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1.
Microbiome ; 9(1): 38, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531080

RESUMO

BACKGROUND: Microbial endocrinology, which is the study of neuroendocrine-based interkingdom signaling, provides a causal mechanistic framework for understanding the bi-directional crosstalk between the host and microbiome, especially as regards the effect of stress on health and disease. The importance of the cecal microbiome in avian health is well-recognized, yet little is understood regarding the mechanisms underpinning the avian host-microbiome relationship. Neuroendocrine plasticity of avian tissues that are focal points of host-microbiome interaction, such as the gut and lung, has likewise received limited attention. Avian in vivo models that enable the study of the neuroendocrine dynamic between host and microbiome are needed. As such, we utilized Japanese quail (Coturnix japonica) that diverge in corticosterone response to stress to examine the relationship between stress-related neurochemical concentrations at sites of host-microbe interaction, such as the gut, and the cecal microbiome. RESULTS: Our results demonstrate that birds which contrast in corticosterone response to stress show profound separation in cecal microbial community structure as well as exhibit differences in tissue neurochemical concentrations and structural morphologies of the gut. Changes in neurochemicals known to be affected by the microbiome were also identified in tissues outside of the gut, suggesting a potential relationship in birds between the cecal microbiome and overall avian physiology. CONCLUSIONS: The present study provides the first evidence that the structure of the avian cecal microbial community is shaped by selection pressure on the bird for neuroendocrine response to stress. Identification of unique region-dependent neurochemical changes in the intestinal tract following stress highlights environmental stressors as potential drivers of microbial endocrinology-based mechanisms of avian host-microbiome dialogue. Together, these results demonstrate that tissue neurochemical concentrations in the avian gut may be related to the cecal microbiome and reveal the Japanese quail as a novel avian model in which to further examine the mechanisms underpinning these relationships. Video abstract.


Assuntos
Coturnix/metabolismo , Coturnix/microbiologia , Sistema Endócrino/metabolismo , Sistema Endócrino/microbiologia , Interações entre Hospedeiro e Microrganismos , Microbiota/fisiologia , Animais , Ceco/microbiologia , Masculino , Modelos Biológicos
2.
Am J Physiol Heart Circ Physiol ; 319(3): H705-H721, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32762560

RESUMO

Myeloperoxidase (MPO)-derived hypochlorous (HOCl) reacts with membrane plasmalogens to yield α-chlorofatty aldehydes such as 2-chlorofatty aldehyde (2-ClFALD) and its metabolite 2-chlorofatty acid (2-ClFA). Recent studies showed that 2-ClFALD and 2-ClFA serve as mediators of the inflammatory responses to sepsis by as yet unknown mechanisms. Since no scavenger for chlorinated lipids is available and on the basis of the well-established role of the MPO/HOCl/chlorinated lipid axis in inflammatory responses, we hypothesized that treatment with MPO inhibitors (N-acetyl lysyltyrosylcysteine amide or 4-aminobenzoic acid hydrazide) would inhibit inflammation and proinflammatory mediator expression induced by cecal ligation and puncture (CLP). We used intravital microscopy to quantify in vivo inflammatory responses in Sham and CLP rats with or without MPO inhibition. Small intestines, mesenteries, and lungs were collected to assess changes in MPO-positive staining and lung injury, respectively, as well as free 2-ClFA and proinflammatory mediators levels. CLP caused neutrophil infiltration, 2-ClFA generation, acute lung injury, leukocyte-/platelet-endothelium interactions, mast cell activation (MCA), plasminogen activator inhibitor-1 (PAI-1) production, and the expression of several cytokines, chemokines, and vascular endothelial growth factor, changes that were reduced by MPO inhibition. Pretreatment with a PAI-1 inhibitor or MC stabilizer prevented CLP-induced leukocyte-endothelium interactions and MCA, and abrogated exogenous 2-ClFALD-induced inflammatory responses. Thus, we provide evidence that MPO instigates these inflammatory changes in CLP and that chlorinated lipids may serve as a mechanistic link between the enzymatic activity of MPO and PAI-1- and mast cell-dependent adhesive interactions, providing a rationale for new therapeutic interventions in sepsis.NEW & NOTEWORTHY Using two distinct myeloperoxidase (MPO) inhibitors, we show for the first time that MPO plays an important role in producing increases in free 2-chlorofatty aldehyde (2-ClFALD)-a powerful proinflammatory chlorinated lipid in plasma and intestine-a number of cytokines and other inflammatory mediators, leukocyte and platelet rolling and adhesion in postcapillary venules, and lung injury in a cecal ligation and puncture model of sepsis. In addition, the use of a plasminogen activator inhibitor-1 (PAI-1) inhibitor or a mast cell stabilizer prevented inflammatory responses in CLP-induced sepsis. PAI-1 inhibition also prevented the proinflammatory responses to exogenous 2-ClFALD superfusion. Thus, our study provides some of the first evidence that MPO-derived free 2-ClFA plays an important role in CLP-induced sepsis by a PAI-1- and mast cell-dependent mechanism.


