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Frontiers in Immunology 2020is a relatively new genus of bacteria isolated primarily from medical clinical samples, although at a low rate compared to other genus members of the phylum, which are... (Review)
Review
is a relatively new genus of bacteria isolated primarily from medical clinical samples, although at a low rate compared to other genus members of the phylum, which are highly relevant in dysbiosis and disease. According to the taxonomy database at The National Center for Biotechnology Information, the genus consists of 13 species: , and and , and the subspecies subspecies vulgaris (vs. subsp.) are the newest strains featured outside that list. Although typically isolated from the human gut microbiome various species of this genus have been isolated from patients suffering from appendicitis, and abdominal and rectal abscess. It is possible that as spp. emerge, their identification in clinical samples may be underrepresented as novel MS-TOF methods may not be fully capable to discriminate distinct species as separate since it will require the upgrading of MS-TOF identification databases. In terms of pathogenicity, there is contrasting evidence indicating that may have protective effects against some diseases, including liver fibrosis, colitis, cancer immunotherapy, and cardiovascular disease. In contrast, other studies indicate is pathogenic in colorectal cancer and is associated with mental signs of depression. Gut dysbiosis seems to play a role in determining the compositional abundance of in the feces (., in non-alcoholic steatohepatitis, hepatic encephalopathy, and liver fibrosis). Since is a relatively recent sub-branch genus of the phylum, and since are commonly associated with chronic intestinal inflammation, this narrative review illustrates emerging immunological and mechanistic implications by which spp. correlate with human health.
Topics: Animals; Bacteroidetes; Dysbiosis; Gastrointestinal Microbiome; Host-Pathogen Interactions; Humans; Inflammation; Intestines; Mental Disorders; Mental Health; Neoplasms
PubMed: 32582143
DOI: 10.3389/fimmu.2020.00906 -
Cell Host & Microbe Mar 2024Hyperuricemia induces inflammatory arthritis and accelerates the progression of renal and cardiovascular diseases. Gut microbiota has been linked to the development of...
Hyperuricemia induces inflammatory arthritis and accelerates the progression of renal and cardiovascular diseases. Gut microbiota has been linked to the development of hyperuricemia through unclear mechanisms. Here, we show that the abundance and centrality of Alistipes indistinctus are depleted in subjects with hyperuricemia. Integrative metagenomic and metabolomic analysis identified hippuric acid as the key microbial effector that mediates the uric-acid-lowering effect of A. indistinctus. Mechanistically, A. indistinctus-derived hippuric acid enhances the binding of peroxisome-proliferator-activated receptor γ (PPARγ) to the promoter of ATP-binding cassette subfamily G member 2 (ABCG2), which in turn boosts intestinal urate excretion. To facilitate this enhanced excretion, hippuric acid also promotes ABCG2 localization to the brush border membranes in a PDZ-domain-containing 1 (PDZK1)-dependent manner. These findings indicate that A. indistinctus and hippuric acid promote intestinal urate excretion and offer insights into microbiota-host crosstalk in the maintenance of uric acid homeostasis.
Topics: Humans; Hyperuricemia; Uric Acid; Intestines; ATP-Binding Cassette Transporters; Hippurates; Bacteroidetes
PubMed: 38412863
DOI: 10.1016/j.chom.2024.02.001 -
Nature Jan 2014Long-term dietary intake influences the structure and activity of the trillions of microorganisms residing in the human gut, but it remains unclear how rapidly and... (Clinical Trial)
Clinical Trial
Long-term dietary intake influences the structure and activity of the trillions of microorganisms residing in the human gut, but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundance of bile-tolerant microorganisms (Alistipes, Bilophila and Bacteroides) and decreased the levels of Firmicutes that metabolize dietary plant polysaccharides (Roseburia, Eubacterium rectale and Ruminococcus bromii). Microbial activity mirrored differences between herbivorous and carnivorous mammals, reflecting trade-offs between carbohydrate and protein fermentation. Foodborne microbes from both diets transiently colonized the gut, including bacteria, fungi and even viruses. Finally, increases in the abundance and activity of Bilophila wadsworthia on the animal-based diet support a link between dietary fat, bile acids and the outgrowth of microorganisms capable of triggering inflammatory bowel disease. In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles.
