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1.
Gastroenterology ; 155(4): 1004-1007, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29964041

RESUMO

Prebiotics and diets low in fermentable oligo-, di-, mono-saccharides and polyols (low-FODMAP diet) might reduce symptoms in patients with functional gastrointestinal disorders, despite reports that some nonabsorbable, fermentable meal products (prebiotics) provide substrates for colonic bacteria and thereby increase gas production. We performed a randomized, parallel, double-blind study of patients with functional gastrointestinal disorders with flatulence. We compared the effects of a prebiotic supplement (2.8 g/d Bimuno containing 1.37 g beta-galactooligosaccharide) plus a placebo (Mediterranean-type diet (prebiotic group, n = 19) vs a placebo supplement (2.8 g xylose) plus a diet low in FODMAP (low-FODMAP group, n = 21) for 4 weeks; patients were then followed for 2 weeks. The primary outcome was effects on composition of the fecal microbiota, analyzed by 16S sequencing. Secondary outcomes were intestinal gas production and digestive sensations. After 4 weeks, we observed opposite effects on microbiota in each group, particularly in relation to the abundance of Bifidobacterium sequences (increase in the prebiotic group and decrease in the low-FODMAP group; P = .042), and Bilophila wadsworthia (decrease in the prebiotic group and increase in the low-FODMAP group; P = .050). After 4 weeks, both groups had statistically significant reductions in all symptom scores, except reductions in flatulence and borborygmi were not significant in the prebiotic group. Although the decrease in symptoms persisted for 2 weeks after patients discontinued prebiotic supplementation, symptoms reappeared immediately after patients discontinued the low-FODMAP diet. Intermittent prebiotic administration might therefore be an alternative to dietary restrictions for patients with functional gut symptoms. ClinicalTrials.gov no.: NCT02210572.


Assuntos
Bactérias/metabolismo , Dieta com Restrição de Carboidratos , Carboidratos da Dieta/administração & dosagem , Fermentação , Gastroenteropatias/dietoterapia , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Prebióticos , Dieta com Restrição de Carboidratos/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Carboidratos da Dieta/metabolismo , Método Duplo-Cego , Europa (Continente) , Gastroenteropatias/diagnóstico , Gastroenteropatias/metabolismo , Gastroenteropatias/microbiologia , Humanos , Prebióticos/efeitos adversos , Recidiva , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
2.
Synapse ; 70(3): 121-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26682524

RESUMO

Compelling data suggest that perturbations in microbial colonization of the gut in early-life, influences neurodevelopment and adult brain function. If this is the case, then ensuring the growth of beneficial bacteria at an early age will lead to optimal brain development and maturation. We have tested whether feeding neonatal rats daily (from post-natal days 3-21) with a galacto-oligosaccharide prebiotic (Bimuno®, BGOS) or a control solution, alters the levels of hippocampal N-Methyl-D-Aspartate receptor (NMDAR) subunits (GluN1, GluN2A, GluN2B), synaptic proteins (synaptophysin, MAP2, and GAP43) and brain-derived-neurotrophic factor (BDNF), at post-natal days 22 and 56. The administration of BGOS significantly elevated GluN2A subunits, synaptophysin and BDNF in the hippocampus of 22 day old rats. The effect was also observed on day 56 (26 days after the feeding ceased). The levels of all other proteins (GluN1, GluN2B, MAP2, GAP43) remained unaltered. Increased GluN2A, synaptophysin, BDNF, but not MAP2, may suggest that neonatal BGOS feeding alters neurotransmission rather than synaptic architecture. Although the functional consequences of our findings require further investigation, the current study confirms that the manipulation of gut bacteria in early-life, has central effects that persist until at least young adulthood.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Suplementos Nutricionais , Hipocampo/metabolismo , Prebióticos/administração & dosagem , Receptores de N-Metil-D-Aspartato/metabolismo , Sinaptofisina/metabolismo , Administração Oral , Animais , Animais Recém-Nascidos , Western Blotting , Feminino , Proteína GAP-43/metabolismo , Hipocampo/crescimento & desenvolvimento , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Ratos Sprague-Dawley
3.
Brain Behav Immun ; 52: 120-131, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26476141

