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1.
J Med Microbiol ; 69(2): 290-297, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32004137

RESUMO

Introduction. Staphylococcus aureus is a recognised cause of foodborne intoxication and antibiotic-associated diarrhoea (AAD), which are both mediated by staphylococcal enterotoxins. However, unlike foodborne intoxication, AAD appears to require infection of the host. While S. aureus intoxication is widely studied, little is known about S. aureus pathogenesis in the context of gastrointestinal infection.Aim. To develop a mouse model of S. aureus gastrointestinal infection.Methodology. An established AAD mouse model was adapted for S. aureus infection, and damage observed via histopathological analysis and immunostaining of intestinal tissues.Results. Various strains colonised the mouse model, and analysis showed that although clinical signs of disease were not seen, S. aureus infection induced damage in the small intestine, disrupting host structures essential for epithelial integrity. Studies using a staphylococcal enterotoxin B mutant showed that this toxin may contribute to damage during gastrointestinal infection.Conclusion. This work presents a new mouse model of S. aureus gastrointestinal infection, while also providing insight into the pathogenesis of S. aureus in the gut.


Assuntos
Intestino Delgado/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Animais , Modelos Animais de Doenças , Enterotoxinas/genética , Enterotoxinas/metabolismo , Enterotoxinas/toxicidade , Fezes/microbiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Staphylococcus aureus/genética
2.
Int. microbiol ; 22(4): 429-435, dic. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-185061

RESUMO

Studies of the digestive microbiota of ruminant animals most often focus on the bacterial diversity in the rumen or the feces of the animals, but little is known about the diversity and functions of their distal intestine. Here, the bacterial microbiota of the distal intestinal tract of two goats and two camels was investigated by metagenomics techniques. The bacterial taxonomic diversity and carbohydrate-active enzyme profile were estimated for samples taken from the small intestine, the large intestine, and the rectum of each animal. The bacterial diversity and abundance in the small intestine were lower than in the rectal and large intestinal samples. Analysis of the carbohydrate-active enzyme profiles at each site revealed a comparatively low abundance of enzymes targeting xylan and cellulose in all animals examined, similar to what has been reported earlier for sheep and therefore suggesting that plant cell wall digestion probably takes place elsewhere, such as in the rumen


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Assuntos
Animais , Camelus , Metagenômica/métodos , Microbioma Gastrointestinal , Ativação Enzimática/genética , Cabras , Trato Gastrointestinal/microbiologia , Intestino Delgado/microbiologia , Intestino Grosso/microbiologia , Estômago de Ruminante/enzimologia , Estômago de Ruminante/microbiologia , Ruminantes/microbiologia
3.
Altern Ther Health Med ; 25(5): 30-38, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31550680

RESUMO

Context: Small intestinal bacterial overgrowth (SIBO) has gained popularity on the internet in addition to certain clinical and research circles. This interest has expanded awareness of important new dietary, nutraceutical, and pharmaceutical treatments in addition to laboratory evaluation assessment options. Concomitantly, there appears a loss of parsimony regarding how to use these tools resulting in an untenable degree of testing and treatment for this condition. Objectives: A balanced review of the data regarding SIBO testing, treatment, and management with the goal of establishing non-biased best practices. Design: Non-systematic review. Results: The results for the review fall into two categories. Ineffective Action: Treat only SIBO labs; Treat for SIBO if no symptoms are exhibited; Recommending eating or avoiding foods because they might be good or bad for SIBO; Recommending treatments that are non-validated. Effective Action: Use SIBO breath results, in addition to history and current symptoms, to determine the best treatment; Find foods that work for patients based on dietary elimination and reintroduction; Apply validated treatment for SIBO and IBS in a logical 'step-up' like treatment approach. Conclusions: Testing and treating for SIBO can offer patients clinically significant relief. However, these tests and treatments must be applied with circumspection to prevent over-testing, over-treatment, squandering resources, or creating a fear around certain foods.