Assuntos
Ceco/microbiologia , Ácidos Graxos/metabolismo , Ácido Hipocloroso/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/enzimologia , Peroxidase/metabolismo , Sepse/enzimologia , Aldeídos/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Ceco/cirurgia , Citocinas/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inflamação/imunologia , Inflamação/microbiologia , Inflamação/prevenção & controle , Mediadores da Inflamação/antagonistas & inibidores , Intestino Delgado/enzimologia , Intestino Delgado/imunologia , Ligadura , Pulmão/enzimologia , Pulmão/imunologia , Mastócitos/enzimologia , Mastócitos/imunologia , Mesentério/enzimologia , Mesentério/imunologia , Peroxidase/antagonistas & inibidores , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Punções , Ratos Sprague-Dawley , Sepse/imunologia , Sepse/microbiologia , Sepse/prevenção & controle , Transdução de Sinais
3.
PLoS One ; 15(8): e0237541, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32834007

RESUMO

There is growing interest in exploring the chickens' intestinal microbiota and understanding its interactions with the host. The objective is to optimize this parameter in order to increase the productivity of farm animals. With the goal to isolate candidate probiotic strains, specific culturomic methods were used in our study to culture commensal bacteria from 7-days old chicks raised in two farms presenting long history of high performance. A total of 347 isolates were cultured, corresponding to at least 64 species. Among the isolates affiliated to the Firmicutes, 26 had less than 97% identity of their partial 16S sequence with that of the closest described species, while one presented less than 93% identity, thus revealing a significant potential for new species in this ecosystem. In parallel, and in order to better understand the differences between the microbiota of high-performing and low-performing animals, caecal contents of animals collected from these two farms and from a third farm with long history of low performance were collected and sequenced. This compositional analysis revealed an enrichment of Faecalibacterium-and Campylobacter-related sequences in lower-performing animals whereas there was a higher abundance of enterobacteria-related sequences in high-performing animals. We then investigated antibiosis activity against C. jejuni ATCC 700819 and C. jejuni field isolate as a first phenotypic trait to select probiotic candidates. Antibiosis was found to be limited to a few strains, including several lactic acid bacteria, a strain of Bacillus horneckiae and a strain of Escherichia coli. The antagonist activity depended on test conditions that mimicked the evolution of the intestinal environment of the chicken during its lifetime, i.e. temperature (37°C or 42°C) and oxygen levels (aerobic or anaerobic conditions). This should be taken into account according to the stage of development of the animal at which administration of the active strain is envisaged.


Assuntos
Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Ceco/microbiologia , Galinhas/microbiologia , Microbioma Gastrointestinal , Doenças das Aves Domésticas/epidemiologia , Envelhecimento , Animais , Campylobacter/genética , Técnicas de Cultura de Células/métodos , Fazendas , Doenças das Aves Domésticas/microbiologia
4.
Appl Environ Microbiol ; 86(21)2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32859592

RESUMO

Salmonella enterica serovar Typhimurium is a prevalent incitant of enteritis in human beings and nonhuman animals. It has been proposed that host defense responses incited by Salmonella allow the bacterium to overcome colonization resistance. Piglets (n = 24) were orally inoculated with S. enterica serovar Typhimurium DT104 or buffer alone, and the host and microbial responses were temporally examined at the acute (2 days postinoculation [dpi]), subacute (6 dpi), and recovery (10 dpi) stages of salmonellosis. At the acute stage of disease, body temperatures were elevated, and feed consumption and weight gain were reduced. The densities of Salmonella associated with the gut mucosa decreased over time, with higher densities of the bacterium in the ileum and the large intestine. Moreover, substantive histopathological changes were observed as a function of time, with prominent epithelial injury and neutrophil infiltration observed at 2 dpi. Correspondingly, a variety of host metrics were temporally affected in piglets with salmonellosis (e.g., TNFα, IFNγ, PR39, ßD2, iNOS, IL8, REGIIIγ). The enteric microbiota was characterized using culture-independent and -dependent methods in concert, and taxon- and location-specific changes to the microbiota were observed in infected piglets. Bacteroides spp. (e.g., Bacteroides uniformis, Bacteroides fragilis), Streptococcus spp. (e.g., Streptococcus gallolyticus), and various Gammaproteobacteria were highly associated with inflamed tissues, while bacteria within the Ruminococcaceae and Veillonellaceae families were mainly associated with healthy mucosae. In conclusion, the study findings showed that S Typhimurium incited temporal and spatial modifications to the swine autochthonous microbiota, and to host defense responses, that were consistent with overcoming colonization resistance to incite salmonellosis in swine.IMPORTANCE Limited information is available on host and enteric microbiota responses incited by Salmonella enterica serovar Typhimurium in swine and on possible mechanisms by which the bacterium overcomes colonization resistance to incite salmonellosis. Temporal characterization of a variety of host metrics in piglets (e.g., physiological, histopathological, and immunological) showed the importance of studying the progression of salmonellosis. A number of host responses integrally associated with disease development were identified. Utilization of next-generation sequence analysis to characterize the enteric microbiota was found to lack sufficient resolution; however, culture-dependent and -independent methods in combination identified taxon- and location-specific changes to bacterial communities in infected piglets. The study identified bacterial and host responses associated with salmonellosis, which will be beneficial in understanding colonization resistance and in the development of effective alternatives to antibiotics to mitigate salmonellosis.