RESUMO

The manipulation of the enteric microbiota with specific prebiotics and probiotics, has been shown to reduce the host's inflammatory response, alter brain chemistry, and modulate anxiety behaviour in both rodents and humans. However, the neuro-immune and behavioural effects of prebiotics on sickness behaviour have not been explored. Here, adult male CD1 mice were fed with a specific mix of non-digestible galacto-oligosaccharides (Bimuno®, BGOS) for 3 weeks, before receiving a single injection of lipopolysaccharide (LPS), which induces sickness behaviour and anxiety. Locomotor and marble burying activities were assessed 4h after LPS injection, and after 24h, anxiety in the light-dark box was assessed. Cytokine expression, and key components of the serotonergic (5-Hydroxytryptamine, 5-HT) and glutamatergic system were evaluated in the frontal cortex to determine the impact of BGOS administration at a molecular level. BGOS-fed mice were less anxious in the light-dark box compared to controls 24h after the LPS injection. Elevated cortical IL-1ß concentrations in control mice 28 h after LPS were not observed in BGOS-fed animals. This significant BGOS×LPS interaction was also observed for 5HT2A receptors, but not for 5HT1A receptors, 5HT, 5HIAA, NMDA receptor subunits, or other cytokines. The intake of BGOS did not influence LPS-mediated reductions in marble burying behaviour, and its effect on locomotor activity was equivocal. Together, our data show that the prebiotic BGOS has an anxiolytic effect, which may be related to the modulation of cortical IL-1ß and 5-HT2A receptor expression. Our data suggest a potential role for prebiotics in the treatment of neuropsychiatric disorders where anxiety and neuroinflammation are prominent clinical features.


Assuntos
Ansiedade/dietoterapia , Comportamento de Doença/efeitos dos fármacos , Interleucina-1beta/metabolismo , Prebióticos/administração & dosagem , Receptor 5-HT2A de Serotonina/metabolismo , Animais , Ansiedade/induzido quimicamente , Ansiedade/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Lobo Frontal/metabolismo , Microbioma Gastrointestinal , Hipocampo/metabolismo , Inflamação/induzido quimicamente , Inflamação/dietoterapia , Inflamação/psicologia , Lipopolissacarídeos/administração & dosagem , Masculino , Camundongos , Receptores de N-Metil-D-Aspartato/metabolismo , Serotonina/metabolismo
4.
Br J Nutr ; 114(4): 586-95, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26218845

RESUMO

It is recognised that ageing induces various changes to the human colonic microbiota. Most relevant is a reduction in bifidobacteria, which is a health-positive genus. Prebiotics, such as galacto-oligosaccharides (GOS), are dietary ingredients that selectively fortify beneficial gut microbial groups. Therefore, they have the potential to reverse the age-related decline in bifidobacteria and modulate associated health parameters. We assessed the effect of GOS mixture (Bimuno (B-GOS)) on gut microbiota, markers of immune function and metabolites in forty elderly (age 65-80 years) volunteers in a randomised, double-blind, placebo (maltodextrin)-controlled, cross-over study. The intervention periods consisted of 10 weeks with daily doses of 5·5 g/d with a 4-week washout period in between. Blood and faecal samples were collected for the analyses of faecal bacterial populations and immune and metabolic biomarkers. B-GOS consumption led to significant increases in bacteroides and bifidobacteria, the latter correlating with increased lactic acid in faecal waters. Higher IL-10, IL-8, natural killer cell activity and C-reactive protein and lower IL-1ß were also observed. Administration of B-GOS to elderly volunteers may be useful in positively affecting the microbiota and some markers of immune function associated with ageing.


Assuntos
Envelhecimento/imunologia , Bactérias/crescimento & desenvolvimento , Trato Gastrointestinal/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Oligossacarídeos/farmacologia , Prebióticos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Bacteroides/crescimento & desenvolvimento , Bifidobacterium/crescimento & desenvolvimento , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Fezes/microbiologia , Feminino , Galactose/farmacologia , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Sistema Imunitário/metabolismo , Sistema Imunitário/microbiologia , Interleucinas/sangue , Células Matadoras Naturais/metabolismo , Ácido Láctico/metabolismo , Masculino , Metabolômica
5.
J Nutr ; 143(3): 324-31, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23303873