Assuntos
Infecções Bacterianas/diagnóstico , Enteropatias/microbiologia , Intestino Delgado/microbiologia , Síndrome do Intestino Irritável/microbiologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Testes Respiratórios , Dietoterapia , Fármacos Gastrointestinais , Humanos , Enteropatias/diagnóstico , Enteropatias/terapia
4.
Lett Appl Microbiol ; 69(5): 325-332, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454425

RESUMO

The aim of the research was to develop a galenical formulation for the combination of the three probiotic strains Lactobacillus gasseri PA 16/8, Bifidobacterium longum SP 07/3 and Bifidobacterium bifidum MF 20/5 that would lead to the presence of a high amount of viable cells in the small intestine, the presumed site of action of these strains. This was tested in a validated, dynamic in vitro model of the stomach and small intestine (TIM-1), simulating human adults after intake of a meal. Experiments were performed both in the gastric compartment of the model, as well as in the complete system (stomach + small intestine). Survival of the strains in an unformulated probiotic powder after transit through the gastric compartment was 5·3% for the bifidobacteria and 1% for L. gasseri. After transit through the complete gastrointestinal tract, this dropped to 2% for bifidobacteria and 0·1% for Lactobacillus. After several rounds of optimization, an enteric-coated tablet was developed that increased the delivery of viable cells reaching the small intestine to 72% (gastric survival) for bifidobacteria, and 53% (gastric) for L. gasseri. Also survival in the small intestine increased by about an order of magnitude. The final galenical formulation was tested in two applications: adults and elderly, both of which have their own physiological parameters. These experiments corroborated the results obtained in the development phase of the project. In conclusion, the developed enteric coating led to a 20- to 40-fold increase in the delivery of viable cells to the small intestine. SIGNIFICANCE AND IMPACT OF THE STUDY: Predictive GI in vitro models are very helpful and reliable tools for the development of new galenical formula containing probiotics, and in the current example helped to deliver >10-fold higher numbers of viable cells to the small intestine, presumably leading to improved functionality of the strains.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Intestino Delgado/microbiologia , Lactobacillus/crescimento & desenvolvimento , Probióticos/química , Estômago/microbiologia , Adulto , Idoso , Composição de Medicamentos , Humanos , Viabilidade Microbiana , Comprimidos/química
5.
Food Funct ; 10(9): 5361-5373, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31393487

RESUMO

The early postnatal stage is a critical period for suckling animals in developing intestinal function and stabilizing gut microbiota. Lactoferrin (LF) plays a critical role in promoting gut development and regulating gut microbiota. This study investigates the impact of early-life lactoferrin (LF) intervention on the growth performance, small intestinal function and gut microbiota in suckling piglets. Sixty suckling piglets (1.51 ± 0.05 kg) obtained from six sows (10 piglets per litter) were assigned to a control (CON) group and an LF group in each litter, which were sow-fed. Piglets in the LF group were orally administered 8-12 mL LF solution (0.5 g per kg body weight per day) for a week, and piglets in the CON group were orally administered the same dose of physiological saline. Six piglets (n = 6) from each group were euthanized on days 8 and 21. The early-life LF intervention increased growth performance, with higher villi height of the jejunum and greater disaccharidase activity of the jejunum and ileum (P < 0.05). Diarrhoea incidence decreased in the LF group from day 1 to day 7 (P < 0.05). Urinary lactulose-mannitol ratios decreased in the LF group, whereas the gene and protein expressions of jejunal occludin increased in the LF group on day 8 and day 21, and higher gene and protein levels of ileal occludin were observed on day 8 (P < 0.05). Additionally, the LF piglets had lower concentrations of IL-1ß and TNF-α, and higher concentration of IL-10 in the jejunum (P < 0.05). For the ileum, higher concentration of IL-10 and lower concentration of TNF-α were observed in the LF group (P < 0.05). LF piglets had a greater abundance of Lactobacillus and lower abundance of Veillonella and Escherichia-Shigella in the jejunum on day 8 (P < 0.05). In the ileum, the abundance of Actinobacillus was decreased in the LF piglets on day 8 and day 21 (P < 0.05). The early-life LF intervention enhanced the growth performance and decreased diarrhoea incidence in the suckling piglets by promoting the development of intestinal function and changing the microbiota in the small intestine.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Intestino Delgado/microbiologia , Lactoferrina/administração & dosagem , Suínos/crescimento & desenvolvimento , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bovinos , Feminino , Interleucina-10/genética , Interleucina-10/metabolismo , Intestino Delgado/crescimento & desenvolvimento , Intestino Delgado/fisiologia , Masculino , Suínos/microbiologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
6.
Rev Gastroenterol Peru ; 39(2): 111-115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333225

