µg/mL. A significant (P ≤ 0.05) nitric oxide release was observed at LPS concentrations of 10 and 20 µg/mL. In addition, the highest inflammatory and secretory responses were detected at 20 µg/mL LPS based on gene expression of TLR-4, IL-1ß, IL-8, MUC2, IgA, and pIgR (P ≤ 0.05). However, the gene expression of claudin-1 and claudin-4 were not increased at the determined LPS concentrations (P > 0.05). These results demonstrated the potential usefulness of this intestinal explant culture model for short-term study of biological factors in gut inflammatory and secretory responses, but not a sufficient duration for evaluation of tight junction responsiveness.


Assuntos
Galinhas , Íleo/imunologia , Inflamação/imunologia , Doenças das Aves Domésticas/imunologia , Técnicas de Cultura de Tecidos/veterinária , Animais , Expressão Gênica , Hidroliases/metabolismo , Íleo/patologia , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Masculino , Óxido Nítrico/metabolismo , Doenças das Aves Domésticas/patologia , RNA Mensageiro/metabolismo , Técnicas de Cultura de Tecidos/métodos
4.
Br J Nutr ; 116(12): 2030-2043, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27993179

RESUMO

For this study, threonine (Thr) deficiency was hypothesised to exacerbate the intestinal damage induced by feed withdrawal with coccidial infection because of its high obligatory requirement by the gut; two dietary Thr treatments (0·49 and 0·90 %) were applied to chicks from 0 to 21 d of age. At 13 d of age, feed was withdrawn for 24 h from one-half of birds of each dietary treatment with subsequent gavage of a 25× dose of coccidial vaccine. Overall, there were four treatments with eight replicate cages per treatment. Under combined challenge, birds fed the Thr-deficient diet had 38 % lower 13-21-d body weight gain (P≤0·05) compared with birds fed the Thr-control diet. At 21 d, the challenged group fed low Thr had higher number of oocysts (+40 %, P=0·03) and lower crypt depth (-31 %, P0·05). Overall, Thr deficiency worsened the detrimental effects of combined feed withdrawal and coccidial infection on growth performance and oocyst shedding by impairing intestinal morphology, barrier function, lymphocyte profiles and their cytokine expressions.


Assuntos
Coccidiose/veterinária , Deficiências Nutricionais/veterinária , Imunidade nas Mucosas/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Doenças das Aves Domésticas/fisiopatologia , Vacinas Protozoárias/uso terapêutico , Treonina/deficiência , Administração Oral , Animais , Restrição Calórica/efeitos adversos , Restrição Calórica/veterinária , Ceco/efeitos dos fármacos , Ceco/imunologia , Ceco/parasitologia , Ceco/patologia , Galinhas/crescimento & desenvolvimento , Coccidiose/imunologia , Coccidiose/patologia , Coccidiose/prevenção & controle , Citocinas/genética , Citocinas/metabolismo , Deficiências Nutricionais/imunologia , Deficiências Nutricionais/fisiopatologia , Dieta com Restrição de Proteínas/efeitos adversos , Dieta com Restrição de Proteínas/veterinária , Eimeria/efeitos dos fármacos , Eimeria/crescimento & desenvolvimento , Eimeria/imunologia , Eimeria/isolamento & purificação , Interações Hospedeiro-Parasita/efeitos dos fármacos , Íleo/efeitos dos fármacos , Íleo/imunologia , Íleo/parasitologia , Íleo/patologia , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/parasitologia , Mucosa Intestinal/patologia , Jejuno/efeitos dos fármacos , Jejuno/crescimento & desenvolvimento , Jejuno/imunologia , Masculino , Oocistos/efeitos dos fármacos , Oocistos/crescimento & desenvolvimento , Oocistos/imunologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Distribuição Aleatória
5.
Toxins (Basel) ; 8(8)2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27472362