RESUMO

Metabolic syndrome is a set of disorders that increases the risk of developing cardiovascular disease. The gut microbiota is altered toward a less beneficial composition in overweight adults and this change can be accompanied by inflammation. Prebiotics such as galactooligosaccharides can positively modify the gut microbiota and immune system; some may also reduce blood lipids. We assessed the effect of a galactooligosaccharide mixture [Bi2muno (B-GOS)] on markers of metabolic syndrome, gut microbiota, and immune function in 45 overweight adults with ≥3 risk factors associated with metabolic syndrome in a double-blind, randomized, placebo (maltodextrin)-controlled, crossover study (with a 4-wk wash-out period between interventions). Whole blood, saliva, feces, and anthropometric measurements were taken at the beginning, wk 6, and end of each 12-wk intervention period. Predominant groups of fecal bacteria were quantified and full blood count, markers of inflammation and lipid metabolism, insulin, and glucose were measured. B-GOS increased the number of fecal bifidobacteria at the expense of less desirable groups of bacteria. Increases in fecal secretory IgA and decreases in fecal calprotectin, plasma C-reactive protein, insulin, total cholesterol (TC), TG, and the TC:HDL cholesterol ratio were also observed. Administration of B-GOS to overweight adults resulted in positive effects on the composition of the gut microbiota, the immune response, and insulin, TC, and TG concentrations. B-GOS may be a useful candidate for the enhancement of gastrointestinal health, immune function, and the reduction of metabolic syndrome risk factors in overweight adults.


Assuntos
Bactérias/efeitos dos fármacos , Galactose/uso terapêutico , Imunidade/efeitos dos fármacos , Síndrome Metabólica/tratamento farmacológico , Oligossacarídeos/uso terapêutico , Sobrepeso/tratamento farmacológico , Prebióticos , Adulto , Bactérias/crescimento & desenvolvimento , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/crescimento & desenvolvimento , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Fezes/química , Fezes/microbiologia , Feminino , Galactose/farmacologia , Humanos , Imunoglobulina A/metabolismo , Inflamação/sangue , Inflamação/prevenção & controle , Insulina/sangue , Complexo Antígeno L1 Leucocitário/metabolismo , Lipídeos/sangue , Masculino , Síndrome Metabólica/metabolismo , Metagenoma/efeitos dos fármacos , Pessoa de Meia-Idade , Oligossacarídeos/farmacologia , Sobrepeso/imunologia , Sobrepeso/metabolismo , Sobrepeso/microbiologia , Fatores de Risco
6.
Biomacromolecules ; 14(2): 387-93, 2013 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-23301617

RESUMO

If acid-sensitive drugs or cells are administered orally, there is often a reduction in efficacy associated with gastric passage. Formulation into a polymer matrix is a potential method to improve their stability. The visualization of pH within these materials may help better understand the action of these polymer systems and allow comparison of different formulations. We herein describe the development of a novel confocal laser-scanning microscopy (CLSM) method for visualizing pH changes within polymer matrices and demonstrate its applicability to an enteric formulation based on chitosan-coated alginate gels. The system in question is first shown to protect an acid-sensitive bacterial strain to low pH, before being studied by our technique. Prior to this study, it has been claimed that protection by these materials is a result of buffering, but this has not been demonstrated. The visualization of pH within these matrices during exposure to a pH 2.0 simulated gastric solution showed an encroachment of acid from the periphery of the capsule, and a persistence of pHs above 2.0 within the matrix. This implies that the protective effect of the alginate-chitosan matrices is most likely due to a combination of buffering of acid as it enters the polymer matrix and the slowing of acid penetration.


Assuntos
Alginatos/química , Bifidobacterium/efeitos dos fármacos , Cápsulas/química , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Trato Gastrointestinal/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Microscopia Confocal/métodos , Polímeros/química
7.
Front Microbiol ; 14: 1273861, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075921

RESUMO

This study evaluated the effects of dietary supplementation with a postbiotic extract of Bifidobacterium breve BB091109 on pro-inflammatory cytokines levels and markers of endocrine function. A prospective, double-blind, placebo-controlled, randomized, single-centered, parallel study was conducted on a group of 40-55-year-old females. The study included 30 healthy females, divided into two groups: a supplement (n = 20) and a placebo (n = 10) groups. Blood and saliva samples were collected at baseline (wk0), after 4 weeks (wk 4) and 12 weeks (12wk) of daily supplementation (500 mg), and 4 weeks (wk 16) after termination of supplementation. The levels of fasting CRP, IL-6, IL-10, TNF-α, IFN-γ, DHEA, estradiol, estriol, progesterone, cortisol and human growth hormone were analysed. The results revealed a significant effect of the 90-day supplementation with B. breve postbiotic extract on changes in CRP, IL-6 levels, DHEA, estradiol and estriol. In conclusion, the supplementation with the B. breve postbiotic extract improved endocrine function in females over 40 years old and induced protective changes in inflammatory markers. These findings highlight the potential health benefits of this supplementation in promoting hormonal balance and reducing inflammation in this population.