RESUMO

OBJECTIVES: Small intestinal bacterial overgrowth (SIBO) is challenging to treat and diagnose and is associated with diagnosis of irritable bowel syndrome (IBS). Although no FDA-approved medications exist for treatment of SIBO, rifaximin has recently received approval to treat diarrhea-predominant IBS and patients with methane-positive SIBO breath tests. The aim of this study is to evaluate patient response to rifaximin for SIBO based on breath test results. MATERIALS AND METHODS: All patients underwent breath testing to evaluate for SIBO during a 42-month period. Patients were defined as having a positive glucose breath test for SIBO based on an increase of ≥ 20 ppm of hydrogen and/or ≥ 10 ppm of methane 90 minutes after ingesting glucose. Patient demographic and symptom data, antibiotic treatment regimens, symptomatic response to therapy, and repeat treatments were recorded. Institutional review board approval was obtained. RESULTS: A total of 53 of 443 patients had positive breath testing for SIBO. Response rates to rifaximin (550 mg three times daily for 14 days) were 47.4% for hydrogen positivity alone and 80% for both hydrogen and methane positivity. CONCLUSIONS: Rifaximin was the most commonly prescribed antibiotic regimen for SIBO therapy. Patients with hydrogen or hydrogen and methane positive breath tests responded well to rifaximin therapy. For patients with hydrogen-positive SIBO, rifaximin may prove a highly effective therapy in providing symptom relief from the effects of SIBO.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Intestino Delgado/microbiologia , Rifaximina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/metabolismo , Testes Respiratórios , Feminino , Humanos , Hidrogênio/análise , Hidrogênio/metabolismo , Masculino , Metano/análise , Metano/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
8.
Curr Gastroenterol Rep ; 21(8): 38, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31289936

RESUMO

PURPOSE OF REVIEW: This review discusses the prevalence of malnutrition in cirrhosis, metabolic functions of the liver and alterations in cirrhosis, malnutrition screening tools, and common macronutrient and micronutrient deficiencies encountered in individuals with chronic liver disease and their impact on morbidity and mortality. RECENT FINDINGS: Several meta-analyses and international society guidelines recommend malnutrition screening and nutrition interventions to improve outcomes in all patients with chronic liver disease given their high risk of malnutrition which is often under recognized. Malnutrition is common in individuals with chronic liver disease and has a significant impact on patient outcomes. Thus, it is critical that validated malnutrition screening tools are used routinely in this patient population in order to identify high-risk patients and implement nutrition and exercise interventions early.


Assuntos
Cirrose Hepática/complicações , Desnutrição/etiologia , Composição Corporal/fisiologia , Diarreia/etiologia , Motilidade Gastrointestinal/fisiologia , Humanos , Intestino Delgado/microbiologia , Fígado/metabolismo , Cirrose Hepática/dietoterapia , Cirrose Hepática/metabolismo , Desnutrição/diagnóstico , Desnutrição/dietoterapia , Desnutrição/metabolismo , Doenças Metabólicas/etiologia , Avaliação Nutricional , Apoio Nutricional/métodos
9.
Poult Sci ; 98(10): 5074-5088, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31180129

RESUMO

Clostridium perfringens is a Gram-positive opportunistic pathogen that is the principal etiological agent of necrotic enteritis (NE) in poultry. The ability of C. perfringens to incite NE depends upon its ability to penetrate the protective mucus barrier within the small intestine, which is largely composed of heavily glycosylated proteins called mucins. Mucins are decorated by N- and O-linked glycans that serve both as a formidable gel-like barrier against invading pathogens and as a rich carbon source for mucolytic bacteria. The composition of avian O-linked glycans is markedly different from mucins in other vertebrates, being enriched in sulfated monosaccharides and N-acetyl-d-neuraminic acid (Neu5Ac, sialic acid). These modifications increase the overall negative charge of mucins and are believed to impede colonization by enteric pathogens. The mechanism by which C. perfringens penetrates the poultry intestinal mucus layer during NE is still unknown. However, the CAZome (i.e., the total collection of proteins encoded within a genome active on carbohydrates) of C. perfringens strain CP1 encodes several putative and known enzymes with activities consistent with the modification of mucin. To further investigate this relationship, O-glycans from Gallus gallus domesticus mucus were extracted from the small intestine and characterized using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Chicken mucin monosaccharides included l-fucose (Fuc), d-mannose (Man), d-galactose (Gal), N-acetyl-d-galactosamine (GalNAc), N-acetyl-d-glucosamine (GlcNAc), and Neu5Ac (sialic acid). Using these monosaccharides as sole carbon sources, we showed that C. perfringens CP1 grew on Neu5Ac, Man, Gal, and GlcNAc but not on Fuc and GalNAc. We also demonstrated C. perfringens grew on different native-state preparations of intestinal mucins and mucus including porcine mucins, chicken mucus, and chicken mucins. Finally, anaerobic incubation of chicken mucin O-glycans with C. perfringens and subsequent analysis of the glycans revealed that there was preferential removal of Neu5Ac. These observations are discussed in the context of the predicted metabolic potential of C. perfringens CP1 and the mucolytic enzymes encoded within its CAZome.


