Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D04346 (Bifidobacterium)
 5,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bifidobacterium, which is a dominant genus in infants' fecal flora and can be used as a probiotic, has shown beneficial effects in various pathologies, including allergic diseases, but its role in immunity has so far been little known. Numerous studies have shown the crucial role of the initial intestinal colonization in the development of the intestinal immune system, and bifidobacteria could play a major role in this process. For a better understanding of the effect of Bifidobacterium on the immune system, we aimed at determining the impact of Bifidobacterium on the T-helper 1 (T(H)1)/T(H)2 balance by using gnotobiotic mice. Germfree mice were inoculated with Bifidobacterium longum NCC2705, whose genome is sequenced, and with nine Bifidobacterium strains isolated from infants' fecal flora. Five days after inoculation, mice were killed. Transforming growth factor beta1 (TGF-beta1), interleukin-4 (IL-4), IL-10, and gamma interferon (IFN-gamma) gene expressions in the ileum and IFN-gamma, tumor necrosis factor alpha (TNF-alpha), IL-10, IL-4, and IL-5 secretions by splenocytes cultivated for 48 h with concanavalin A were quantified. Two Bifidobacterium species had no effect (B. adolescentis) or little effect (B. breve) on the immune system. Bifidobacterium bifidum, Bifidobacterium dentium, and one B. longum strain induced T(H)1 and T(H)2 cytokines at the systemic and intestinal levels. One B. longum strain induced a T(H)2 orientation with high levels of IL-4 and IL-10, both secreted by splenocytes, and of TGF-beta gene expression in the ileum. The other two strains induced T(H)1 orientations with high levels of IFN-gamma and TNF-alpha splenocyte secretions. Bifidobacterium's capacity to stimulate immunity is species specific, but its influence on the orientation of the immune system is strain specific.
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PMID:Gnotobiotic mouse immune response induced by Bifidobacterium sp. strains isolated from infants. 1808 75

Faecal and serum samples were collected over a period of 6 months from 55 institutionalized elderly subjects, who were enrolled in a double-blind placebo-controlled study. Participants were randomized in one of the three treatment groups: intervention (two probiotic Bifidobacterium longum strains: 2C and 46), placebo and commercial control (Bifidobacterium lactis Bb-12). The faecal Bifidobacterium microbiota was characterized by genus and species-specific PCR. Serum levels of the cytokines IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1 were determined by enzyme-linked immunosorbent assay. Each participant harboured on average approximately three different bifidobacterial species. The most frequently detected species were B. longum, Bifidobacterium adolescentis and Bifidobacterium bifidum. Depending on the treatment, the intervention resulted in specific changes in the levels of certain Bifidobacterium species, and positive correlations were found between the different species. Negative correlations were observed between the levels of Bifidobacterium species and the pro-inflammatory cytokine TNF-alpha and the regulatory cytokine IL-10. The presence of faecal B. longum and Bifidobacterium animalis correlated with reduced serum IL-10. The anti-inflammatory TGF-beta1 levels were increased over time in all three groups, and the presence of Bifidobacterium breve correlated with higher serum TGF-beta1 levels. This indicates that modulation of the faecal Bifidobacterium microbiota may provide a means of influencing inflammatory responses.
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PMID:Bifidobacterium microbiota and parameters of immune function in elderly subjects. 1833 47