Assuntos
Ceco/microbiologia , Colo/microbiologia , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos/imunologia , Íleo/microbiologia , Salmonella typhimurium/fisiologia , Animais , Ceco/imunologia , Colo/imunologia , Íleo/imunologia , Masculino , Distribuição Aleatória , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Fatores de Tempo
5.
J Anim Sci ; 98(7)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32687166

RESUMO

Feed is the greatest cost of animal production, so reducing it is critical to increase producer profits. In ruminants, the microbial population within the gastrointestinal tract (GIT) is critical to nutrient digestion and absorption in both the rumen and the hindgut. The objective of this study was to determine the bacterial taxonomic profile of the rumen, cecum, and feces of feedlot steers at slaughter in order to link feed efficiency and the GIT bacterial populations from these three locations. Twenty commercial Angus steers were selected and divided into two groups according to their residual feed intake (RFI) classification determined during the feedlot-finishing period: high-RFI (n = 10) and low-RFI (n = 10). After the ruminal, cecal, and fecal samples were collected at slaughter, DNA extraction and 16S rRNA gene sequencing were performed on them to determine their bacterial composition. One-way ANOVA was performed on the animal performance data, alpha diversities, and bacterial abundances using RFI classification as the fixed effect. Overall, the ruminal bacterial population was the most different in terms of taxonomic profile compared with the cecal and fecal populations as revealed by beta diversity analysis (P < 0.001). Moreover, bacterial richness (Chao1) was greatest (P = 0.01) in the rumen of the high-RFI group compared with the low-RFI group. In contrast, bacterial richness and diversity in the intestinal environment showed that Chao1 was greater (P = 0.01) in the cecum, and the Shannon diversity index was greater in both the cecum and feces of low-RFI compared with high-RFI steers (P = 0.01 and P < 0.001, respectively). Ruminococcaceae was more abundant in the low-RFI group in the cecum and feces (P = 0.01); fecal Bifidobacteriaceae was more abundant in high-RFI steers (P = 0.03). No correlations (P ≥ 0.13) between any ruminal bacterial family and RFI were detected; however, Ruminococcaceae, Mogibacteriaceae, Christensenellaceae, and BS11 were negatively correlated with RFI (P < 0.05) in the cecum and feces. Succinivibrionaceae in the cecum was positively correlated with RFI (P = 0.05), and fecal Bifidobacteriaceae was positively correlated with RFI (P = 0.03). Results collectively indicate that in addition to the ruminal bacteria, the lower gut bacterial population has a significant impact on feed efficiency and nutrient utilization in feedlot steers; therefore, the intestinal bacteria should also be considered when examining the basis of ruminant feed efficiency.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Ceco/microbiologia , Dieta/veterinária , Fezes/microbiologia , Rúmen/microbiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bactérias/classificação , Trato Gastrointestinal , Masculino , Microbiota , RNA Ribossômico 16S
6.
J Vis Exp ; (161)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32716381

RESUMO

Candida albicans hyphal morphogenesis in the gastrointestinal (GI) tract is tightly controlled by various environmental signals, and plays an important role in the dissemination and pathogenesis of this opportunistic fungal pathogen. However, methods to visualize fungal hyphae in the GI tract in vivo are challenging which limits the understanding of environmental signals in controlling this morphogenesis process. The protocol described here demonstrates a novel ex vivo method for visualization of hyphal morphogenesis in gut homogenate extracts. Using an ex vivo assay, this study demonstrates that cecal contents from antibiotic treated mice, but not from untreated control mice, promote C. albicans hyphal morphogenesis in the gut content. Further, adding back specific groups of gut metabolites to the cecal contents from antibiotic-treated mice differentially regulates hyphal morphogenesis ex vivo. Taken together, this protocol represents a novel method to identify and investigate the environmental signals that control C. albicans hyphal morphogenesis in the GI tract.


Assuntos
Bioensaio/métodos , Candida albicans/crescimento & desenvolvimento , Trato Gastrointestinal/microbiologia , Hifas/crescimento & desenvolvimento , Morfogênese , Animais , Candida albicans/efeitos dos fármacos , Ceco/microbiologia , Cefoperazona/farmacologia , Feminino , Proteínas Fúngicas/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Hifas/efeitos dos fármacos , Masculino , Metaboloma/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Morfogênese/efeitos dos fármacos
7.
PLoS One ; 15(6): e0232831, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497096

RESUMO

The burden of enteric pathogens in poultry is growing after the ban of antibiotic use in animal production. Organic acids gained attention as a possible alternative to antibiotics due to their antimicrobial activities, improved nutrient metabolism and performance. The current study was conducted to evaluate the effectiveness of organic acid blend on broilers cecal microbiota, histomorphometric measurements, and short-chain fatty acid production in Salmonella enterica serovar Typhimurium challenge model. Birds were divided into four treatments, including a negative control, positive control challenged with S. Typhimurium, group supplemented with an organic acid blend, and birds supplemented with organic acid blend and Salmonella challenged. Results illustrate significant differences in feed conversion ratios and production efficiency factor between treatment groups, however, the influence of organic acid supplement was marginal. Organic acid blend significantly increased cecal acetic and butyric acids concentrations when compared to unsupplemented groups and resulted in minor alterations of intestinal bacterial communities.