Assuntos
Galinhas/microbiologia , Clostridium perfringens/fisiologia , Mucinas/química , Polissacarídeos/química , Animais , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia
10.
Microb Pathog ; 135: 103567, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31163250

RESUMO

Clostridium perfringens (C. perfringens), a Gram-positive bacterium, is one of the main causing piglet diarrhea, which leads serious economic loss in the world swine industries. Generally, the innate immune response plays a critical role in host defense against pathogen invasion. TLR4, a member of the TLR (Toll-like receptor) family, has been considered to implicate in the host immune responses and induce secretion of inflammatory cytokines during bacterial infection. However, little is clear about the effects of TLR4 and key signaling genes in the process of piglet inflammatory and immune responses after C. perfringens infection. This study aims to explore the effect of C. perfringens type C infection on the key mRNAs of TLR4/MyD88/NF-κB signaling pathways during the process of piglet diarrhea. In this study, the expressions of TLR4 and other key mRNAs in the TLR4/MyD88/NF-κB signaling pathways were quantified in piglet ileum and jejunum tissues among IR (intestinal resistance), IS (intestinal susceptibility) and IC (intestinal control) groups by qPCR and Western blot methods, the concentrations of pro-inflammatory cytokines in intestinal tissues and serum immunoglobulins were also tested by ELISA kits. Results showed that compared to IC group, expressions of ileum TLR4 and TNF-α was significantly increased in the IS and IR groups, specially TBK1 gene; the expressions of ileum TLR2, TRAF6, MyD88 and IL-8 mRNAs was significantly up-regulated in the IS group, the expressions of TLR9, NF-κB, IL-6, IFN-γ and MAPK1 genes were not significant differences among the IR, IS and IC groups. Meanwhile, the protein levels of TLR4, HMGB1 and NF-κB were higher in the IS and IR groups. The levels of jejunum IFN-γ and IL-6, ileum IL-6 and IL-12 were risen in the IR group. Serum immunoglobulin IgA and IgG in the IR and IS groups reached a peak on the 72 h and 48 h post infection, respectively. These findings suggest that C. perfringens type C infection induces host immune responses involving in the TLR4/MyD88/NF-κB signaling pathways in ileum than in jejunum, which may provide valuable information for innate immune mechanisms involved in regulation of piglet diarrhea caused by C. perfringens type C infection.


Assuntos
Infecções por Clostridium/imunologia , Clostridium perfringens/patogenicidade , Intestino Delgado/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Animais , Infecções por Clostridium/microbiologia , Citocinas/genética , Citocinas/metabolismo , Diarreia/imunologia , Diarreia/microbiologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Imunidade Inata , Imunoglobulinas/sangue , Intestino Delgado/microbiologia , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , Suínos , Receptor 4 Toll-Like/genética , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Nutrients ; 11(7)2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31252646

RESUMO

Citrus flavanones, with hesperidin and naringin as the most abundant representatives, have various beneficial effects, including anti-oxidative and anti-inflammatory activities. Evidence also indicates that they may impact the intestinal microbiome and are metabolized by the microbiota as well, thereby affecting their bioavailability. In this review, we provide an overview on the current evidence on the intestinal fate of hesperidin and naringin, their interaction with the gut microbiota, and their effects on intestinal barrier function and intestinal inflammation. These topics will be discussed as they may contribute to gastrointestinal health in various diseases. Evidence shows that hesperidin and naringin are metabolized by intestinal bacteria, mainly in the (proximal) colon, resulting in the formation of their aglycones hesperetin and naringenin and various smaller phenolics. Studies have also shown that citrus flavanones and their metabolites are able to influence the microbiota composition and activity and exert beneficial effects on intestinal barrier function and gastrointestinal inflammation. Although the exact underlying mechanisms of action are not completely clear and more research in human subjects is needed, evidence so far suggests that citrus flavanones as well as their metabolites have the potential to contribute to improved gastrointestinal function and health.