Commensal gut bacteria have potent effects on the immune system, which are partially mediated by intestinal dendritic cells (DC). Distinct commensals confer different properties to in vitro-generated DC. The aim of the present study was to reveal strain-dependent maturation patterns in primary DC. To this end, we compared the response of mouse Peyer's patch (PP) DC, mesenteric lymph node (MLN) DC and spleen DC to the commensal bacteria, Bifidobacterium longum Q46, Lactobacillus acidophilus X37 and Escherichia coli Nissle 1917. Bacterial maturation of DC occurred independently of tissue origin. Expression of CCR7 and CD103 on the surface of MLN DC, necessary for the induction of gut-homing regulatory T cells, increased with stimulation by Gram-positive commensals. Bacteria-dependent cytokine production (IL-6, IL-10 and TNF-alpha) was similar in spleen and MLN DC, and contaminant cells in these DC preparations produced IFN-gamma in response to L. acidophilus. In contrast, PP DC produced IL-6 only in response to E. coli, little IL-10 and no TNF-alpha, and this low cytokine production was not due to inhibition by IL-10 or TGF-beta. Bifidobacteria downregulate IL-6, TNF-alpha and IL-12 production induced in in vitro-generated DC by L. acidophilus. Similar inhibition was observed in splenic DC, but not in MLN DC. MLN cells responded to bacterial stimulation with higher IFN-gamma production than spleen cells, possibly due to the presence of more responsive natural killer cells. Commensal bacteria therefore play specific roles in the gut immune system distinguishable from the effect they would have if recognized by the systemic immune system.
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PMID:Dendritic cells from Peyer's patches and mesenteric lymph nodes differ from spleen dendritic cells in their response to commensal gut bacteria. 1856 17

Probiotic bacteria alleviate many gastrointestinal symptoms, but the current trend of combining bacteria for additional benefit may make their effects more complex. We characterize four probiotics and their combination in terms of pathogen adhesion, barrier function, cell death, and inflammatory response in Helicobacter pylori-infected epithelial cells. H. pylori-infected Caco-2 cells were pretreated with Lactobacillus rhamnosus GG, Lactobacillus rhamnosus Lc705, Propionibacterium freudenreichii subsp. shermanii Js, Bifidobacterium breve Bb99, or all four organisms in combination. We evaluated the adhesion of H. pylori by in situ immunofluorescence; epithelial barrier function by measurement of transepithelial resistance; apoptosis by measurement of caspase 3 activation; cell membrane leakage by measurement of lactate dehydrogenase release; and inflammation by measurement of interleukin-8 (IL-8), IL-10, prostaglandin E(2) (PGE(2)), and leukotriene B(4) (LTB(4)) release. All probiotics inhibited H. pylori adhesion. L. rhamnosus GG, L. rhamnosus Lc705, P. freudenreichii subsp. shermanii Js, and the combination inhibited H. pylori-induced cell membrane leakage. L. rhamnosus GG, L. rhamnosus Lc705, and the combination initially improved epithelial barrier function but increased the H. pylori-induced barrier deterioration after incubation for 24 to 42 h. L. rhamnosus GG, L. rhamnosus Lc705, and P. freudenreichii subsp. shermanii Js inhibited H. pylori-induced IL-8 release, whereas L. rhamnosus GG, L. rhamnosus Lc705, and B. breve Bb99 suppressed PGE(2) release. None of these anti-inflammatory effects persisted when the probiotics were used in combination. The combination thus increased the levels of IL-8, PGE(2), and LTB(4) released from H. pylori-infected epithelial cells. The proinflammatory actions of the individual components dominated the anti-inflammatory effects when the probiotic bacteria were used in combination. Our results stress that the therapeutic response can be optimized if probiotic strains are characterized before they are used in combination.
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PMID:Effects of multispecies probiotic combination on helicobacter pylori infection in vitro. 1857 92

Interleukin (IL)-17 acts as a potent inflammatory cytokine, and IL-17-producing cells (Th17 cells) have received much attention. However, the involvement of commensal and/or probiotic bacteria in IL-17 production has not been evaluated. In this study, we examined the suppressive effects of five bacteria species on IL-17 production in vitro and ex vivo. Among the five species studied, Bifidobacterium infantis inhibited IL-17 production but enhanced IL-27 production most potently in TGF-beta plus IL-6-stimulated murine splenocytes. B. infantis also inhibited IL-17 and eotaxin production from a dextran sodium sulfate-treated colon organ culture. The induction of IL-10 by B. infantis was observed both in the splenocytes and in the colon culture and was assumed, to a certain extent, to be important for suppressing IL-17 production. These findings suggest a novel immunomodulatory function of commensal bifidobacteria and further imply that these bacteria may be useful in the treatment of Th17-mediated diseases.
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PMID:Bifidobacterium infantis suppresses proinflammatory interleukin-17 production in murine splenocytes and dextran sodium sulfate-induced intestinal inflammation. 1863 71