Assuntos
Acetatos/metabolismo , Ração Animal , Butiratos/metabolismo , Galinhas/microbiologia , Suplementos Nutricionais , Ácidos Graxos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Doenças das Aves Domésticas/terapia , Salmonelose Animal/terapia , Salmonella typhimurium/efeitos dos fármacos , Animais , Ceco/microbiologia , Galinhas/metabolismo , Ácidos Graxos/administração & dosagem , Ácidos Graxos Voláteis/administração & dosagem , Ácidos Graxos Voláteis/farmacologia , Íleo/metabolismo , Íleo/ultraestrutura , Mananas/administração & dosagem , Microvilosidades/ultraestrutura , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/metabolismo
8.
Am J Physiol Gastrointest Liver Physiol ; 319(2): G157-G169, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32508155

RESUMO

The gut microbiome has the potential to create or modify xenometabolites (i.e., nonhost-derived metabolites) through de novo synthesis or modification of exogenous and endogenous compounds. While there are isolated examples of xenometabolites influencing host health and disease, wide-scale characterization of these metabolites remains limited. We developed a metabolomics platform ("XenoScan") using liquid chromatography-mass spectrometry to characterize a range of known and suspected xenometabolites and their derivatives. This assay currently applies authentic standards for 190 molecules, enriched for metabolites of microbial origin. As a proof-of-principle, we characterized the cecal content xenometabolomics profile in adult male lean Sprague-Dawley (LSD) and University of California, Davis type 2 diabetes mellitus (UCD-T2DM) rats at different stages of diabetes. These results were correlated to specific bacterial species generated via shotgun metagenomic sequencing. UCD-T2DM rats had a unique xenometabolite profile compared with LSD rats, regardless of diabetes status, suggesting that at least some of the variation is associated with host genetics. Furthermore, modeling approaches revealed that several xenometabolites discriminated UCD-T2DM rats at early stages of diabetes versus those at 3 mo postdiabetes onset. Several xenometabolite hubs correlated with specific bacterial species in both LSD and UCD-T2DM rats. For example, indole-3-propionic acid negatively correlated with species within the Oscillibacter genus in UCD-T2DM rats considered to be prediabetic or recently diagnosed diabetic, in contrast to gluconic acid and trimethylamine, which were positively correlated with Oscillibacter species. The application of a xenometabolite-enriched metabolomics assay in relevant milieus will enable rapid identification of a wide variety of gut-derived metabolites, their derivatives, and their potential biochemical origins of xenometabolites in relationship to host gastrointestinal microbial ecology.NEW & NOTEWORTHY We debut a liquid chromatography-mass spectrometry (LC/MS) platform called the XenoScan, which is a metabolomics platform for xenometabolites (nonself-originating metabolites). This assay has 190 in-house standards with the majority enriched for microbe-derived metabolites. As a proof-of-principle, we used the XenoScan to discriminate genetic differences from cecal samples associated with different rat lineages, in addition to characterizing diabetes progression in rat model of type 2 diabetes. Complementing microbial sequencing data with xenometabolites uncovered novel microbial metabolism in targeted organisms.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Microbioma Gastrointestinal/fisiologia , Metabolômica , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Ceco/microbiologia , Masculino , Redes e Vias Metabólicas , Ratos , Ratos Sprague-Dawley
9.
PLoS One ; 15(6): e0225921, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492021

RESUMO

Probiotics have become increasingly popular in the poultry industry as a promising nutritional intervention to promote the modulation of intestinal microbial communities and their metabolic activities as a means of improving health and performance. This study aimed to determine the influence of different probiotic formulations on the taxonomic and metabolic profiling of cecal microbial communities, as well as to define associations between cecal microbiota and growth parameters in 21 and 42-day-old broilers. Probiotics investigated included a synbiotic (SYNBIO), a yeast-based probiotic (YEAST), and three single-strain formulations of spore-forming Bacillus amyloliquefaciens (SINGLE1), B. subtilis (SINGLE2) and B. licheniformis (SINGLE3). Dietary inclusion of SYNBIO, YEAST, SINGLE2, and SINGLE3 into the diets supported a significant stimulation of BW and BWG by 7 days of age. Besides, SYNBIO reduced the overall mortality rate by 42d (p<0.05). No significant variation was observed among different probiotic-based formulations for cecal microbiota composition. However, there was a treatment-specific effect on the metabolic profiles, with a particular beneficial metabolic adaptation by the microbiota when supplemented by SYNBIO and SINGLE2. Furthermore, the population of Lactobacillales was identified to be strongly associated with lower Enterobacteriales colonization, higher BW means, and lower mortality rate of growing broilers. Overall, the results emphasize that probiotic supplementation may enhance the microbial energy metabolism in the ceca of young broilers.


Assuntos
Ceco/efeitos dos fármacos , Ceco/microbiologia , Galinhas , Microbiota/efeitos dos fármacos , Probióticos/farmacologia , Animais , Masculino
10.
Chemosphere ; 258: 127255, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554004