Topics: Adult; Bacteria; Bacteroides; Bile Acids and Salts; Bilophila; Carnivory; Diet; Diet, Vegetarian; Dietary Fats; Feces; Female; Fermentation; Food Microbiology; Gastrointestinal Tract; Gene Expression Regulation, Bacterial; Herbivory; Humans; Inflammatory Bowel Diseases; Male; Metagenome; Microbiota; Time Factors; Young Adult
PubMed: 24336217
DOI: 10.1038/nature12820 -
American Journal of Transplantation :... Feb 2023Intestinal commensals can exert immunomodulatory effects on the host, with beneficial or detrimental consequences depending on underlying diseases. We have previously...
Intestinal commensals can exert immunomodulatory effects on the host, with beneficial or detrimental consequences depending on underlying diseases. We have previously correlated longer survival of minor mismatched skin grafts in mice with the presence of an intestinal commensal bacterium, Alistipes onderdonkii. In this study, we investigated its sufficiency and mechanism of action. Oral administration of A onderdonkii strain DSM19147 but not DSM108265 was sufficient to prolong minor mismatched skin graft survival through inhibition of tumor necrosis factor production. Through metabolomic and metagenomic comparisons between DSM19147 and DSM108265, we identified candidate gene products associated with the anti-inflammatory effect of DSM19147. A onderdonkii DSM19147 can lower inflammation both at a steady state and after transplantation and may serve as an anti-inflammatory probiotic beneficial for transplant recipients.
Topics: Animals; Mice; Administration, Oral; Allografts; Graft Rejection; Graft Survival; Mice, Inbred BALB C; Mice, Inbred C57BL; Skin Transplantation; Transplantation, Homologous; Bacteroidetes; Probiotics
PubMed: 36804134
DOI: 10.1016/j.ajt.2022.11.011 -
Cancer Discovery Apr 2022Several approaches to manipulate the gut microbiome for improving the activity of cancer immune-checkpoint inhibitors (ICI) are currently under evaluation. Here, we show...
UNLABELLED
Several approaches to manipulate the gut microbiome for improving the activity of cancer immune-checkpoint inhibitors (ICI) are currently under evaluation. Here, we show that oral supplementation with the polyphenol-rich berry camu-camu (CC; Myrciaria dubia) in mice shifted gut microbial composition, which translated into antitumor activity and a stronger anti-PD-1 response. We identified castalagin, an ellagitannin, as the active compound in CC. Oral administration of castalagin enriched for bacteria associated with efficient immunotherapeutic responses (Ruminococcaceae and Alistipes) and improved the CD8+/FOXP3+CD4+ ratio within the tumor microenvironment. Moreover, castalagin induced metabolic changes, resulting in an increase in taurine-conjugated bile acids. Oral supplementation of castalagin following fecal microbiota transplantation from ICI-refractory patients into mice supported anti-PD-1 activity. Finally, we found that castalagin binds to Ruminococcus bromii and promoted an anticancer response. Altogether, our results identify castalagin as a polyphenol that acts as a prebiotic to circumvent anti-PD-1 resistance.
SIGNIFICANCE
The polyphenol castalagin isolated from a berry has an antitumor effect through direct interactions with commensal bacteria, thus reprogramming the tumor microenvironment. In addition, in preclinical ICI-resistant models, castalagin reestablishes the efficacy of anti-PD-1. Together, these results provide a strong biological rationale to test castalagin as part of a clinical trial. This article is highlighted in the In This Issue feature, p. 873.
Topics: Animals; Bacteria; Fecal Microbiota Transplantation; Gastrointestinal Microbiome; Humans; Mice; Polyphenols
PubMed: 35031549
DOI: 10.1158/2159-8290.CD-21-0808 -
Frontiers in Cellular and Infection... 2023The oral cavity and the gut tract are interconnected, and both contain abundant natural microbiota. Gut microbiota may interact with oral flora and participate in the...