Assuntos
Bactérias/metabolismo , Citrus/metabolismo , Colo/metabolismo , Flavanonas/metabolismo , Frutas/metabolismo , Gastroenterite/prevenção & controle , Microbioma Gastrointestinal , Hesperidina/metabolismo , Absorção Intestinal , Intestino Delgado/metabolismo , Animais , Bactérias/efeitos dos fármacos , Disponibilidade Biológica , Colo/efeitos dos fármacos , Colo/microbiologia , Flavanonas/administração & dosagem , Gastroenterite/metabolismo , Gastroenterite/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Hesperidina/administração & dosagem , Humanos , Absorção Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/microbiologia
12.
Trop Anim Health Prod ; 51(8): 2187-2192, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31119514

RESUMO

In this study, 600 1-day-old Japanese quail chicks (Coturnix coturnix japonica) were used to investigate the effects of bacteriocin and organic acids on performance and intestinal histomorphology and microbiology. Chicks were allocated to 6 groups, i.e., control, Bac150 (150 mg/kg bacteriocin), Bac300 (300 mg/kg bacteriocin), OA (3 g/kg organic acid blend), Bac150+OA (150 mg/kg bacteriocin + 3 g/kg organic acid blend), and Bac300+OA (300 mg/kg bacteriocin + 3 g/kg organic acid blend) group. The trial lasted 35 days. At the end of the trial, a statistical increase was not observed in the performance parameters of chicks with feed additives. However, 300 mg/kg bacteriocin + 3 g/kg organic acid supplementation given together has been found to have more positive effects on intestinal microbiology and histomorphology (P < 0.05). Consequently, it is understood that the use of these feed additives together will achieve better results.


Assuntos
Ração Animal , Bacteriocinas , Coturnix/crescimento & desenvolvimento , Animais , Coturnix/anatomia & histologia , Coturnix/microbiologia , Suplementos Nutricionais , Feminino , Intestino Delgado/anatomia & histologia , Intestino Delgado/microbiologia , Masculino , Distribuição Aleatória
13.
Nat Commun ; 10(1): 2012, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043597

RESUMO

Small intestinal bacterial overgrowth (SIBO) has been implicated in symptoms associated with functional gastrointestinal disorders (FGIDs), though mechanisms remain poorly defined and treatment involves non-specific antibiotics. Here we show that SIBO based on duodenal aspirate culture reflects an overgrowth of anaerobes, does not correspond with patient symptoms, and may be a result of dietary preferences. Small intestinal microbial composition, on the other hand, is significantly altered in symptomatic patients and does not correspond with aspirate culture results. In a pilot interventional study we found that switching from a high fiber diet to a low fiber, high simple sugar diet triggered FGID-related symptoms and decreased small intestinal microbial diversity while increasing small intestinal permeability. Our findings demonstrate that characterizing small intestinal microbiomes in patients with gastrointestinal symptoms may allow a more targeted antibacterial or a diet-based approach to treatment.


Assuntos
Disbiose/microbiologia , Gastroenteropatias/microbiologia , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/metabolismo , Intestino Delgado/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos , DNA Bacteriano/isolamento & purificação , Fibras na Dieta/administração & dosagem , Açúcares da Dieta/efeitos adversos , Disbiose/dietoterapia , Disbiose/tratamento farmacológico , Disbiose/fisiopatologia , Feminino , Gastroenteropatias/dietoterapia , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/fisiopatologia , Voluntários Saudáveis , Humanos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/fisiopatologia , Intestino Delgado/metabolismo , Intestino Delgado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Permeabilidade , Projetos Piloto , Adulto Jovem
14.
mBio ; 10(3)2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138751

RESUMO

Oral infection of C57BL/6J mice with Toxoplasma gondii results in a marked bacterial dysbiosis and the development of severe pathology in the distal small intestine that is dependent on CD4+ T cells and interferon gamma (IFN-γ). This dysbiosis and bacterial translocation contribute to the development of ileal pathology, but the factors that support the bloom of bacterial pathobionts are unclear. The use of microbial community profiling and shotgun metagenomics revealed that Toxoplasma infection induces a dysbiosis dominated by Enterobacteriaceae and an increased potential for nitrate respiration. In vivo experiments using bacterial metabolic mutants revealed that during this infection, host-derived nitrate supports the expansion of Enterobacteriaceae in the ileum via nitrate respiration. Additional experiments with infected mice indicate that the IFN-γ/STAT1/iNOS axis, while essential for parasite control, also supplies a pool of nitrate that serves as a source for anaerobic respiration and supports overgrowth of Enterobacteriaceae Together, these data reveal a trade-off in intestinal immunity after oral infection of C57BL/6J mice with T. gondii, in which inducible nitric oxide synthase (iNOS) is required for parasite control, while this host enzyme is responsible for specific modification of the composition of the microbiome that contributes to pathology.IMPORTANCE Toxoplasma gondii is a protozoan parasite and a leading cause of foodborne illness. Infection is initiated when the parasite invades the intestinal epithelium, and in many host species, this leads to intense inflammation and a dramatic disruption of the normal microbial ecosystem that resides in the healthy gut (the so-called microbiome). One characteristic change in the microbiome during infection with Toxoplasma-as well as numerous other pathogens-is the overgrowth of Escherichia coli or similar bacteria and a breakdown of commensal containment leading to seeding of peripheral organs with gut bacteria and subsequent sepsis. Our findings provide one clear explanation for how this process is regulated, thereby improving our understanding of the relationship between parasite infection, inflammation, and disease. Furthermore, our results could serve as the basis for the development of novel therapeutics to reduce the potential for harmful bacteria to bloom in the gut during infection.