RESUMO

Trifluoromethanesulfonic acid (TFMS) is the shortest chain perfluorinated compound. Recently, it has been identified as a persistent and mobile organic chemical with a maximum concentration of 1 µg/L in the environment. However, its toxicological mechanism remains unclear. In this study, to evaluate the liver and intestinal toxicity of TFMS in mammals, male mice were orally exposed to 0, 1, 10 and 100 µg/kg for 12 weeks. Our results showed that TFMS exposure reduced the epididymal fat weight in mice, caused the decrease of serum and liver triglyceride (TG) level and the increase of serum low density lipoprotein (LDL) level. Also, we observed the inflammatory cell infiltration in the liver of mice exposed to 10 µg/kg and 100 µg/kg TFMS, which was coupled with the increased mRNA expression levels of inflammatory factors such as COX2, TNF-α, IL-1ß in the liver. In addition, the mRNA expression levels of lipid metabolism-related genes (PPAR-α, ACOX, SCD1, PPAR-γ, etc.) were significantly decreased in the liver of mice after exposure to both doses of TFMS. We also found TFMS exposure caused the imbalance of cecal gut microbiota and change of cecal microbiota diversity. KEGG pathway predictions showed that the exposure of 100 µg/kg TFMS changed the synthesis and degradation of ketone bodies, benzoate degradation and several other metabolic pathways. Our findings indicated that TFMS exposure disturbed the liver lipid metabolism possibly via altering the gut microbiota.


Assuntos
Poluentes Ambientais/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Mesilatos/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Ceco/efeitos dos fármacos , Ceco/microbiologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Disbiose , Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Triglicerídeos/sangue
11.
PLoS One ; 15(5): e0232905, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442163

RESUMO

Antibiotic administration can be a cause of gastrointestinal disease in horses, creating a disruption in the normal population and function of bacteria found in the hindgut. The objective of this study was to describe the changes in the cecal and fecal microbiomes and metabolomes of clinically healthy horses before and after metronidazole administration. Metronidazole (15 mg/kg BID PO) was given to five horses with cecal cannulas. The study was suspended on Day 3 due to adverse gastrointestinal effects. Cecal and fecal samples were obtained before (Days minus52, m28, m14, and 0) and after (Days 7, 14, 28, and 52) metronidazole administration. DNA was extracted from the cecal and fecal samples, and 16S rRNA genes were sequenced. Richness and evenness indices were significantly decreased by metronidazole administration in both cecal and fecal samples, but the overall composition was only significantly changed in fecal samples on Day 3 (ANOSIM, p = 0.008). The most dominant phyla were Bacteroidetes and Firmicutes in all groups examined. In fecal samples, significant changes of the phyla Actinobacteria, Spirochaetes, Lentisphaerae, and Verrucomicrobia occurred on Day 3, which correlated with clinical signs of gastrointestinal disease. The metabolome was characterized by mass spectrometry-based methods and only named metabolites were included in the analysis. Fecal, but not cecal, metabolites were significantly affected by metronidazole. The fecal metabolites affected represent diverse metabolic pathways, such as the metabolism of amino acids, carbohydrates, lipids, nucleic acids and cofactors and vitamins. Metronidazole administration has potential to cause adverse effects in horses, alters the bacterial composition of the horse's cecal and fecal content, and the metabolome of fecal samples.


Assuntos
Antibacterianos/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Cavalos , Metaboloma/efeitos dos fármacos , Metronidazol/administração & dosagem , Animais , Biodiversidade , Ceco/efeitos dos fármacos , Ceco/metabolismo , Ceco/microbiologia , Fezes/química , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Cavalos/metabolismo , Cavalos/microbiologia , Masculino , RNA Ribossômico 16S
12.
Sci Rep ; 10(1): 8183, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424118

RESUMO

In preceding efforts, we demonstrated that antibiotic (ABX) cocktail-mediated perturbations of the gut microbiome in two independent transgenic lines, termed APPSWE/PS1ΔE9 and APPPS1-21, leads to a reduction in Aß deposition in male mice. To determine whether these observed reductions of cerebral Aß amyloidosis are specific to any individual antibiotic or require the synergistic effects of several antibiotics, we treated male APPPS1-21 transgenic mice with either individual ABX or an ABX cocktail and assessed amyloid deposition. Specifically, mice were subject to oral gavage with high dose kanamycin, gentamicin, colistin, metronidazole, vancomycin, individually or in a combination (ABX cocktail) from postnatal days (PND) 14 to 21, followed by ad libitum, low-dose individual ABX or ABX cocktail in the drinking water until the time of sacrifice. A control group was subject to gavage with water from PND 14 to 21 and received drinking water till the time of sacrifice. At the time of sacrifice, all groups showed distinct cecal microbiota profiles with the highest differences between control and ABX cocktail-treated animals. Surprisingly, only the ABX cocktail significantly reduced brain Aß amyloidosis compared to vehicle-treated animals. In parallel studies, and to assess the potential exposure of ABX to the brain, we quantified the levels of each ABX in the brain by liquid chromatography-mass spectrometry (LC-MS) at PND 22 or at 7 weeks of age. With the exception of metronidazole (which was observed at less than 3% relative to the spiked control brains), we were unable to detect the other individual ABX in brain homogenates. Our findings suggest that synergistic alterations of gut microbial consortia, rather than individual antimicrobial agents, underlie the observed reductions in brain amyloidosis.