RESUMO

Deoxynivalenol (DON) and fumonisins (FB) are the most frequently encountered mycotoxins produced by Fusarium species in livestock diets. The effect of subclinical doses of mycotoxins in chickens is largely unknown, and in particular the susceptibility of birds to pathogenic challenge when fed these fungal metabolites. Therefore, the present study reports the effects of DON and FB on chickens challenged with Eimeria spp, responsible for coccidiosis. Broilers were fed diets from hatch to day 20, containing no mycotoxins, 1.5 mg DON/kg, 20 mg FB/kg, or both toxins (12 pens/diet; 7 birds/pen). At day 14, six pens of birds per diet (half of the birds) were challenged with a 25×-recommended dose of coccidial vaccine, and all birds (challenged and unchallenged) were sampled 6 days later. As expected, performance of birds was strongly affected by the coccidial challenge. Ingestion of mycotoxins did not further affect the growth but repartitioned the rate of reduction (between the fraction due to the change in maintenance and feed efficiency), and reduced apparent nitrogen digestibility. Intestinal lesions and number of oocysts in the jejunal mucosa and feces of challenged birds were more frequent and intense in the birds fed mycotoxins than in birds fed control feed. The upregulation of cytokines (interleukin (IL) IL-1ß, IL-6, IL-8 and IL-10) following coccidial infection was higher in the jejunum of birds fed mycotoxins. Further, the higher intestinal immune response was associated with a higher percentage of T lymphocytes CD4⁺CD25⁺, also called Tregs, observed in the cecal tonsils of challenged birds fed mycotoxins. Interestingly, the increase in FB biomarker of exposure (sphinganine/sphingosine ratio in serum and liver) suggested a higher absorption and bioavailability of FB in challenged birds. The interaction of DON and FB was very dependent on the endpoint assessed, with three endpoints reporting antagonism, nine additivity, and two synergism. In conclusion, subclinical doses of DON and FB showed little effects in unchallenged chickens, but seem to result in metabolic and immunologic disturbances that amplify the severity of coccidiosis.


Assuntos
Ração Animal/toxicidade , Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/patogenicidade , Contaminação de Alimentos , Fumonisinas/toxicidade , Doenças das Aves Domésticas/parasitologia , Tricotecenos/toxicidade , Ração Animal/microbiologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/parasitologia , Ceco/imunologia , Ceco/parasitologia , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Coccidiose/genética , Coccidiose/imunologia , Coccidiose/parasitologia , Citocinas/genética , Citocinas/imunologia , Eimeria/imunologia , Fumonisinas/administração & dosagem , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/parasitologia , Fatores de Tempo , Tricotecenos/administração & dosagem , Ganho de Peso
6.
J Appl Toxicol ; 36(11): 1437-45, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26889939

RESUMO

To screen cost-effectively the overall toxicity of a sample, particularly in the case of food and feed ingredient quality control, a sensitive bioassay is necessary. With the wide variety of cytotoxicity assays, performance comparison between assays using different cells has become of interest. Fresh primary duck embryonic fibroblasts (DEF) were hypothesized to be a sensitive tool for in vitro cytotoxicity screening; cell viability of DEF in response to various cytotoxins was determined and compared with response of HepG2 cells. The IC50 values by the alamar blue assay in the DEF cells had a high correlation (R(2) = 0.96) with those obtained in HepG2 cells. Within the same toxin, primary DEF yielded significantly lower IC50 values than that obtained from HepG2 cells using the MTT and alamar blue assay. Additionally, primary DEF responded to all mycotoxins tested using the alamar blue assay, while HepG2 was less sensitive, particularly at short exposure times. The estimated IC50 for aflatoxin B1 , fumonisins B1 and deoxynivalenol in DEF after 72 h incubation were 3.69, 4.19 and 1.26 µg ml(-1) , respectively. Results from the current study suggest that primary DEF are more sensitive to cytotoxins and mycotoxins compared to HepG2, and thus may have great potential as an effective tool for cytotoxicity assessment. The question remains whether in vitro IC50 values can accurately predict in vivo toxicity; however, the current study accentuates the need for further attention to identify sensitive cell models for in vitro cytotoxicity screening and subsequent exploration of species-specific prediction models for in vivo toxicity. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Patos , Embrião não Mamífero/citologia , Fibroblastos/efeitos dos fármacos , Substâncias Perigosas/toxicidade , Micotoxinas/toxicidade , Testes de Toxicidade/métodos , Animais , Sobrevivência Celular/efeitos dos fármacos , Patos/embriologia , Fibroblastos/patologia , Células Hep G2 , Humanos , Cultura Primária de Células , Especificidade da Espécie
7.
Br J Nutr ; 114(2): 202-12, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26079373