Assuntos
Disbiose/imunologia , Microbioma Gastrointestinal , Intestino Delgado/imunologia , Intestino Delgado/patologia , Ativação de Macrófagos , Nitratos/metabolismo , Toxoplasmose Animal/imunologia , Animais , Citocinas/análise , Enterobacteriaceae/classificação , Feminino , Inflamação , Interferon gama/imunologia , Intestino Delgado/microbiologia , Intestino Delgado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/imunologia , Toxoplasma/patogenicidade , Toxoplasmose Animal/microbiologia
15.
Gastroenterology ; 157(3): 637-646.e4, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31095949

RESUMO

BACKGROUND & AIMS: Enteropathy and small-intestinal ulcers are common adverse effects of nonsteroidal anti-inflammatory drugs such as acetylsalicylic acid (ASA). Safe, cytoprotective strategies are needed to reduce this risk. Specific bifidobacteria might have cytoprotective activities, but little is known about these effects in humans. We used serial video capsule endoscopy (VCE) to assess the efficacy of a specific Bifidobacterium strain in healthy volunteers exposed to ASA. METHODS: We performed a single-site, double-blind, parallel-group, proof-of-concept analysis of 75 heathy volunteers given ASA (300 mg) daily for 6 weeks, from July 31 through October 24, 2017. The participants were randomly assigned (1:1) to groups given oral capsules of Bifidobacterium breve (Bif195) (≥5 × 1010 colony-forming units) or placebo daily for 8 weeks. Small-intestinal damage was analyzed by serial VCE at 6 visits. The area under the curve (AUC) for intestinal damage (Lewis score) and the AUC value for ulcers were the primary and first-ranked secondary end points of the trial, respectively. RESULTS: Efficacy data were obtained from 35 participants given Bif195 and 31 given placebo. The AUC for Lewis score was significantly lower in the Bif195 group (3040 ± 1340 arbitrary units) than the placebo group (4351 ± 3195) (P = .0376). The AUC for ulcer number was significantly lower in the Bif195 group (50.4 ± 53.1 arbitrary units) than in the placebo group (75.2 ± 85.3 arbitrary units) (P = .0258). Twelve adverse events were reported from the Bif195 group and 20 from the placebo group. None of the events was determined to be related to Bif195 intake. CONCLUSIONS: In a randomized, double-blind trial of healthy volunteers, we found oral Bif195 to safely reduce the risk of small-intestinal enteropathy caused by ASA. ClinicalTrials.gov no: NCT03228589.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Bifidobacterium breve/crescimento & desenvolvimento , Microbioma Gastrointestinal , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/microbiologia , Probióticos/administração & dosagem , Úlcera/prevenção & controle , Adolescente , Adulto , Endoscopia por Cápsula , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Intestino Delgado/patologia , Irlanda , Masculino , Probióticos/efeitos adversos , Fatores de Tempo , Úlcera/induzido quimicamente , Úlcera/microbiologia , Úlcera/patologia , Adulto Jovem
16.
Wiad Lek ; 72(4): 645-649, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31055549

