Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA121653 | ENA |
REPOSITORIES: ENA
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Project description:Probiotic bacteria, specific representatives of bacterial species that are a common part of the human microbiota, are proposed to deliver health benefits to the consumer by modulation of intestinal function via largely unknown molecular mechanisms. To explore in vivo mucosal responses of healthy adults to probiotics, we obtained transcriptomes in an intervention study following a double-blind placebo-controlled cross-over design. In the mucosa of the proximal small intestine of healthy volunteers, probiotic strains from the species Lactobacillus acidophilus, L. casei and L. rhamnosus each induced differential gene regulatory networks and pathways in the human mucosa. Comprehensive analyses revealed that these transcriptional networks regulate major basal mucosal processes, and uncovered remarkable similarity to response profiles obtained for specific bioactive molecules and drugs. This study elucidates how intestinal mucosa of healthy humans perceive different probiotics and provides avenues for rationally designed tests of clinical applications. Keywords: mucosal response of healthy adult humans to lactic acid bacteria This study was set up according to a randomised double-blind cross-over placebo-controlled design. It contains transcriptional profiles from biopsies from 7 healthy individuals after oral intake of three different Lactobacillus species or placebo control. In total, this study includes data from 7 individuals x 4 treatments=28 arrays.
2010-09-08 | E-GEOD-18741 | biostudies-arrayexpress
Project description:Probiotic bacteria, specific representatives of bacterial species that are a common part of the human microbiota, are proposed to deliver health benefits to the consumer by modulation of intestinal function via largely unknown molecular mechanisms. To explore in vivo mucosal responses of healthy adults to probiotics, we obtained transcriptomes in an intervention study following a double-blind placebo-controlled cross-over design. In the mucosa of the proximal small intestine of healthy volunteers, probiotic strains from the species Lactobacillus acidophilus, L. casei and L. rhamnosus each induced differential gene regulatory networks and pathways in the human mucosa. Comprehensive analyses revealed that these transcriptional networks regulate major basal mucosal processes, and uncovered remarkable similarity to response profiles obtained for specific bioactive molecules and drugs. This study elucidates how intestinal mucosa of healthy humans perceive different probiotics and provides avenues for rationally designed tests of clinical applications. Keywords: mucosal response of healthy adult humans to lactic acid bacteria
2010-09-08 | GSE18741 | GEO
Project description:Some commensal bacteria stimulate the immune system but do not present specific antigenicity. Such adjuvant effects have been reported for the bacterial species Lactobacillus plantarum. To study in vivo human responses to L. plantarum, a randomised double-blind placebo-controlled cross-over study was performed. Healthy adults were provided preparations of living and heat-killed L. plantarum bacteria, biopsies were taken from the intestinal mucosa and altered transcriptional profiles were analysed. Transcriptional profiles of human epithelia displayed striking differences upon exposure to living L. plantarum bacteria harvested at different growth phases. Modulation of NF-κB-dependent pathways was central among the major altered cellular responses. This unique in vivo study shows which cellular pathways are associated with the induction of immune tolerance in mucosal tissues towards common adjuvanticity possessing lactobacilli. Keywords: mucosal response of healthy adult humans to lactic acid bacteria This study was set up according to a randomised double-blind cross-over placebo-controlled design. It contains transcriptional profiles from biopsies from 8 healthy individuals after oral intake of three different growth stages of Lactobacillus plantarum or placebo control. In total, this study includes data from 8 individuals x 4 treatments=32 arrays.