Recent study has demonstrated an increasing prevalence of food allergy in Korean children. Specific probiotic bacteria may promote potentially anti-allergenic processes through induction of Th1-type immunity and enhance the regulatory lymphocyte. This study investigated whether orally administrated probiotics could suppress allergic responses in an ovalbumin (OVA)-induced allergy mouse model. Thus, female C3H/HeJ mice were orally sensitized with OVA and cholera toxin for 4 weeks. Lactobacillus acidophilus AD031, Bifidobacterium lactis AD011, and L. acidophilus AD031 plus B. lactis AD011 were fed to mice from 2 weeks before the sensitization. The OVA-induced mice that were not treated with probiotics had significantly increased serum levels of OVA-specific IgE and IgG1, and OVA-specific IgA in feces. However, the mice treated with probiotics suppressed production of the OVA-specific IgE, IgG1, and IgA. The level of IL-4 was significantly lower, and the levels of INF-gamma and IL-10 were significantly higher in the mice treated with probiotics than that in the nontreated mice. The groups treated with probiotics had decreased levels of degranulated mast cells, eosinophil granules, and tail scabs. These results indicate that L. acidophilus AD031 and B. lactis AD011 might be useful for the prevention of allergy.
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PMID:Effect of oral probiotics (Bifidobacterium lactis AD011 and Lactobacillus acidophilus AD031) administration on ovalbumin-induced food allergy mouse model. 1875 99

Although beneficial roles of probiotics for inflammatory bowel diseases have been reported, their direct action on immune cells has not been elucidated. In this study, we investigated how three species of Bifidobacterium and Enterococcus faecalis differentially modulate production of cytokines from lipopolysaccharide (LPS)-stimulated macrophages in vitro using RAW264.7 cells. The mRNA levels of proinflammatory cytokines were remarkably increased after exposure to LPS, E. faecalis alone and LPS combined with E. faecalis. In contrast, IL-10 mRNA levels were significantly decreased after exposure to E. faecalis compared with exposure to Bifidobacterium species. When cells were exposed to Bifidobacterium species combined with LPS, mRNA levels of IL12p40 were decreased by co-culture with B. breve and B. longum, IL-1 beta mRNA levels were decreased by B. breve and B. adorescentis and TNF-alpha mRNA levels were decreased by B. adolescentis compared with LPS alone. The three species of Bifidobacterium significantly inhibited phosphorylation of I kappaB-alpha induced by LPS. The mRNA levels of SOCS1 and SOCS3 were increased by exposure to LPS alone; however, the mRNA levels of SOCS1 or SOCS3 were increased more by exposure to Bifidobacterium species combined with LPS. Conversely, E. faecalis combined with LPS induced significantly lower levels of SOCS mRNA than those induced by Bifidobacterium species combined with LPS. These results indicated that certain species of genus Bifidobacterium could negatively modulate mRNA levels of proinflammatory cytokines produced from LPS-stimulated RAW264.7 cells, which is possibly related to inhibition of I kappaB-alpha phosphorylation and stimulation of SOCS signalling.
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PMID:Anti-inflammatory effects of the genus Bifidobacterium on macrophages by modification of phospho-I kappaB and SOCS gene expression. 1933 51