8.
Cureus ; 14(5): e25211, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35747007

RESUMO

Schwannomas of the head and neck are relatively rare benign tumors that derive from the Schwann cells. Schwannomas are usually asymptomatic; however, tumors of bigger size may produce unspecific symptoms due to compression of the adjacent anatomic structures. Vagus nerve schwannomas may present as solitary neck masses, produce hoarseness of voice, or induce paroxysmal cough on palpation, which is also pathognomonic. Preoperative diagnosis is challenging and imaging studies may play a vital role in the diagnosis. Surgical treatment with complete tumor removal is the treatment of choice. In this study, we present a case of vagus nerve schwannoma in an adult male patient.

9.
Biomacromolecules ; 12(7): 2834-40, 2011 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21574635

RESUMO

This study investigates the production of alginate microcapsules, which have been coated with the polysaccharide chitosan, and evaluates some of their properties with the intention of improving the gastrointestinal viability of a probiotic ( Bifidobacterium breve ) by encapsulation in this system. The microcapsules were dried by a variety of methods, and the most suitable was chosen. The work described in this Article is the first report detailing the effects of drying on the properties of these microcapsules and the viability of the bacteria within relative to wet microcapsules. The pH range over which chitosan and alginate form polyelectrolyte complexes was explored by spectrophotometry, and this extended into swelling studies on the microcapsules over a range of pHs associated with the gastrointestinal tract. It was shown that chitosan stabilizes the alginate microcapsules at pHs above 3, extending the stability of the capsules under these conditions. The effect of chitosan exposure time on the coating thickness was investigated for the first time by confocal laser scanning microscopy, and its penetration into the alginate matrix was shown to be particularly slow. Coating with chitosan was found to increase the survival of B. breve in simulated gastric fluid as well as prolong its release upon exposure to intestinal pH.


Assuntos
Alginatos/química , Bifidobacterium/química , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Cápsulas/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio
10.
Acta Medica (Hradec Kralove) ; 64(4): 224-226, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35285445

RESUMO

Cystic lymphangioma (CL) is a rare benign tumour that arises from the lymphatic vessels. The most common site of presentation is the posterior triangle of the neck. 90% of the lesions are diagnosed before the age of two years old and only a small number is reported in adults. In this paper, we describe the diagnostic and treatment approach of a cervical CL in an adult male.


Assuntos
Linfangioma Cístico , Adulto , Pré-Escolar , Humanos , Linfangioma Cístico/diagnóstico por imagem , Linfangioma Cístico/cirurgia , Masculino , Pescoço
11.
J Med Microbiol ; 58(Pt 1): 37-48, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19074651

RESUMO

The prebiotic Bimuno is a mixture containing galactooligosaccharide, produced by the galactosyltransferase activity of Bifidobacterium bifidum NCIMB 41171 in the presence of lactose. Previous studies have implicated prebiotics in reducing infections by enteric pathogens, thus it was hypothesized that Bimuno may confer some protection in the murine host from Salmonella enterica serovar Typhimurium (S. Typhimurium) infection. In this study, infection caused by S. Typhimurium SL1344nal(r) in the presence or absence of Bimuno was assessed using tissue culture assays, a murine ligated ileal gut loop model and a murine oral challenge model. In tissue culture adherence and invasion assays with HT-29-16E cells, the presence of approximately 2 mM Bimuno significantly reduced the invasion of S. Typhimurium SL1344nal(r) (P<0.0001). In the murine ligated ileal gut loops, the presence of Bimuno prevented colonization and the associated pathology of S. Typhimurium. In the BALB/c mouse model, the oral delivery of Bimuno prior to challenge with S. Typhimurium resulted in significant reductions in colonization in the five organs sampled, with highly significant reductions being observed in the spleen at 72 and 96 h post-challenge (P=0.0002, <0.0001, respectively). Collectively, the results indicate that Bimuno significantly reduced the colonization and pathology associated with S. Typhimurium infection in a murine model system, possibly by reducing the invasion of the pathogen into host cells.