2009-01-20 | E-GEOD-11355 | biostudies-arrayexpress
Project description:Some commensal bacteria stimulate the immune system but do not present specific antigenicity. Such adjuvant effects have been reported for the bacterial species Lactobacillus plantarum. To study in vivo human responses to L. plantarum, a randomised double-blind placebo-controlled cross-over study was performed. Healthy adults were provided preparations of living and heat-killed L. plantarum bacteria, biopsies were taken from the intestinal mucosa and altered transcriptional profiles were analysed. Transcriptional profiles of human epithelia displayed striking differences upon exposure to living L. plantarum bacteria harvested at different growth phases. Modulation of NF-κB-dependent pathways was central among the major altered cellular responses. This unique in vivo study shows which cellular pathways are associated with the induction of immune tolerance in mucosal tissues towards common adjuvanticity possessing lactobacilli. Keywords: mucosal response of healthy adult humans to lactic acid bacteria
2009-01-21 | GSE11355 | GEO
Project description:Mucosal responses of healthy humans to exponentially growing or stationary Lactobacillus plantarum bacteria
| PRJNA106573 | ENA
Project description:Background: In the last decade, much attention has been drawn to probiotic bacteria in the context of inflammatory bowel disease (IBD), since the potential of certain strains to attenuate inflammation was demonstrated in several animal experiments and clinical studies. Data in humans elucidating the molecular mechanism of probiotic action are still scarce. To this end, we used an organ culture system of human colon mucosa and investigated the gene expression profiles after treatment with different probiotic bacteria in phorbol 12-myristate 13-acetate (PMA)/ionomycin (IO)) stimulated samples using whole genome microarrays. Moreover, we analyzed changes occurring in the intestinal explants cultured for 8 hours when compared to fresh, directly frozen mucosa, in order to infer the suitability of the system to study an inflammatory stimulus and likely antiinflammatory responses. Results: Culturing intestinal colon fragments during 8 hours elicited differential gene expression in 283 genes, 229 upregulated and 54 downregulated. Upregulated genes were predominantly related to apoptosis, whereas downregulated genes encoded mitochondrial proteins. No specific enrichment of genes related to inflammation or immune response could be detected, confirming the suitability of the system to further study the inmunomodulatory/anti-inflammatory properties of Lactobacillus casei BL23 (BL23), L.plantarum 299v (LP299v) and L.plantarum 299v (A-) (LP299v (A-)), a mutant strain with reduced adhesive properties to enterocytes. Intestinal explants were stimulated with PMA/IO for 3 hours and subsequently incubated with probiotic bacteria for 4 h. ANOVA analysis (p ? 0,01) revealed 205 differentially expressed genes between Control, PMA/IO (Inflamed), and the 3 bacterial treatments. Most importantly, a number of PMA/IO induced genes related to immune response and immune system process such as IL-2, IFN-?, IL17A and pro-inflammatory cytokines CXCL9 and CXCL11 were downregulated by BL23, LP299v and LP299v (A-). The behaviour of the three Lactobacillus strains was quite similar, although their presence induced differential expression of a small number of genes in a strain dependent manner. Conclusion: The human colon organ culture was found to be a suitable model for the study of inflammatory/anti-inflammatory stimuli, and therefore it constitutes a valuable tool to determine the inmunomodulatory effect of probiotic bacteria. The global transcriptional profile evoked by strains BL23, LP299v and LP299v (A-) in artificially inflamed tissue indicated a clear homeostasis restoring effect, including a decrease of the signals produced by activated T cells. Macroscopically healthy colonic intestinal tissue was obtained at surgery from 3 patients. Intestinal explants were treated with PMA and ionomycin for 3 h to induce pro-inflammatory conditions. Then, culture medium was changed and replaced with either medium or medium containing either Lactobacillus casei BL23, Lactobacillus plantarum 299v, or a nonadherent mutant of L. plantarum 299v (A-) and incubated for further 4 hours. In parallel, control intestinal explants were cultured without any treatment of PMA/ionomycin or probiotic bacteria and compared to directly frozen tissue in order to evaluate changes in gene expression which are due solely to the culture conditions.
2012-06-19 | E-GEOD-23630 | biostudies-arrayexpress
Project description:Analysis of human primary macrophages after live Lactobacillus rhamnosus GG (LGG) or LC705 stimulation for 6h and 24h. The results reveal novel mechanisms for probiotics-induced activation of the healthy human innate immune system. Macrophages are phagocytic cells of the innate immune system that perform sentinel functions to initiate appropriate responses to surrounding stimuli. Macrophages that reside at mucosa encounter ingested bacteria. Our understanding of the responses elicited by nonpathogenic bacteria in human innate immune system is limited. Lactobacillus are nonpathogenic bacteria commonly used in food and as supplements with health-promoting probiotic potential. In this study, we have utilized global gene expression profiling to compare the responses of human primary macrophages to two closely related, well-characterized L. rhamnosus strains LGG and LC705. Our results demonstrate that live LGG and LC705 induced quantitatively different gene expression in macrophages. A gene ontology analysis revealed functional similarities and differences in responses to LGG and LC705. Both LGG and LC705 induced IL-1b production in macrophages that required caspase-1 activity. LC705 but not LGG induced a strong type I IFN-dependent gene activation that correlated with the ability of LC705 to prevent influenza A virus replication and production of viral proteins in macrophages. Differentiated 7d human primary macrophages from 18 healthy individuals were stimulated with either live L. rhamnosus GG (LGG) or LC705 for 6 h and 24 h in RPMI medium containing penicillin and streptomycin. As a control, macrophages were stimulated with the medium only. The experiment was performed three times, each time with cells from six different individuals (samples 1-3). For each experiment, macrophages were stimulated separately as described, and macrophages from different donors were pooled after each stimulation experiment. Extracted RNA was hybridized to AffymetrixM-BM-. U133-plus2.0 GeneChipM-BM-. arrays.