RESUMO

Coccidia are protozoal parasites which compromise mucosal integrity of the intestine, potentiating poultry morbidity. The host's Zn status influences the course of infection. Therefore, two experiments were designed to determine how supplemental Zn regimens impacted jejunal and caecal immune status and Zn transporter expression. Coccivac®-B was administered weekly at ten times the recommended dose as a mild coccidial challenge (10 CV). Zn was provided through a basal diet, supplemental zinc sulfate (ZnSO4), or a supplemental 1:1 blend of ZnSO4 and Availa®-Zn (Blend). Mucosal jejunum (Expt 1) and caecal tonsils (Expt 2) were evaluated for intracellular Zn concentrations and phagocytic capacity. Messenger expression of Zn transporters ZnT5, ZnT7, Zip9 and Zip13 were investigated to determine Zn trafficking. With 10 CV, phagocytic capacity was decreased in jejunal cells by 2%. In the caecal tonsils, however, phagocytic capacity increased with challenge, with the magnitude of increase being more pronounced with higher dietary Zn (10 CV × Zn interaction; P = 0.04). Intracellular Zn within caecal tonsils was found significantly reduced with 10 CV (27%, P = 0.0001). 10 CV also resulted in an overall increase in the ratio of Zip:ZnT transporters. With the exception of Zip13 transporter expression, dietary Zn source had little impact on any of the measured cellular parameters. Thus, intestinal mucosal tissues had reductions in intracellular free Zn during coccidial challenge, which was coupled with an upregulation of measured Zip transporters. This suggests that under coccidial challenge, intestinal cells attempt to compensate for the drop in intracellular Zn.


Assuntos
Galinhas/imunologia , Dieta/veterinária , Vacinas Protozoárias/imunologia , Zinco/administração & dosagem , Ração Animal/análise , Animais , Coccídios/imunologia , Coccidiose/imunologia , Coccidiose/veterinária , Suplementos Nutricionais , Homeostase , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Jejuno/efeitos dos fármacos , Jejuno/imunologia , Sulfato de Zinco
8.
Toxins (Basel) ; 7(4): 1253-72, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25871822

RESUMO

In chickens, the effect of mycotoxins, especially fumonisins (FB), in the gastrointestinal tract (GIT) is not well documented. Thus, this study in broiler chicks determined the effects of consuming diets prepared with Fusarium verticillioides culture material containing FB on intestinal gene expression and on the sphinganine (Sa)/sphingosine (So) ratio (Sa/So; a biomarker of FB effect due to disruption of sphingolipid metabolism). Male broilers were assigned to 6 diets (6 cages/diet; 6 birds/cage) from hatch to 20 days containing 0.4, 5.6, 11.3, 17.5, 47.8, or 104.8 mg FB/kg diet. Exposure to FB altered the Sa/So ratio in all tissues analyzed, albeit to varying extents. Linear dose-responses were observed in the kidney, jejunum and cecum. The liver and the ileum were very sensitive and data fit a cubic and quadratic polynomial model, respectively. Gene expression in the small intestine revealed low but significant upregulations of cytokines involved in the pro-inflammatory, Th1/Th17 and Treg responses, especially at 10 days of age. Interestingly, the cecal tonsils exhibited a biphasic response. Unlike the sphingolipid analysis, the effects seen on gene expression were not dose dependent, even showing more effects when birds were exposed to 11.3 mg FB/kg. In conclusion, this is the first report on the disruption of the sphingolipid metabolism by FB in the GIT of poultry. Further studies are needed to reach conclusions on the biological meaning of the immunomodulation observed in the GIT, but the susceptibility of chickens to intestinal pathogens when exposed to FB, at doses lower than those that would cause overt clinical symptoms, should be addressed.


Assuntos
Fumonisinas/farmacologia , Fusarium , Íleo/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Esfingolipídeos/metabolismo , Esfingosina/análogos & derivados , Ração Animal , Animais , Galinhas , Citocinas/genética , Citocinas/metabolismo , Contaminação de Alimentos , Expressão Gênica/efeitos dos fármacos , Íleo/metabolismo , Jejuno/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Tecido Linfoide/efeitos dos fármacos , Tecido Linfoide/metabolismo , Masculino , Esfingosina/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo
9.
Poult Sci ; 94(2): 172-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25589081