Assuntos
Bifidobacterium/enzimologia , Oligossacarídeos/uso terapêutico , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Animais , Fezes/microbiologia , Feminino , Células HT29 , Humanos , Íleo/microbiologia , Íleo/patologia , Íleo/ultraestrutura , Fígado/microbiologia , Camundongos , Baço/microbiologia
12.
Appl Microbiol Biotechnol ; 82(3): 471-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19005653

RESUMO

A genomic library of Bifidobacterium bifidum (NCIMB 41171) DNA was constructed in Escherichia coli RA11r (melA(-)B(+)) and one alpha-galactosidase encoding gene was isolated. Conceptual translation combined with insertional mutagenesis analysis indicated an open reading frame (ORF) of 759 amino acid (aa) residues encoding an alpha-galactosidase (named as MelA) of 82.8 kDa. Partial purification and characterisation showed that the enzyme had an apparent native molecular mass of approximately 243 kDa and a subunit size of approximately 85 kDa. The enzyme belongs to glycosyl hydrolases 36 family with high aa sequence similarities (approximately 73%) to other known alpha-galactosidases of bifidobacterial origin. Under optimum pH conditions for activity (pH 6.0) and high melibiose concentration (40% w/v), the enzyme was able to form oligosaccharides with degree of polymerisation (DP) > or = 3 at higher concentration than DP = 2, with a total yield of 20.5% (w/w).


Assuntos
Proteínas de Bactérias/metabolismo , Bifidobacterium/enzimologia , Bifidobacterium/genética , Clonagem Molecular , Expressão Gênica , alfa-Galactosidase/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Bifidobacterium/química , Escherichia coli/genética , Escherichia coli/metabolismo , Dados de Sequência Molecular , Peso Molecular , Fases de Leitura Aberta , Alinhamento de Sequência , alfa-Galactosidase/química , alfa-Galactosidase/genética , alfa-Galactosidase/isolamento & purificação
13.
Appl Microbiol Biotechnol ; 82(6): 1079-88, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19099301

RESUMO

Four different beta-galactosidases (previously named BbgI, BbgII, BbgIII and BbgIV) from Bifidobacterium bifidum NCIMB41171 were overexpressed in Escherichia coli, purified to homogeneity and their biochemical properties and substrate preferences comparatively analysed. BbgI was forming a hexameric protein complex of 875 kDa, whereas BbgII, BbgIII and BbgIV were dimers with native molecular masses of 178, 351 and 248 kDa, respectively. BbgII was the only enzyme that preferred acidic conditions for optimal activity (pH 5.4-5.8), whereas the other three exhibited optima in more neutral pH ranges (pH 6.4-6.8). Na(+) and/or K(+) ions were prerequisite for BbgI and BbgIV activity in Bis-Tris-buffered solutions, whereas Mg(++) was strongly activating them in phosphate-buffered solutions. BbgII and BbgIII were slightly influenced from the presence or absence of cations, with Mg(++), Mn(++) and Ca(++) ions exerting the most positive effect. Determination of the specificity constants (k(cat)/K(m)) clearly indicated that BbgI (6.11 x 10(4) s(-1) M(-1)), BbgIII (2.36 x 10(4) s(-1) M(-1)) and especially BbgIV (4.01 x 10(5) s(-1) M(-1)) are highly specialised in the hydrolysis of lactose, whereas BbgII is more specific for beta-D-(1-->6) galactobiose (5.59 x 10(4) s(-1) M(-1)) than lactose (1.48 x 10(3) s(-1) M(-1)). Activity measurements towards other substrates (e.g. beta-D-(1-->6) galactobiose, beta-D-(1-->4) galactobiose, beta-D-(1-->4) galactosyllactose, N-acetyllactosamine, etc.) indicated that the beta-galactosidases were complementary to each other by hydrolysing different substrates and thus contributing in a different way to the bacterial physiology.


Assuntos
Bifidobacterium/enzimologia , beta-Galactosidase/isolamento & purificação , beta-Galactosidase/metabolismo , Amino Açúcares/metabolismo , Bifidobacterium/genética , Cátions/farmacologia , Cátions Bivalentes/farmacologia , Clonagem Molecular , Coenzimas/farmacologia , Dissacarídeos/metabolismo , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Escherichia coli/genética , Expressão Gênica , Concentração de Íons de Hidrogênio , Lactose/metabolismo , Metais/farmacologia , Peso Molecular , Multimerização Proteica , Especificidade por Substrato
14.
Appl Microbiol Biotechnol ; 84(5): 899-907, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19434405