RESUMO

OBJECTIVE: Introduction: Small intestinal bacterial overgrowth may cause the hyperlipidemia appearance by enterohepatic circulation disturbance which evolves on the background of the early bile acids deconjugation with further endotoxin production and oxidative stress in the liver with hyperproduction of cholesterol and atherogenic lipoproteins. The aim: the determination of prevalence and features of SIBO in a series of patients with hyperlipidemia and in control subjects. PATIENTS AND METHODS: Materials and methods: Nineteen patients with hyperlipidemia and ten control subjects were studied. Small intestinal bacterial overgrowth was assessed by a lactulose breath test. Such biochemical markers as CRP, ALT, AST, GGTP, apolipoprotein B, bilirubin, cholesterol and lipid profile were determined. Except the routine interpretation of lactulose breath test, which contains the SIBO detection, small intestinal transit time and hydrogen level evaluation with next comparison between groups of patients was realized. RESULTS: Results: Small intestinal bacterial overgrowth was present in 78.9% of patients with hyperlipidemia and 40% in control subjects. The maximal dose of H2 was particularly higher in patients with hyperlipidemia in comparison with control group (94,7±13,69 vs. 36,13±5,4). There was a strong correlation between AST level and SIBO existence in both groups (r=1). Positive connection between LDL, TG, VLDL and the dose of exhaled hydrogen on 120 minute (r=0.6, r= 0.62, r=0.7 respectively) and strong negative correlation between HDL and 120 minute dose (r=-0.74) in main group was marked. CONCLUSION: Conclusions: Patients with hyperlipidemia have a higher prevalence of small intestinal bacterial overgrowth and there is a relationship between H2 rate and LDL, TG, VLDL.


Assuntos
Infecções Bacterianas/complicações , Disbiose/complicações , Hiperlipidemias/microbiologia , Intestino Delgado/microbiologia , Testes Respiratórios , Estudos de Casos e Controles , Humanos , Lactulose
17.
PLoS One ; 14(5): e0215351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31095575

RESUMO

Short bowel syndrome (SBS) presents an increasing problem in pediatrics. SBS often results from surgical resection of necrotic bowel following necrotizing enterocolitis or treatment of anatomic gastrointestinal defects. SBS is associated with significant morbidity and mortality, and creates substantial burdens for patients, families, and the health system. Recent reports have demonstrated that the fecal microbiome of children with SBS is significantly different from healthy control and severe intestinal microbial imbalances is associated with poor growth. We hypothesized that children with SBS and adverse clinical features such as PN dependent, shorter bowel length and lack of ileocecal valve would demonstrate more gut dysbiosis compare with the SBS non-PN dependent. An improved understanding of SBS pathogenesis would enhance management and potentially suggest new interventions. We studied microbial communities of SBS and control non-SBS patients from the jejunum, obtained endoscopically or by ostomy aspiration, and stool. We enrolled SBS patients who did and did not require parenteral nutrition (PN), as a surrogate marker for the seriousness of their disease. We studied the microbiota using high-throughput DNA sequencing of 16S rRNA genes and statistical analyses. We found that microbial diversity was significantly greater in jejunal aspirate than in stool samples in SBS patients, unlike non-SBS patients; that SBS patients receiving enteral feeds had greater diversity, and that SBS patients on PN and enteral feeds had lower differences in diversity in jejunal vs. stool samples. We found a trend toward increased diversity in patients with an intact ileocecal valve, and found that certain taxa were more abundant in the certain sample types, and in SBS patients vs. non-SBS patients. SBS patients have lower microbial diversity, especially patients with more severe disease, patients requiring PN, and those lacking an ileocecal valve. SBS patients, particularly those with more complex characteristics, exhibit differences in their intestinal microbiota. Particular individual taxa were over- and under-represented in patients with more unfavorable disease. While diminished diversity and alterations in microbiota composition are likely consequences of SBS, future efforts aimed at increasing microbial diversity and interventions targeting specific microbiota characteristics might constitute a testable approach to ameliorate some clinical SBS clinical consequences.


Assuntos
Bactérias/classificação , Fezes/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Intestino Delgado/microbiologia , Síndrome do Intestino Curto/microbiologia , Bactérias/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Prospectivos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos
18.
Wiad Lek ; 72(3): 350-356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050979

RESUMO

OBJECTIVE: Introduction: In recent years, NAFLD is considered as the key of the so-called metabolic inflammation, in which the intestinal microbiota plays an important role. The aim: To determine the effect of small intestine bacterial overgrowth on the liver structural and functional parameters in children with obesity and overweight. PATIENTS AND METHODS: Materials and methods: The object of the study was 89 children with obesity/overweight. Depending on the presence of SIBO based on the results of the hydrogen breath test with glucose, the patients were divided into 2 groups: first (I) consisted of 31 children with SIBO, the second (II) included 58 children without SIBO. All the patients under study performed a general blood analysis and a biochemical blood test, immuno-enzyme test method with insulin level determination HOMA index calculation. For diagnostics of the liver steatosis, transient elastography with the CAP (controlled attenuation parameter) function was carried out using FibroScan® 502 touch (Echosens, Paris, France). RESULTS: Results: According to fibroscan data, the presence of SIBO in obese children can lead to raise of CAP level; liver steatosis was diagnosed in 22 patients (70.9%) of the 1st group and 24 patients (41.4%) of the 2 group (p<0,05). We found significant differences in the the ratio of neutrophils and lymphocytes (NLR) (p <0.05). The average glucose level and HOMA index were significantly higher in SIBO group (p<0,05). The analysis of risk factors of SIBO showed that metabolic syndrome and NAFLD as the risk factors for SIBO development (p<0,05). CONCLUSION: Conclusions: SIBO has an effect on the structural and functional characteristics of the liver resulting in higher insulin and glucose level, higher NLR level and greater prevalence of NAFLD.