RESUMO

Intestinal mucin 2 (MUC2), a major gel-forming mucin, represents a primary barrier component of mucus layers and a target site for secretory IgA. Polymeric Ig receptor (pIgR) expressed on the basolateral surface of epithelium is used to transport polymeric IgA from the lamina propria into luminal mucins to establish the first lines of intestinal defense. To determine the spatio-temporal expression of MUC2, IgA, and pIgR in broiler chickens and Pekin ducks, intestinal tissues (n=6/age) were dissected from late embryonic days up to 21 d posthatch. In the intestinal tissues, MUC2 was expressed with a rapid increase at hatching, followed by steady expression through 21 d posthatch both in chickens and ducks. IgA expression was low during the first week following hatching for both species. From the second week posthatch, IgA was rapidly expressed in the chickens, arriving at steady expression in the third week after hatching. However, in ducks, IgA expression during the 2 to 3 wk posthatch period was relatively slow. The expression of pIgR was greatly increased after hatching for both species, but its expression in ducks was relatively delayed. In addition, intestinal pIgR expression was highly correlated with MUC2 and IgA expressions in chickens but just moderately correlated in ducks. The relatively slow and late expression of IgA and pIgR as well as their moderate correlation may or may not account for the susceptibility of ducklings to mucosal pathogens at a young age.


Assuntos
Galinhas/metabolismo , Patos/metabolismo , Imunoglobulina A/metabolismo , Mucina-2/metabolismo , Receptores de Imunoglobulina Polimérica/metabolismo , Animais , Embrião de Galinha , Patos/embriologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Mucosa Intestinal/metabolismo , Mucina-2/genética , Receptores de Imunoglobulina Polimérica/genética
10.
J Sci Food Agric ; 95(1): 126-35, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24728981

RESUMO

BACKGROUND: The effects of dietary l-arginine (Arg) on immunosuppression following infectious bursal disease virus (IBDV) inoculation in broiler chickens were evaluated. The design of this study was a 5 × 2 factorial arrangement (n = 5) with five Arg concentrations (starter: 9.9, 13.9, 17.6, 21.3 and 25.3 g kg(-1) ; grower-finisher: 9.5, 13.5, 17.1, 20.1 and 23.6 g kg(-1) ) with or without IBDV inoculation (IBDV or saline inoculation at 14 days). Chickens were sampled at 2, 4 and 6 days post-inoculation (DPI) and 42 days of age. RESULTS: The IBDV inoculation decreased (P = 0.05) CD3(+) , CD4(+) , and CD8(+) T cell counts at 2 days post-inoculation (DPI) and monocyte counts at 6 DPI; and reduced (P < 0.05) bursal interleukin-1ß (IL-1ß) mRNA expression at 2 DPI and serum IL-6 concentration at 4 DPI. Increasing Arg concentration increased (P < 0.05) CD4(+) and CD8(+) T cell counts at 2 DPI, linearly increased (P = 0.05) CD3(+) T cell counts in IBDV-inoculated groups and monocyte counts in control groups at 4 DPI; increased (P < 0.05) serum IL-6 concentration in IBDV-inoculated groups at 2 DPI; and increased (P < 0.05) serum anti-IBDV antibody titres at 42 days of age. CONCLUSION: Varying concentrations of Arg supplementation attenuated IBDV inoculation induced immunosuppression via modulating circulating T cell sub-populations.


Assuntos
Arginina/administração & dosagem , Infecções por Birnaviridae/veterinária , Dieta , Tolerância Imunológica/efeitos dos fármacos , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Infecções por Birnaviridae/imunologia , Bolsa de Fabricius/química , Galinhas/imunologia , Expressão Gênica , Tolerância Imunológica/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Interleucina-1beta/genética , Interleucina-6/sangue , Contagem de Leucócitos/veterinária , Contagem de Linfócitos/veterinária , Monócitos , Doenças das Aves Domésticas/prevenção & controle , RNA Mensageiro/análise
11.
Br J Nutr ; 112(7): 1098-109, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25181320