INTRODUCTION
The oral cavity and the gut tract are interconnected, and both contain abundant natural microbiota. Gut microbiota may interact with oral flora and participate in the development of periodontitis. However, the specific role of certain gut microbiota taxa for periodontitis has not been investigated. Mendelian Randomization is an ideal method to explore causal relationships avoiding reverse causality and potential confounding factors. Thus, we conducted a two-sample Mendelian Randomization study to comprehensively reveal the potential genetic causal effect of gut microbiota on periodontitis.
METHODS
SNPs strongly associated with 196 gut microbiota taxa (18,340 individuals) were selected as instrument variables, and periodontitis (17,353 periodontitis cases and 28,210 controls) was used as the outcome. The causal effect was analyzed via random effect inverse variance-weighted, weighted median, and MR-Egger. The sensitivity analyses were conducted using Cochran's Q tests, funnel plots, leave-one-out analyses, and MR-Egger intercept tests.
RESULTS
Nine gut microbiota taxa ( 7, UCG-008, , , , , S24.7 group, , and ) are predicted to play a causal role in enhancing the risk of periodontitis (< 0.05). Besides, two gut microbiota taxa ( and 6) have potentially inhibitive causal effects on the risk of periodontitis (< 0.05). No significant estimation of heterogeneity or pleiotropy is detected.
CONCLUSION
Our study demonstrates the genetic causal effect of 196 gut microbiota taxa on periodontitis and provides guidance for the clinical intervention of periodontitis.
Topics: Humans; Gastrointestinal Microbiome; Mendelian Randomization Analysis; Periodontitis; Microbiota; Bacteroidetes; Clostridiales
PubMed: 37305424
DOI: 10.3389/fcimb.2023.1160993 -
Enfermedades Infecciosas Y... Feb 2023
Topics: Humans; Bacteroidetes; Bacteremia; Peritonitis
PubMed: 36443191
DOI: 10.1016/j.eimce.2022.11.002 -
Nutrients Jun 2022The involvement of the gut microbiota and the metabolites of colon-residing bacteria in brain disease pathogenesis has been covered in a growing number of studies, but... (Review)
Review
The involvement of the gut microbiota and the metabolites of colon-residing bacteria in brain disease pathogenesis has been covered in a growing number of studies, but comparative literature is scarce. To fill this gap, we explored the contribution of the microbiota-gut-brain axis to the pathophysiology of seven brain-related diseases (attention deficit hyperactivity disorder, autism spectrum disorder, schizophrenia, Alzheimer's disease, Parkinson's disease, major depressive disorder, and bipolar disorder). In this article, we discussed changes in bacterial abundance and the metabolic implications of these changes on disease development and progression. Our central findings indicate that, mechanistically, all seven diseases are associated with a leaky gut, neuroinflammation, and over-activated microglial cells, to which gut-residing bacteria and their metabolites are important contributors. Patients show a pro-inflammatory shift in their colon microbiota, harbouring more Gram-negative bacteria containing immune-triggering lipopolysaccharides (LPS) in their cell walls. In addition, bacteria with pro-inflammatory properties (, , ) are found in higher abundances, whereas lower abundances of anti-inflammatory bacteria (, , , , , , , , ) are reported, when compared to healthy controls. On the metabolite level, aberrant levels of short-chain fatty acids (SCFAs) are involved in disease pathogenesis and are mostly found in lower quantities. Moreover, bacterial metabolites such as neurotransmitters (acetylcholine, dopamine, noradrenaline, GABA, glutamate, serotonin) or amino acids (phenylalanine, tryptophan) also play an important role. In the future, defined aberrations in the abundance of bacteria strains and altered bacterial metabolite levels could likely be possible markers for disease diagnostics and follow-ups. Moreover, they could help to identify novel treatment options, underlining the necessity for a deeper understanding of the microbiota-gut-brain axis.
Topics: Alzheimer Disease; Autism Spectrum Disorder; Bacteria; Brain; Depressive Disorder, Major; Dysbiosis; Humans
PubMed: 35807841
DOI: 10.3390/nu14132661 -
International Journal of Systematic and... Jan 2020Three groups of Gram-stain-negative, obligately anaerobic, rod or coccoid-shaped bacteria, which were phylogenetically assigned in the genus belonging to the family in...