2013-03-18 | E-GEOD-20940 | biostudies-arrayexpress
Project description:Analysis of human primary macrophages after live Lactobacillus rhamnosus GG (LGG) or LC705 stimulation for 6h and 24h. The results reveal novel mechanisms for probiotics-induced activation of the healthy human innate immune system. Macrophages are phagocytic cells of the innate immune system that perform sentinel functions to initiate appropriate responses to surrounding stimuli. Macrophages that reside at mucosa encounter ingested bacteria. Our understanding of the responses elicited by nonpathogenic bacteria in human innate immune system is limited. Lactobacillus are nonpathogenic bacteria commonly used in food and as supplements with health-promoting probiotic potential. In this study, we have utilized global gene expression profiling to compare the responses of human primary macrophages to two closely related, well-characterized L. rhamnosus strains LGG and LC705. Our results demonstrate that live LGG and LC705 induced quantitatively different gene expression in macrophages. A gene ontology analysis revealed functional similarities and differences in responses to LGG and LC705. Both LGG and LC705 induced IL-1b production in macrophages that required caspase-1 activity. LC705 but not LGG induced a strong type I IFN-dependent gene activation that correlated with the ability of LC705 to prevent influenza A virus replication and production of viral proteins in macrophages.
2013-03-18 | GSE20940 | GEO
Project description:Numerous studies have shown that resistance to oxidative stress is crucial to stay healthy and to reduce the adverse effects of aging. Accordingly, nutritional interventions using antioxidant food-grade compounds or food products are currently an interesting option to help improve health and quality of life in the elderly. Live lactic acid bacteria (LAB) administered in food, such as probiotics, may be good antioxidant candidates. Nevertheless, information about LAB-induced oxidative stress protection is scarce. To identify and characterize new potential antioxidant probiotic strains, we have developed a new functional screening method using the nematode Caenorhabditis elegans as host. C. elegans were fed on different LAB strains (78 in total) and nematode viability was assessed after oxidative stress (3mM and 5mM H2O2). One strain, identified as Lactobacillus rhamnosus CNCM I-3690, protected worms by increasing their viability by 30% and, also, increased average worm lifespan by 20%. We performed a transcriptomic analysis of C. elegans fed with this strain and showed that increased lifespan is correlated with differential expression of the DAF-16/insulin-like pathway, which is highly conserved in humans. Gene expression in C. elegans wild-type strain (N2) was analyzed in worm populations fed with E. coli OP50 (control condition) or the corresponding LAB (Lactobacillus rhamnosus CNCM I-3690 or Lactobacillus rhamnosus CNCM I-4317) . Three days and ten days feeding period was analyzed.
2012-12-31 | E-GEOD-42192 | biostudies-arrayexpress
Project description:Background: In the last decade, much attention has been drawn to probiotic bacteria in the context of inflammatory bowel disease (IBD), since the potential of certain strains to attenuate inflammation was demonstrated in several animal experiments and clinical studies. Data in humans elucidating the molecular mechanism of probiotic action are still scarce. To this end, we used an organ culture system of human colon mucosa and investigated the gene expression profiles after treatment with different probiotic bacteria in phorbol 12-myristate 13-acetate (PMA)/ionomycin (IO)) stimulated samples using whole genome microarrays. Moreover, we analyzed changes occurring in the intestinal explants cultured for 8 hours when compared to fresh, directly frozen mucosa, in order to infer the suitability of the system to study an inflammatory stimulus and likely antiinflammatory responses. Results: Culturing intestinal colon fragments during 8 hours elicited differential gene expression in 283 genes, 229 upregulated and 54 downregulated. Upregulated genes were predominantly related to apoptosis, whereas downregulated genes encoded mitochondrial proteins. No specific enrichment of genes related to inflammation or immune response could be detected, confirming the suitability of the system to further study the inmunomodulatory/anti-inflammatory properties of Lactobacillus casei BL23 (BL23), L.plantarum 299v (LP299v) and L.plantarum 299v (A-) (LP299v (A-)), a mutant strain with reduced adhesive properties to enterocytes. Intestinal explants were stimulated with PMA/IO for 3 hours and subsequently incubated with probiotic bacteria for 4 h. ANOVA analysis (p ≤ 0,01) revealed 205 differentially expressed genes between Control, PMA/IO (Inflamed), and the 3 bacterial treatments. Most importantly, a number of PMA/IO induced genes related to immune response and immune system process such as IL-2, IFN-γ, IL17A and pro-inflammatory cytokines CXCL9 and CXCL11 were downregulated by BL23, LP299v and LP299v (A-). The behaviour of the three Lactobacillus strains was quite similar, although their presence induced differential expression of a small number of genes in a strain dependent manner. Conclusion: The human colon organ culture was found to be a suitable model for the study of inflammatory/anti-inflammatory stimuli, and therefore it constitutes a valuable tool to determine the inmunomodulatory effect of probiotic bacteria. The global transcriptional profile evoked by strains BL23, LP299v and LP299v (A-) in artificially inflamed tissue indicated a clear homeostasis restoring effect, including a decrease of the signals produced by activated T cells.
2012-06-20 | GSE23630 | GEO