RESUMO

The present study investigated the effects of dietary arginine (Arg) supplementation on intestinal structure and functionality in broiler chickens subjected to coccidial challenge. The present study was a randomised complete block design employing a 3 × 2 factorial arrangement (n 8) with three dietary concentrations of Arg (11·1, 13·3 and 20·2 g/kg) with or without coccidial vaccine challenge (unchallenged and coccidial challenge). On day 14, birds were orally administered with coccidial vaccine or saline. On day 21, birds were killed to obtain jejunal tissue and mucosal samples for histological, gene expression and mucosal immunity measurements. Within 7 d of the challenge, there was a decrease in body-weight gain and feed intake, and an increase in the feed:gain ratio (P< 0·05). Jejunal inflammation was evidenced by villus damage, crypt dilation and goblet cell depletion. Coccidial challenge increased mucosal secretory IgA concentration and inflammatory gene (iNOS, IL-1ß, IL-8 and MyD88) mRNA expression levels (P< 0·05), as well as reduced jejunal Mucin-2, IgA and IL-1RI mRNA expression levels (P< 0·05). Increasing Arg concentration (1) increased jejunal villus height (P< 0·05) and linearly increased jejunal crypt depth (P< 0·05); (2) quadratically increased mucosal maltase activity (P< 0·05) and linearly decreased mucosal secretory IgG concentration (P< 0·05) within the coccidiosis-challenged groups; and (3) linearly decreased jejunal Toll-like receptor 4 (TLR4) mRNA expression level (P< 0·05) within the coccidiosis-challenged groups. The mRNA expression of mechanistic target of rapamycin (mTOR) complex 1 pathway genes (mTOR and RPS6KB1) and the anti-apoptosis gene Bcl-2 quadratically responded to increasing dietary Arg supplementation (P< 0·05). These results indicate that dietary Arg supplementation attenuates intestinal mucosal disruption in coccidiosis-challenged chickens probably through suppressing TLR4 and activating mTOR complex 1 pathways.


Assuntos
Arginina/administração & dosagem , Galinhas , Coccídios/imunologia , Gastroenterite/veterinária , Doenças das Aves Domésticas/imunologia , Vacinas Protozoárias/efeitos adversos , Animais , Galinhas/crescimento & desenvolvimento , Coccidiose/prevenção & controle , Coccidiose/veterinária , Suplementos Nutricionais , Gastroenterite/imunologia , Gastroenterite/prevenção & controle , Expressão Gênica/efeitos dos fármacos , Genes bcl-2/genética , Imunoglobulina A Secretora/análise , Imunoglobulina G/análise , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Jejuno/química , Jejuno/patologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , RNA Mensageiro/análise , Serina-Treonina Quinases TOR/genética , Receptor 4 Toll-Like/genética
12.
Br J Nutr ; 111(8): 1394-404, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24330949

RESUMO

In the present study, two experiments were conducted to investigate the effect of dietary L-arginine (Arg) supplementation on the inflammatory response and innate immunity of broiler chickens. Expt 1 was designed as a 2 × 3 factorial arrangement (n 8 cages/treatment; n 6 birds/cage) with three dietary Arg concentrations (1.05, 1.42 and 1.90%) and two immune treatments (injection of lipopolysaccharide (LPS) or saline) given at an interval of 48 h between 14 and 21 d of age. In Expt 2, correlation between dietary Arg concentration (0.99, 1.39, 1.76, 2.13 or 2.53%) and percentage of circulating B cells (percentage of circulating lymphocytes) was determined. In Expt 1, LPS injection decreased body-weight gain and feed intake and increased feed conversion ratio of the challenged broilers (14-21 d; P< 0.05). LPS injection suppressed (P< 0.05) the percentages of splenic CD11+ and B cells (percentages of splenic lymphocytes) and phagocytic activity of splenic heterophils and macrophages; Arg supplementation linearly decreased the percentages of CD11+, CD14+ and B cells in the spleen (P< 0.10). LPS injection increased (P< 0.05) the expression of IL-1ß and IL-6 mRNA in the spleen and caecal tonsils. Arginine supplementation decreased (P< 0.05) the expression of IL-1ß, Toll-like receptor 4 (TLR4) and PPAR-γ mRNA in the spleen and IL-1ß, IL-10, TLR4 and NF-κB mRNA in the caecal tonsils. In Expt 2, increasing dietary Arg concentrations linearly and quadratically reduced the percentage of circulating B cells (P< 0.01). Collectively, Arg supplementation attenuated the overexpression of pro-inflammatory cytokines probably through the suppression of the TLR4 pathway and CD14+ cell percentage. Furthermore, excessive Arg supplementation (1.76%) suppressed the percentages of circulating and splenic B cells.