Assuntos
Doença de Alzheimer/complicações , Amiloidose/complicações , Amiloidose/microbiologia , Antibacterianos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Ceco/efeitos dos fármacos , Ceco/microbiologia , Masculino , Camundongos , Camundongos Transgênicos
13.
PLoS One ; 15(5): e0225871, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32369478

RESUMO

The potential of probiotics to manipulate the intestinal microbial ecosystem toward commensal bacteria growth offers great opportunity for enhancing health and performance in poultry. This study aimed to evaluate the efficacy of five probiotic-based formulations in modulating cecal microbiota in broilers at 21 and 42 days of age. Probiotics investigated included a synbiotic (SYNBIO), a yeast (YEAST), and three single-strain formulations of Bacillus amyloliquefaciens (SINGLE1), B. subtilis (SINGLE2) and B. licheniformis (SINGLE3). Alpha-diversity analyses showed that cecal microbiota of SINGLE1, SINGLE2, and YEAST had low diversity compared to the control diet with no feed additive (CON) at 21d. At the same age, weighted Unifrac distance measure showed significant differences between samples from SYNBIO and CON (P = 0.02). However, by analyzing principal coordinates analysis (PCoA) with unweighted Unifrac, there was no evidence of clustering between CON and probiotic treatments. By 42d, there were no differences in alpha or beta-diversity in the microbiota of probiotic treatments compared to CON. Similarly, taxonomic microbial profiling did not show major changes in cecal microbial taxa. In conclusion, not all probiotic-based formulations tested had a core benefit on the modulation of microbiota. However, based on the quantitative beta diversity results, SYNBIO greatly influenced the cecal microbial community structure attributable to transient variations in relative taxon abundance.


Assuntos
Ceco/microbiologia , Galinhas/microbiologia , Alimentos Formulados , Microbioma Gastrointestinal , Probióticos , Animais
14.
Int J Food Microbiol ; 326: 108641, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32371295

RESUMO

Thermotolerant Campylobacter is the leading bacterial cause of foodborne illness in humans worldwide. The objectives of this study were to estimate prevalence and to identify and characterize potential sources of thermotolerant Campylobacter contamination in broilers on farms and at the slaughterhouse; to evaluate the clonal relationship among thermotolerant Campylobacter isolates from different stages of the broiler meat supply chain, and to analyze the presence of virulence genes in different sources of thermotolerant Campylobacter. A total of 1210 samples were collected from three broiler meat supply chains in Santa Fe, Argentina. At the farms, the sampling collection included broilers one week prior to slaughter, wild-living birds, domestic dogs, wild rodents, farm workers' boots, litter, feed, drinking water, flies, and darkling beetles (Alphitobius diaperinus). At the slaughtering line, the samples taken were from the evisceration zone (broiler cecum, working surfaces, evisceration knives and workers' hands), from the chiller zone (surfaces and direct supply water) and from the packing zone (work surfaces, workers' hands and broiler carcasses). The samples taken along each supply chain were in the same batch. The isolates obtained were identified to the species level (C. jejuni and C. coli) by multiplex PCR and were analyzed using pulsed-field gel electrophoresis to compare different profiles according to the source. Finally, the presence of 11 virulence genes was examined (cadF, cdtA, cdtB, cdtC, ciaB, flaA, flhA, iam, wlaN, virB11, racR). From 254 isolates, 128 (50.4%) were Campylobacter jejuni and 126 (49.6%) Campylobacter coli. C. jejuni was the species most prevalent in farm and C. coli the species most prevalent at the slaughterhouse. We detected thermotolerant Campylobacter in samples of wild birds, darkling beetles, farm workers' boots, flies and litter. At the slaughterhouse, the prevalence varied along the process line. By analyzing PFGE results, C. jejuni showed 21 profiles with three predominant genotypes, while C. coli showed 14 profiles with four predominant genotypes. A high genotype diversity was found; however, relationships between isolates from different stages of the broiler meat chain, between broiler and potential sources of thermotolerant Campylobacter contamination and between strains in the farm and in the slaughterhouse were detected. Furthermore, there was evidence of cross-contamination at the slaughterhouse. FlaA, flhA genes were detected in all strains, and the third most prevalent virulence gene was cadF. Only those strains obtained from flies, wild-living birds and broiler carcass samples harbored 10 of 11 pathogenic genes. The prevalence of some pathogenic genes between C. jejuni and C. coli was different. This evidence should contribute the scientific basis to implement risk management measures in public health.


Assuntos
Campylobacter coli/genética , Campylobacter jejuni/genética , Doenças Transmitidas por Alimentos/microbiologia , Carne/microbiologia , Aves Domésticas/microbiologia , Matadouros/estatística & dados numéricos , Animais , Argentina , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Infecções por Campylobacter/microbiologia , Campylobacter coli/isolamento & purificação , Campylobacter coli/patogenicidade , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/patogenicidade , Proteínas de Transporte/genética , Ceco/microbiologia , Galinhas/microbiologia , Besouros/microbiologia , Dípteros/microbiologia , Cães , Água Potável/microbiologia , Eletroforese em Gel de Campo Pulsado , Flagelina/genética , Genótipo , Humanos , Indústria de Embalagem de Carne/estatística & dados numéricos , Proteínas de Membrana/genética , Prevalência , Roedores/microbiologia , Termotolerância , Virulência/genética
15.
J Food Sci ; 85(6): 1939-1947, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32468578