Three groups of Gram-stain-negative, obligately anaerobic, rod or coccoid-shaped bacteria, which were phylogenetically assigned in the genus belonging to the family in the phylum , were isolated from the faecal samples of healthy Japanese humans. Group I (strains 5CBH24 and 6CPBBH3) showed highest 16S rRNA gene sequence similarity to '' ph8 (99.73 %). Group II (strain 5CPEGH6) was related to WAL 8301 (96.82 %). Ten strains of group III (3BBH6, 5CPYCFAH4, 5NYCFAH2 and others) were related to DSM 19147 (98.96 %). Group I could be differentiated from other strains by the ability to hydrolyse aesculin and the lack of catalase activity. Strain 5CPEGH6 could be differentiated from JCM 16773 by the inability to hydrolyse aesculin and the lack of catalase activity, and so on. Phenotypic characteristics of group III were similar to those of JCM 16771. Strains 5CBH24, 6CPBBH3 and '' ph8 shared 98.8-98.9 % average nucleotide identity (ANI) with each other. In addition, the DNA-DNA hybridization (DDH) values among three strains were 86.7-89.4 %. Strain 5CPEGH6 showed relatively low values (≤ 84.4 % for ANI ; ≤26.2 % for DDH) with other strains. Three strains in the group III (3BBH6, 5CPYCFAH4 and 5NYCFAH2) shared 97.9-99.9% ANI with each other. These three strains showed 96.9-97.3 % ANI with DSM 19147. The DDH values of strains 3BBH6, 5CPYCFAH4 and 5NYCFAH2 among themselves were 80.5-99.8 %, while those compared to DSM 19147 were 71.0-73.4 %. On the basis of the collected data, three novel species, sp. nov. (5CBH24=JCM 32850=DSM 108979), sp. nov. (5CPEGH6=JCM 32848=DSM 108978) and subsp. subsp. nov. (3BBH6=JCM 32839=DSM 108977), are proposed.
Topics: Bacterial Typing Techniques; Bacteroidetes; Base Composition; DNA, Bacterial; Feces; Humans; Japan; Nucleic Acid Hybridization; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 31633480
DOI: 10.1099/ijsem.0.003778 -
Neurogastroenterology and Motility Aug 2014Depression is a chronic syndrome with a pathogenesis linked to various genetic, biological, and environmental factors. Several links between gut microbiota and...
BACKGROUND
Depression is a chronic syndrome with a pathogenesis linked to various genetic, biological, and environmental factors. Several links between gut microbiota and depression have been established in animal models. In humans, however, few correlations have yet been demonstrated. The aim of our work was therefore to identify potential correlations between human fecal microbiota (as a proxy for gut microbiota) and depression.
METHODS
We analyzed fecal samples from 55 people, 37 patients, and 18 non-depressed controls. Our analyses were based on data generated by Illumina deep sequencing of 16S rRNA gene amplicons.
KEY RESULTS
We found several correlations between depression and fecal microbiota. The correlations, however, showed opposite directions even for closely related Operational Taxonomic Units (OTU's), but were still associated with certain higher order phylogroups. The order Bacteroidales showed an overrepresentation (p = 0.05), while the family Lachnospiraceae showed an underrepresentation (p = 0.02) of OTU's associated with depression. At low taxonomic levels, there was one clade consisting of five OTU's within the genus Oscillibacter, and one clade within Alistipes (consisting of four OTU's) that showed a significant association with depression (p = 0.03 and 0.01, respectively).
CONCLUSIONS & INFERENCES
The Oscillibacter type strain has valeric acid as its main metabolic end product, a homolog of neurotransmitter GABA, while Alistipes has previously been shown to be associated with induced stress in mice. In conclusion, the taxonomic correlations detected here may therefore correspond to mechanistic models.
Topics: Adult; Depressive Disorder; Feces; Female; Humans; Male; Microbiota; Middle Aged; RNA, Ribosomal, 16S
PubMed: 24888394
DOI: 10.1111/nmo.12378