Assuntos
Arginina/uso terapêutico , Galinhas/imunologia , Citocinas/metabolismo , Suplementos Nutricionais , Imunidade Inata/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Inflamação/tratamento farmacológico , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antígenos CD/metabolismo , Arginina/farmacologia , Ceco/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Sistema Imunitário/citologia , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/veterinária , Interleucinas/metabolismo , Lipopolissacarídeos , Masculino , Carne , NF-kappa B/genética , NF-kappa B/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Fagocitose/efeitos dos fármacos , RNA Mensageiro/metabolismo , Baço/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Ganho de Peso/efeitos dos fármacos
13.
Toxins (Basel) ; 5(2): 396-430, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23430606

RESUMO

Mycotoxins are secondary metabolites of fungi that can cause serious health problems in animals, and may result in severe economic losses. Deleterious effects of these feed contaminants in animals are well documented, ranging from growth impairment, decreased resistance to pathogens, hepato- and nephrotoxicity to death. By contrast, data with regard to their impact on intestinal functions are more limited. However, intestinal cells are the first cells to be exposed to mycotoxins, and often at higher concentrations than other tissues. In addition, mycotoxins specifically target high protein turnover- and activated-cells, which are predominant in gut epithelium. Therefore, intestinal investigations have gained significant interest over the last decade, and some publications have demonstrated that mycotoxins are able to compromise several key functions of the gastrointestinal tract, including decreased surface area available for nutrient absorption, modulation of nutrient transporters, or loss of barrier function. In addition some mycotoxins facilitate persistence of intestinal pathogens and potentiate intestinal inflammation. By contrast, the effect of these fungal metabolites on the intestinal microbiota is largely unknown. This review focuses on mycotoxins which are of concern in terms of occurrence and toxicity, namely: aflatoxins, ochratoxin A and Fusarium toxins. Results from nearly 100 published experiments (in vitro, ex vivo and in vivo) were analyzed with a special attention to the doses used.


Assuntos
Intestinos/efeitos dos fármacos , Micotoxinas/toxicidade , Animais , Alimentos , Humanos , Absorção Intestinal , Intestinos/microbiologia , Intestinos/fisiologia
14.
PLoS One ; 8(1): e53781, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23349743

RESUMO

Intestinal mucin 2 (MUC2) encodes a heavily glycosylated, gel-forming mucin, which creates an important protective mucosal layer along the gastrointestinal tract in humans and other species. This first line of defense guards against attacks from microorganisms and is integral to the innate immune system. As a first step towards characterizing the innate immune response of MUC2 in different species, we report the cloning of a full-length, 11,359 bp chicken MUC2 cDNA, and describe the genomic organization and functional annotation of this complex, 74.5 kb locus. MUC2 contains 64 exons and demonstrates distinct spatiotemporal expression profiles throughout development in the gastrointestinal tract; expression increases with gestational age and from anterior to posterior along the gut. The chicken protein has a similar domain organization as the human orthologue, with a signal peptide and several von Willebrand domains in the N-terminus and the characteristic cystine knot at the C-terminus. The PTS domain of the chicken MUC2 protein spans ∼1600 amino acids and is interspersed with four CysD motifs. However, the PTS domain in the chicken diverges significantly from the human orthologue; although the chicken domain is shorter, the repetitive unit is 69 amino acids in length, which is three times longer than the human. The amino acid composition shows very little similarity to the human motif, which potentially contributes to differences in the innate immune response between species, as glycosylation across this rapidly evolving domain provides much of the musical barrier. Future studies of the function of MUC2 in the innate immune response system in chicken could provide an important model organism to increase our understanding of the biological significance of MUC2 in host defense and highlight the potential of the chicken for creating new immune-based therapies.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/genética , Regulação da Expressão Gênica no Desenvolvimento , Mucosa Intestinal/metabolismo , Intestinos/crescimento & desenvolvimento , Anotação de Sequência Molecular , Mucina-2/genética , Processamento Alternativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Genômica , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Mucina-2/química , Homologia de Sequência de Aminoácidos
15.
PLoS One ; 6(7): e22691, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21829480