RESUMO

This paper deals with two aspects tightly related to the enzymatic characteristics and expression of four beta-galactosidases (BbgI, BbgII, BbgIII and BbgIV) from Bifidobacterium bifidum NCIMB41171. The growth patterns of this strain indicated a preference towards complex (i.e. lactose, galactooligosaccharides (GOSs)) rather than simple carbohydrates (i.e. glucose and galactose) and a collaborative action and synergistic relation of more than one beta-galactosidase isoenzyme for either lactose or GOS hydrolysis and subsequent assimilation. Native polyacrylamide gel electrophoresis analysis of protein extracts from cells growing on different carbohydrates (i.e. glucose, lactose or GOS) indicated that two lactose hydrolysing enzymes (BbgI and BbgIII) and one GOS hydrolysing enzyme (BbgII) were constitutively expressed, whereas a fourth lactose hydrolysing enzyme (BbgIV) was induced in the presence of lactose or different GOS fractions. Furthermore, the beta-galactosidase expression profiles of B. bifidum cells and the transgalactosylating properties of each individual isoenzyme, with lactose as substrate, clearly indicated that mainly three isoenzymes (BbgI, BbgIII and BbgIV) are implicated in GOS synthesis when whole B. bifidum cells are utilised. Two of the isoenzymes (BbgI and BbgIV) proved to have better transgalactosylating properties giving yields ranging from 42% to 47% whereas the rest (BbgI and BbgIII) showed lower yields (15% and 29%, respectively).


Assuntos
Proteínas de Bactérias/metabolismo , Bifidobacterium/enzimologia , Regulação Enzimológica da Expressão Gênica , Oligossacarídeos/biossíntese , beta-Galactosidase/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Bifidobacterium/química , Bifidobacterium/genética , Regulação Bacteriana da Expressão Gênica , Hidrólise , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Oligossacarídeos/química , Especificidade por Substrato , beta-Galactosidase/química , beta-Galactosidase/genética , beta-Galactosidase/isolamento & purificação
15.
Neurogastroenterol Motil ; 30(11): e13440, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30109908

RESUMO

BACKGROUND: Prebiotics exert beneficial effects upon gastrointestinal (GI) environment, but this is not always accompanied with a positive effect on GI symptoms. B-GOS® is a prebiotic with high selectivity toward bifidobacteria and a variety of other beneficial effects in humans. Here, we investigated its effect on GI symptoms in adults who suffer with bloating, abdominal pain, and flatulence. METHODS: In a double-blind, placebo-controlled, crossover study, 83 subjects from the general population who presented with GI symptoms during screening period and had a predicted probability of functional bowel disorder of more than 75% were randomized to receive either a placebo or the B-GOS® treatment (2.75 g/d). Subjects were screened for the presence of GI symptoms for 1 week, they consumed the treatments for 2 weeks, and then went through a 2-week washout period, before switching to the other treatment for the final 2 weeks. GI symptoms, bowel movements, and stool consistency were assessed in daily and weekly questionnaires. Quality of life was assessed weekly and depression and anxiety at the end of each treatment period. RESULTS: B-GOS® resulted in significantly (P < 0.001) lower scores for bloating, flatulence, and abdominal pain both from baseline and placebo at the end of first week. The effect was sustained at the end of second week. It had no effect on the number of bowel movements, consistency of stools, quality of life, or mood throughout the study. CONCLUSION: Results suggest that B-GOS® could possibly be used in the management of bloating, flatulence, or abdominal pain and warrant further investigation.


Assuntos
Dor Abdominal , Flatulência , Prebióticos , Adulto , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Galactose/farmacologia , Humanos , Masculino
16.
Eur Neuropsychopharmacol ; 28(1): 211-224, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29174530