RESUMO

Mucin 2 (MUC2) is the skeleton of colonic mucus that comprises the physical intestinal barrier. Different dietary polysaccharides may affect colonic mucus at different extents. The effect of pectin on MUC2 production is contradictory. To investigate whether and how pectin affected hosts' colonic mucus, the amount of MUC2 in colon, the cecal, mucosal microbiota, and metabolites profiles were analyzed and compared with inulin. The results showed pectin stimulated the production of MUC2 at a similar level to inulin. Both interventions increased the abundance of cecal Lachnospira and Christensenellaceae_R-7_group, and enhanced the production of specific metabolites including soyasapogenol B 24-O-b-d-glucoside, lucyoside Q, trans-EKODE-(E)-Ib, and 1,26-dicaffeoylhexacosanediol. Additionally, pectin increased the relative abundance (RA) of cecal Lactobacillus, and induced less RA of potentially harmful bacteria such as Helicobacter in mucosal microbiota than inulin. In conclusion, we first reported that pectin and inulin stimulated the mucus formation at a similar level. Two genera of cecal bacteria and four metabolites may play an important role in enhancing the production of MUC2. Moreover, the MUC2 production may be unrelated to several traditional health-beneficial bacteria; pectin possibly performed as good as or better than the inulin in rats' gut.


Assuntos
Inulina/metabolismo , Muco/metabolismo , Pectinas/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Ceco/metabolismo , Ceco/microbiologia , Microbioma Gastrointestinal , Masculino , Mucina-2/metabolismo , Muco/microbiologia , Polissacarídeos/metabolismo , Ratos , Ratos Wistar
16.
Anim Sci J ; 91(1): e13387, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468650

RESUMO

This study was conducted to determine the effects of diet supplementation of laying hens with antimicrobial peptides (AMP) on egg production, egg quality and caecal microbiota. A total of 360 Hy-Line Brown laying hens (72 weeks old) were divided into three groups with four replicates of 30 birds each. The laying hens were fed with the basal diet (Control), the basal diet + 50 mg/kg AMP (group 1) and the basal diet + 100 mg/kg AMP (group 2). The experiment lasted for 45 d. Eggs were collected daily and caecal samples were collected at the end of the experiment. The results showed that AMP supplementation caused a significantly increased laying rate and decreased feed/egg ratio (p ï¼œ .05). Meanwhile, a distinctive difference in cecal microbiota was observed between AMP and control groups and the average values of microbial diversity and richness were lower in the AMP group than in the control group. At the phylum level, the relative abundance of Verrucomicrobia and Cyanobacteria were lower in the AMP group than in the control group. In conclusion, the results indicated that dietary supplementation with AMP can improve egg production and affect the cecal microbial community membership and structure of hens during late laying period.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/farmacologia , Ceco/microbiologia , Galinhas/microbiologia , Galinhas/fisiologia , Dieta/veterinária , Ovos , Qualidade dos Alimentos , Oviposição/efeitos dos fármacos , Animais , Suplementos Nutricionais , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos
17.
PLoS Comput Biol ; 16(4): e1007099, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32298268

RESUMO

The metabolic responses of bacteria to dynamic extracellular conditions drives not only the behavior of single species, but also entire communities of microbes. Over the last decade, genome-scale metabolic network reconstructions have assisted in our appreciation of important metabolic determinants of bacterial physiology. These network models have been a powerful force in understanding the metabolic capacity that species may utilize in order to succeed in an environment. Increasingly, an understanding of context-specific metabolism is critical for elucidating metabolic drivers of larger phenotypes and disease. However, previous approaches to use network models in concert with omics data to better characterize experimental systems have met challenges due to assumptions necessary by the various integration platforms or due to large input data requirements. With these challenges in mind, we developed RIPTiDe (Reaction Inclusion by Parsimony and Transcript Distribution) which uses both transcriptomic abundances and parsimony of overall flux to identify the most cost-effective usage of metabolism that also best reflects the cell's investments into transcription. Additionally, in biological samples where it is difficult to quantify specific growth conditions, it becomes critical to develop methods that require lower amounts of user intervention in order to generate accurate metabolic predictions. Utilizing a metabolic network reconstruction for the model organism Escherichia coli str. K-12 substr. MG1655 (iJO1366), we found that RIPTiDe correctly identifies context-specific metabolic pathway activity without supervision or knowledge of specific media conditions. We also assessed the application of RIPTiDe to in vivo metatranscriptomic data where E. coli was present at high abundances, and found that our approach also effectively predicts metabolic behaviors of host-associated bacteria. In the setting of human health, understanding metabolic changes within bacteria in environments where growth substrate availability is difficult to quantify can have large downstream impacts on our ability to elucidate molecular drivers of disease-associated dysbiosis across the microbiota. Our results indicate that RIPTiDe may have potential to provide understanding of context-specific metabolism of bacteria within complex communities.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Análise do Fluxo Metabólico , Redes e Vias Metabólicas , Transcriptoma , Algoritmos , Animais , Ceco/microbiologia , Biologia Computacional , Simulação por Computador , Disbiose , Microbioma Gastrointestinal , Perfilação da Expressão Gênica , Genoma Bacteriano , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos
18.
Arch Anim Nutr ; 74(4): 296-308, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32308036

RESUMO

Grape pomace (GP) is an abundant by-product from wine production and is rich in phenolic compounds, unsaturated fatty acids, dietary fibre and beneficial bacteria. In this study, weaned piglets were fed a basic diet supplemented with 5% GP for 4 weeks. Compared with those in the control (CON) group, it was found that the proportion of Lactobacillus delbrueckii, Olsenella umbonata and Selenomonas bovis in the caecum and the villus height and villus height/crypt depth ratio (VCR) of the jejunum were both significantly increased in the GP group (p < 0.05). Meanwhile, at the mRNA expression level, several proinflammatory cytokines (IL-1ß, IL-8, IL-6 and TNF-α) were significantly downregulated (p < 0.05) in piglet caecal tissue, and the short-chain fatty acid receptors (GPR41 and GPR43) were not significantly upregulated. In contrast, the levels of IgG was significantly increased (p < 0.05) in the sera of weaned piglets in the GP group. However, no difference in growth performance between the two groups of piglets was detected. These results show that GP had no adverse effects on the growth performance of piglets, but GP can promote the content of some beneficial bacteria in the caecum; this effect is conducive to improving the disease resistance potential of piglets.