RESUMO

Trefoil factors are essential healing initiators participating in mucosal reconstitution and tissue morphogenesis, especially on the surfaces of the gastrointestinal tract. This family has been cloned and characterized predominantly from mammals and amphibians. Avian species ingest stone and grit to help digest food, which may expose their gut to severe physical conditions. To further the understanding of the function of the TFF gene family across species, we undertook this research to clone, sequence, and characterize the spatio-temporal expression patterns of chicken TFF2 (ChTFF2) cDNA. Bioinformatics analysis of the promoter region and deduced amino acid sequence demonstrated that ChTFF2 contained unique characteristics; specifically the chicken promoter has multiple start sites and the protein contains a series of Lys-Lys-Val repeats. Unlike mammals, where TFF2 is detected primarily in the stomach, and occasionally in the proximal duodenum, chicken TFF2 transcripts are found throughout the gastrointestinal tract, with major expression sites in the glandular and muscular stomach as well as evident expression in the colon, small intestine, cecal tonsil and crop. Temporal analysis of intestinal ChTFF2 transcripts by quantitative RT-PCR showed high levels in embryos and a trend of constant expression during embryonic and post-hatch development, with a reduction occurring around hatch. Phylogenetic analysis highlighted the conservation of TFF proteins and functional divergence of trefoil domains, which suggest a transitional role in the bird during evolution.


Assuntos
Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Evolução Biológica , Peptídeos/genética , Peptídeos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Galinhas , Clonagem Molecular , Dados de Sequência Molecular , Filogenia , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Fator Trefoil-2
16.
J Agric Food Chem ; 54(5): 1792-6, 2006 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-16506835

RESUMO

Five copper (Cu) sources were studied at pH 2.5, 5.5, and 6.5 to determine how Cu affects phytate phosphorus (PP) hydrolysis by phytase at concentrations up to 500 mg/kg diet (60 min, 40-41 degrees C). Subsequently, Cu solubility with and without sodium phytate was measured. Adding Cu inhibited PP hydrolysis at pH 5.5 and pH 6.5 (P < 0.05). This inhibition was greater with higher concentrations of Cu. Tri-basic copper chloride and copper lysinate inhibited PP hydrolysis much less than copper sulfate pentahydrate, copper chloride, and copper citrate (P < 0.05). A strong negative relationship was observed between PP hydrolysis and soluble Cu at pH 5.5 (r = -0.76, P < 0.0001) and 6.5 (r = -0.54, P < 0.0001). In conclusion, pH, Cu concentration, and source influenced PP hydrolysis by phytase in vitro and were related to the amount of soluble Cu and the formation of insoluble copper-phytin complexes.


Assuntos
6-Fitase/metabolismo , Cobre/análise , Cobre/farmacologia , Fósforo/metabolismo , Ácido Fítico/metabolismo , Cobre/química , Concentração de Íons de Hidrogênio , Hidrólise , Solubilidade
17.
J Environ Qual ; 34(2): 563-71, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15758109

RESUMO

The effect of dietary non-phytin phosphorus (NPP) and phytase (PHY) concentration on total phosphorus (TP) and water-soluble phosphorus (WSP) excretion was determined. Diets tested in broiler experiments were: National Research Council nutrient requirements for non-phytin phosphorus (NRC), NRC + PHY, reduced non-phytin phosphorus (RED), and RED + PHY. Turkey and swine experiment diets included NRC, RED, and RED + PHY. For all experiments, except broiler Experiment 1, excreta were: (i) boiled, antibiotic added, then frozen; (ii) boiled, antibiotic added, incubated (37 degrees C for 72 h), then frozen; and (iii) incubated, boiled, antibiotic added, then frozen. In Experiment 1, excreta were collected and frozen or incubated for 24 or 48 h. In broiler Experiment 1, WSP was not affected by phytase but increased with post-excretion incubation. In a broiler Experiment 2, reducing NPP resulted in reduced excreta TP and WSP (11.3 to 8.3 and 5.3 to 2.7 g kg(-1)). Feeding RED + PHY diets resulted in less TP and WSP (7.6 and 0.6 g kg(-1)) as compared with NRC + PHY (11.2 and 3.9 g kg(-1), Experiment 3). Incubation resulted in increased WSP, irrespective of phytase addition such that WSP as a percent of TP was similar among treatments. Addition of antibiotics before incubation prevented the increase in WSP. Similar results were observed with turkey and swine. Therefore, when phytase is used properly (i.e., with a simultaneous reduction of NPP), WSP or WSP as a percent of TP are not affected. The increase in WSP as a percent of TP post-excretion is a function of excreta microbial activity and not dietary phytase addition.


Assuntos
6-Fitase/farmacologia , Ração Animal , Esterco , Fósforo/química , Fósforo/metabolismo , Criação de Animais Domésticos , Animais , Aves Domésticas , Solubilidade , Suínos , Poluição da Água/prevenção & controle
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