RESUMO

We have previously shown that prebiotics (dietary fibres that augment the growth of indigenous beneficial gut bacteria) such as Bimuno™ galacto-oligosaccharides (B-GOS®), increased N-methyl-D-aspartate (NMDA) receptor levels in the rat brain. The current investigation examined the functional correlates of these changes in B-GOS®-fed rats by measuring cortical neuronal responses to NMDA using in vivo NMDA micro-iontophoresis electrophysiology, and performance in the attentional set-shifting task. Adult male rats were supplemented with B-GOS® in the drinking water 3 weeks prior to in vivo iontophoresis or behavioural testing. Cortical neuronal responses to NMDA iontophoresis, were greater (+30%) in B-GOS® administered rats compared to non-supplemented controls. The intake of B-GOS® also partially hindered the reduction of NMDA responses by the glycine site antagonist, HA-966. In the attentional set-shifting task, B-GOS® -fed rats shifted from an intra-dimensional to an extra-dimensional set in fewer trials than controls, thereby indicating greater cognitive flexibility. An initial exploration into the mechanisms revealed that rats ingesting B-GOS® had increased levels of plasma acetate, and cortical GluN2B subunits and Acetyl Co-A Carboxylase mRNA. These changes were also observed in rats fed daily for 3 weeks with glyceryl triacetate, though unlike B-GOS®, cortical histone deacetylase (HDAC1, HDAC2) mRNAs were also increased which suggested an additional epigenetic action of direct acetate supplementation. Our data demonstrate that a pro-cognitive effect of B-GOS® intake in rats is associated with an increase in cortical NMDA receptor function, but the role of circulating acetate derived from gut bacterial fermentation of this prebiotic requires further investigation.


Assuntos
Atenção/fisiologia , Córtex Cerebral/metabolismo , Suplementos Nutricionais , N-Metilaspartato/metabolismo , Neurônios/metabolismo , Prebióticos/administração & dosagem , Animais , Córtex Cerebral/efeitos dos fármacos , Função Executiva/fisiologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Neurotransmissores/farmacologia , Distribuição Aleatória , Ratos Sprague-Dawley , Triglicerídeos/administração & dosagem
17.
FEMS Microbiol Ecol ; 93(2)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27856622

RESUMO

Children with autism spectrum disorders (ASD) often suffer gastrointestinal problems consistent with imbalances in the gut microbial population. Treatment with antibiotics or pro/prebiotics has been postulated to regulate microbiota and improve gut symptoms, but there is a lack of evidence for such approaches, especially for prebiotics. This study assessed the influence of a prebiotic galactooligosaccharide (B-GOS) on gut microbial ecology and metabolic function using faecal samples from autistic and non-autistic children in an in vitro gut model system. Bacteriology was analysed using flow cytometry combined with fluorescence in situ hybridization and metabolic activity by HPLC and 1H-NMR. Consistent with previous studies, the microbiota of children with ASD contained a higher number of Clostridium spp. and a lower number of bifidobacteria compared with non-autistic children. B-GOS administration significantly increased bifidobacterial populations in each compartment of the models, both with autistic and non-autistic-derived samples, and lactobacilli in the final vessel of non-autistic models. In addition, changes in other bacterial population have been seen in particular for Clostridium, Rosburia, Bacteroides, Atopobium, Faecalibacterium prausnitzii, Sutterella spp. and Veillonellaceae. Furthermore, the addition of B-GOS to the models significantly altered short-chain fatty acid production in both groups, and increased ethanol and lactate in autistic children.


Assuntos
Transtorno Autístico/microbiologia , Criança , Fezes/microbiologia , Fermentação , Prebióticos , Antibacterianos , Bacteroides/metabolismo , Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Clostridium/metabolismo , Ácidos Graxos Voláteis/metabolismo , Humanos , Hibridização in Situ Fluorescente , Ácido Láctico , Lactobacillus/metabolismo , Microbiota , Oligossacarídeos/metabolismo
18.
Psychopharmacology (Berl) ; 232(10): 1793-801, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25449699

RESUMO

RATIONALE: There is now compelling evidence for a link between enteric microbiota and brain function. The ingestion of probiotics modulates the processing of information that is strongly linked to anxiety and depression, and influences the neuroendocrine stress response. We have recently demonstrated that prebiotics (soluble fibres that augment the growth of indigenous microbiota) have significant neurobiological effects in rats, but their action in humans has not been reported. OBJECTIVES: The present study explored the effects of two prebiotics on the secretion of the stress hormone, cortisol and emotional processing in healthy volunteers. METHODS: Forty-five healthy volunteers received one of two prebiotics (fructooligosaccharides, FOS, or Bimuno®-galactooligosaccharides, B-GOS) or a placebo (maltodextrin) daily for 3 weeks. The salivary cortisol awakening response was sampled before and after prebiotic/placebo administration. On the final day of treatment, participants completed a computerised task battery assessing the processing of emotionally salient information. RESULTS: The salivary cortisol awakening response was significantly lower after B-GOS intake compared with placebo. Participants also showed decreased attentional vigilance to negative versus positive information in a dot-probe task after B-GOS compared to placebo intake. No effects were found after the administration of FOS. CONCLUSION: The suppression of the neuroendocrine stress response and the increase in the processing of positive versus negative attentional vigilance in subjects supplemented with B-GOS are consistent with previous findings of endocrine and anxiolytic effects of microbiota proliferation. Further studies are therefore needed to test the utility of B-GOS supplementation in the treatment of stress-related disorders.