Assuntos
Bactérias/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/microbiologia , Vitis/química , Actinobacteria/metabolismo , Ração Animal/análise , Animais , Ceco/efeitos dos fármacos , Ceco/microbiologia , DNA Bacteriano/análise , DNA Ribossômico/análise , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Frutas/química , Jejuno/efeitos dos fármacos , Jejuno/fisiologia , Lactobacillus delbrueckii/metabolismo , Masculino , Probióticos , Distribuição Aleatória , Selenomonas/metabolismo
19.
PLoS One ; 15(4): e0232088, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324793

RESUMO

Salmonella Enteritidis (SE) has been the most common Salmonella serotype associated with foodborne infections in the last several years. Dietary applications of yeast-based preparations in feed have shown to reduce Salmonella colonization in chickens augmenting SE control strategies. This study was conducted to evaluate the effects of a mannan-rich yeast cell wall-derived preparation (Actigen®) administered in feed at a rate of 400 g/ton on SE colonization in the cecum and internal organs of commercial layer chickens. Sixteen week-old layer pullets were orally challenged with a selected nalidixic acid resistant SE strain at a dose of 1.7×10^9 colony forming units (CFU) per bird. SE colonization was assessed by evaluating isolation rates from ovary and pooled liver/spleen samples as well as enumeration of SE in cecal pouches one week post-challenge. Recovery rates of SE from the ovaries of directly challenged birds receiving Actigen® were significantly lower (P <0.02) than those in directly challenged birds fed an unsupplemented control diet. Recovery rates of SE from pooled liver/spleen samples were not significantly different between Actigen®-treated pullets and controls (P = 0.22). Using direct plate count methods, cecal SE concentrations were 1 log10 lower (P <0.001) in challenged pullets in the Actigen®-supplemented group than in the challenged controls. The SE concentration distributions in the ceca were similar in groups testing positive and groups testing negative for SE in the ovaries and liver/spleens tissues. As a result, SE concentrations in the ceca could not be directly related to the occurrence or prevalence of SE in these tissues. In conclusion, Actigen® supplementation appears to decrease the prevalence of SE in ovarian tissue and concentrations of SE in cecal contents and may be useful as a tool for reducing the risk of eggshell contamination and transovarian transmission of SE in eggs.


Assuntos
Ceco/microbiologia , Mananas/farmacologia , Ovário/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Salmonella enteritidis/efeitos dos fármacos , Ração Animal , Animais , Ceco/efeitos dos fármacos , Parede Celular/metabolismo , Galinhas , Suplementos Nutricionais , Feminino , Ovário/microbiologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Prevalência , Salmonelose Animal/epidemiologia , Salmonelose Animal/prevenção & controle
20.
Br J Nutr ; 124(6): 567-576, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32312334

RESUMO

Dietary fibre fermentation in humans and monogastric animals is considered to occur in the hindgut, but it may also occur in the lower small intestine. This study aimed to compare ileal and hindgut fermentation in the growing pig fed a human-type diet using a combined in vivo/in vitro methodology. Five pigs (23 (sd 1·6) kg body weight) were fed a human-type diet. On day 15, pigs were euthanised. Digesta from terminal jejunum and terminal ileum were collected as substrates for fermentation. Ileal and caecal digesta were collected for preparing microbial inocula. Terminal jejunal digesta were fermented in vitro with a pooled ileal digesta inoculum for 2 h, whereas terminal ileal digesta were fermented in vitro with a pooled caecal digesta inoculum for 24 h. The ileal organic matter fermentability (28 %) was not different from hindgut fermentation (35 %). However, the organic matter fermented was 66 % greater for ileal fermentation than hindgut fermentation (P = 0·04). Total numbers of bacteria in ileal and caecal digesta did not differ (P = 0·09). Differences (P < 0·05) were observed in the taxonomic composition. For instance, ileal digesta contained 32-fold greater number of the genus Enterococcus, whereas caecal digesta had a 227-fold greater number of the genus Ruminococcus. Acetate synthesis and iso-valerate synthesis were greater (P < 0·05) for ileal fermentation than hindgut fermentation, but propionate, butyrate and valerate synthesis was lower. SCFA were absorbed in the gastrointestinal tract location where they were synthesised. In conclusion, a quantitatively important degree of fermentation occurs in the ileum of the growing pig fed a human-type diet.


Assuntos
Ceco/metabolismo , Dieta , Fermentação , Íleo/metabolismo , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/metabolismo , Ceco/microbiologia , Fibras na Dieta/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Humanos , Íleo/microbiologia , Suínos
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