The Bifidobacterium breve M-16V strain has previously been shown to be effective in infants in improving the symptoms of allergic hypersensitivity to cow's milk and atopic dermatitis. In the current study, we investigated the effect of an oral administration of M-16V on immunoglobulin (Ig) E production in BALB/c mice. Live M-16V was orally administered to ovalbumin (OVA)-immunized mice for 3 weeks at a dose level of 5x10(8) colony-forming unit (cfu)/0.5 ml/d/animal. While M-16V treatment significantly reduced the serum levels of total IgE, OVA-specific IgE and OVA-specific IgG1, as compared to controls, it did not affect the serum level of OVA-specific IgG2a. In M-16V-administered mice, there was a significant decrease in the serum OVA-specific IgG1/IgG2a ratio. In addition, while ex vivo production of interleukin (IL)-4 by the splenocytes from M-16V-administered mice was significantly lower as compared to controls, there was no difference in the production of gamma-interferon (IFN-gamma) and IL-10. We also examined the effect of M-16V on cytokine and IgE production from OVA-sensitized splenocytes via restimulation with OVA in vitro. While M-16V suppressed OVA-induced total IgE and IL-4 production and induced secretion of IFN-gamma and IL-10 in a dose-dependent manner, it was not able to induce IL-12. We concluded that oral administration of M-16V suppressed the T-helper type (Th) 2 immune response and IgE production and modulated the systemic Th1/Th2 balance, and which was at least partially independent of the Th1 cytokine induction. These results suggest that M-16V may potentially have an antiallergic activity.
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PMID:Suppressive effects of bifidobacterium breve strain M-16V on T-helper type 2 immune responses in a murine model. 1933 21

The incidence of allergic diseases has been increasing in industrialized countries during recent years. Although several environmental factors are thought be involved, lack of moderate level of microbial challenges during the infantile period is known to skew the immune status toward the development of allergic diseases. Various strains of probiotics such as Bifidobacterium, Lactobacillus, and Lactococcus have been assessed for their ability to suppress the occurrence of atopic dermatitis (AD) in animal models and human studies. Although the effect of probiotics on allergic responses is different depending on the strains, doses, and experimental protocols, animal studies generally have shown immunomodulatory activities of probiotics including suppression of specific or nonspecific IgE production, reduction of infiltrated eosinophils and degranulated mast cells, potentiation of regulatory T cell cytokines such as IL-10 and TGF-beta relative to IL-4 and IL-5, and potentiation of Th1/Th2 activity along with reduced symptoms of AD. Several well-designed double-blind placebo-controlled human studies showed that some probiotic strains administered during perinatal period prevented the occurrence of AD but could not consistently show a reduction in specific or nonspecific IgE or a change in specific immunomodulatory cytokines. Taken together, published results suggest that the administration of selected strains of probiotics during the perinatal period may be helpful in the prevention of AD.
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PMID:Probiotics in primary prevention of atopic dermatitis. 1936 16

Diet influences the composition of the gut microbiota and host's health, particularly in patients suffering from food-related diseases. Coeliac disease (CD) is a permanent intolerance to cereal gluten proteins and the only therapy for the patients is to adhere to a life-long gluten-free diet (GFD). In the present preliminary study, the effects of a GFD on the composition and immune function of the gut microbiota were analysed in ten healthy subjects (mean age 30.3 years) over 1 month. Faecal microbiota was analysed by fluorescence in situ hybridisation (FISH) and quantitative PCR (qPCR). The ability of faecal bacteria to stimulate cytokine production by peripheral blood mononuclear cells (PBMC) was determined by ELISA. No significant differences in dietary intake were found before and after the GFD except for reductions (P = 0.001) in polysaccharides. Bifidobacterium, Clostridium lituseburense and Faecalibacterium prausnitzii proportions decreased (P = 0.007, P = 0.031 and P = 0.009, respectively) as a result of the GFD analysed by FISH. Bifidobacterium, Lactobacillus and Bifidobacterium longum counts decreased (P = 0.020, P = 0.001 and P = 0.017, respectively), while Enterobacteriaceae and Escherichia coli counts increased (P = 0.005 and P = 0.003) after the GFD assessed by qPCR. TNF-alpha, interferon-gamma, IL-10 and IL-8 production by PBMC stimulated with faecal samples was also reduced (P = 0.021, P = 0.037, P = 0.002 and P = 0.007, respectively) after the diet. Therefore, the GFD led to reductions in beneficial gut bacteria populations and the ability of faecal samples to stimulate the host's immunity. Thus, the GFD may constitute an environmental variable to be considered in treated CD patients for its possible effects on gut health.
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PMID:Effects of a gluten-free diet on gut microbiota and immune function in healthy adult human subjects. 2046 58


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