Assuntos
Emoções/fisiologia , Hidrocortisona/metabolismo , Prebióticos/administração & dosagem , Vigília/fisiologia , Adolescente , Adulto , Animais , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Oligossacarídeos/administração & dosagem , Estimulação Luminosa/métodos , Ratos , Saliva/metabolismo , Adulto Jovem
19.
PLoS One ; 10(3): e0121955, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25807417

RESUMO

A three-stage continuous fermentative colonic model system was used to monitor in vitro the effect of different orange juice formulations on prebiotic activity. Three different juices with and without Bimuno, a GOS mixture containing galactooligosaccharides (B-GOS) were assessed in terms of their ability to induce a bifidogenic microbiota. The recipe development was based on incorporating 2.75g B-GOS into a 250 ml serving of juice (65°Brix of concentrate juice). Alongside the production of B-GOS juice, a control juice--orange juice without any additional Bimuno and a positive control juice, containing all the components of Bimuno (glucose, galactose and lactose) in the same relative proportions with the exception of B-GOS were developed. Ion Exchange Chromotography analysis was used to test the maintenance of bimuno components after the production process. Data showed that sterilisation had no significant effect on concentration of B-GOS and simple sugars. The three juice formulations were digested under conditions resembling the gastric and small intestinal environments. Main bacterial groups of the faecal microbiota were evaluated throughout the colonic model study using 16S rRNA-based fluorescence in situ hybridization (FISH). Potential effects of supplementation of the juices on microbial metabolism were studied measuring short chain fatty acids (SCFAs) using gas chromatography. Furthermore, B-GOS juices showed positive modulations of the microbiota composition and metabolic activity. In particular, numbers of faecal bifidobacteria and lactobacilli were significantly higher when B-GOS juice was fermented compared to controls. Furthermore, fermentation of B-GOS juice resulted in an increase in Roseburia subcluster and concomitantly increased butyrate production, which is of potential benefit to the host. In conclusion, this study has shown B-GOS within orange juice can have a beneficial effect on the fecal microbiota.


Assuntos
Bifidobacterium , Citrus sinensis , Colo/microbiologia , Microbiota/efeitos dos fármacos , Modelos Biológicos , Prebióticos/análise , Adulto , Feminino , Fermentação , Humanos , Masculino
20.
Gut Microbes ; 6(5): 300-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26099034

RESUMO

Prebiotics are dietary carbohydrates that favourably modulate the gut microbiota. The aims of the present study were to develop a functional prebiotic bread using Bimuno®, (galactooligosaccharide (B-GOS) mixture), for modulation of the gut microbiota in vitro in individuals at risk of metabolic syndrome. A control bread, (no added prebiotic) and positive control bread (containing equivalent carbohydrate to B-GOS bread) were also developed. A 3-stage continuous in vitro colonic model was used to assess prebiotic functionality of the breads. Bacteria were quantified by fluorescence in situ hybridization and short chain fatty acids by gas chromatography. Ion-exchange chromatography was used to determine GOS concentration after bread production. Following B-GOS bread fermentation numbers of bifidobacteria and lactobacilli were significantly higher compared to controls. There was no significant degradation of B-GOS during bread manufacture, indicating GOS withstood the manufacturing process. Furthermore, based on previous research, increased bifidobacteria and butyrate levels could be of benefit to those with obesity related conditions. Our findings support utilization of prebiotic enriched bread for improving gastrointestinal health.


Assuntos
Pão , Colo/química , Colo/microbiologia , Dietoterapia/métodos , Portadores de Fármacos/administração & dosagem , Síndrome Metabólica/terapia , Prebióticos/administração & dosagem , Carga Bacteriana , Bifidobacterium/isolamento & purificação , Cromatografia Gasosa , Cromatografia por Troca Iônica , Ácidos Graxos Voláteis/análise , Hibridização in Situ Fluorescente , Lactobacillus/isolamento & purificação , Modelos Biológicos , Oligossacarídeos/análise
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