Assuntos
Infecções Bacterianas , Hepatopatia Gordurosa não Alcoólica , Infecções Bacterianas/complicações , Testes Respiratórios , Criança , Humanos , Intestino Delgado/microbiologia , Obesidade , Sobrepeso/complicações
19.
Front Med ; 13(4): 451-460, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31020543

RESUMO

Understanding the effect of immunosuppressive agents on intestinal microbiota is important to reduce the mortality and morbidity from orthotopic liver transplantation (OLT). We investigated the relationship between the commonly used immunosuppressive agent cyclosporine A (CSA) and the intestinal microbial variation in an OLT model. The rat samples were divided as follows: (1) N group (normal control); (2) I group (isograft LT, Brown Norway [BN] rat to BN); (3) R group (allograft LT, Lewis to BN rat); and (4) CSA group (R group treated with CSA). The intestinal microbiota was assayed by denaturing gradient gel electrophoresis profiles and by using real-time polymerase chain reaction. The liver histopathology and the alanine/aspartate aminotransferase ratio after LT were both ameliorated by CSA. In the CSA group, the numbers of rDNA gene copies of Clostridium cluster I, Clostridium cluster XIV, and Enterobacteriaceae decreased, whereas those of Faecalibacterium prausnitzii increased compared with the R group. Cluster analysis indicated that the samples from the N, I, and CSA groups were clustered, whereas the other clusters contained the samples from the R group. Hence, CSA ameliorates hepatic graft injury and partially restores gut microbiota following LT, and these may benefit hepatic graft rejection.


Assuntos
Ciclosporina/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Rejeição de Enxerto/prevenção & controle , Imunossupressores/administração & dosagem , Intestino Delgado/microbiologia , Transplante de Fígado/efeitos adversos , Animais , Análise por Conglomerados , Fígado/patologia , Testes de Função Hepática , Masculino , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew
20.
Infect Immun ; 87(6)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30962403

RESUMO

The genital tract pathogen Chlamydia trachomatis is frequently detected in the gastrointestinal tract, but the host immunity that regulates chlamydial colonization in the gut remains unclear. In a Chlamydia muridarum-C57 mouse model, chlamydial organisms are cleared from the genital tract in ∼4 weeks, but the genital organisms can spread to the gastrointestinal tract. We found that the gastrointestinal chlamydial organisms were cleared from the small intestine by day 28, paralleling their infection course in the genital tract, but persisted in the large intestine for long periods. Mice deficient in α/ß T cells or CD4+ T cells but not CD8+ T cells showed chlamydial persistence in the small intestine, indicating a critical role for CD4+ T cells in clearing Chlamydia from the small intestine. The CD4+ T cell-dependent clearance is likely mediated by gamma interferon (IFN-γ), since mice deficient in IFN-γ but not interleukin 22 (IL-22) signaling pathways rescued chlamydial colonization in the small intestine. Furthermore, exogenous IFN-γ was sufficient for clearing Chlamydia from the small intestine but not the large intestine. Mice deficient in developing Chlamydia-specific Th1 immunity showed chlamydial persistence in the small intestine. Finally, IFN-γ-producing CD4+ but not CD8+ T cells from immunized donor mice were sufficient for eliminating Chlamydia from the small intestine but not the large intestine of recipient mice. Thus, we have demonstrated a critical role for Th1 immunity in clearing Chlamydia from the small intestine but not the large intestine, indicating that chlamydial colonization in different regions of the gastrointestinal tract is regulated by distinct immune mechanisms.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por Chlamydia/imunologia , Chlamydia muridarum/imunologia , Interferon gama/imunologia , Intestino Grosso/imunologia , Intestino Delgado/imunologia , Animais , Infecções por Chlamydia/genética , Infecções por Chlamydia/microbiologia , Chlamydia muridarum/genética , Chlamydia muridarum/fisiologia , Feminino , Humanos , Interferon gama/genética , Interleucinas/genética , Interleucinas/imunologia , Intestino Grosso/microbiologia , Intestino Delgado/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Células Th1/imunologia
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