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Microorganisms Jul 2021In our previous study the enrichment of the intestinal proteome of type 1 diabetes (T1D) children with proteins was observed, which led us to our current study that...
In our previous study the enrichment of the intestinal proteome of type 1 diabetes (T1D) children with proteins was observed, which led us to our current study that aimed to isolate and characterize species from fecal samples of T1D and control children. Repetitive sequence-based PCR (rep-PCR) was used for typing the isolated species. The antibiotic susceptibility and mucinolytic activity of the isolates was determined. The quantification of specific bacterial groups in the fecal samples was determined by qPCR. The ability to adhere and invade the human colonic cell line HT29-MTX-E12 of strains of , and was determined and their whole genome sequencing was performed. The results showed similar numbers of species in T1D and control samples, but unique species and a higher recovery of from T1D samples was observed. Rep-PCR grouped the different species, but no discrimination by origin was achieved. T1D children showed a significant increase in and a depletion in sp. All tested , and were able to adhere to HT29-MTX-E12 cells but significant differences ( < 0.05) in the ability to invade was observed. The highest ability to invade was exhibited by PtF D14MH1 and PtFD16P1, while strains were unable to invade. The damage to tight junctions was also observed. The presence of sp. inhibited the invasion ability of PtF D14MH1 but not PtFD16P1. Sequences of agonist peptides of the human natural preproinsulin and the insulin B chain insB:9-23 peptide mimics were identified. The results reported in our study stresses the continued efforts required to clarify the link between T1D and gut microbiota.
PubMed: 34361871
DOI: 10.3390/microorganisms9071436 -
Scientific Reports Aug 2023Gut microbiota metabolites have been mechanistically linked to inflammatory pathway activation and atherosclerosis, which are major causes of vascular stiffness (VS)....
Gut microbiota metabolites have been mechanistically linked to inflammatory pathway activation and atherosclerosis, which are major causes of vascular stiffness (VS). Aiming to investigate if the gut microbiome might be involved in VS development, we performed a cross-sectional study (n = 3,087), nested within the population-based European Prospective Investigations into Cancer and Nutrition (EPIC) Potsdam. We investigated the correlation of the gut microbiota (alpha diversity and taxa abundance) with 3 vascular stiffness measures: carotid-femoral (PWV), aortic augmentation index (AIX) and ankle-brachial index (ABI). Shannon index was not significantly associated with VS but the number of observed Amplicon Sequence Variants (ASV) was positively associated with PWV and AIX. We found a total of 19 ASVs significantly associated with at least one VS measure in multivariable-adjusted models. One ASV (classified as Sutterella wadsworthensis) was associated with 2 VS measures, AIX (- 0.11 ± 0.04) and PWV (-0.14 ± 0.03). Other examples of ASVs associated with VS were Collinsella aerofaciens, previously reported to be affected by diet and Bacteroides uniformis, commercially available as probiotics. In conclusion, our study suggests a potential role of individual components of the gut microbiota in the aetiology of VS.
Topics: Humans; Gastrointestinal Microbiome; Cross-Sectional Studies; Prospective Studies; Vascular Stiffness; Cancer Vaccines
PubMed: 37587126
DOI: 10.1038/s41598-023-40178-6 -
Frontiers in Immunology 2022The consumption of plant-based bioactive compounds modulates the gut microbiota and interacts with the innate and adaptive immune responses associated with metabolic...
Cranberry polyphenols and agave agavins impact gut immune response and microbiota composition while improving gut barrier function, inflammation, and glucose metabolism in mice fed an obesogenic diet.
The consumption of plant-based bioactive compounds modulates the gut microbiota and interacts with the innate and adaptive immune responses associated with metabolic disorders. The present study aimed to evaluate the effect of cranberry polyphenols (CP), rich in flavonoids, and agavins (AG), a highly branched agave-derived neo-fructans, on cardiometabolic response, gut microbiota composition, metabolic endotoxemia, and mucosal immunomodulation of C57BL6 male mice fed an obesogenic high-fat and high-sucrose (HFHS) diet for 9 weeks. Interestingly, CP+AG-fed mice had improved glucose homeostasis. Oral supplementation with CP selectively and robustly (five-fold) increases the relative abundance of , a beneficial bacteria associated with metabolic health. AG, either alone or combined with CP (CP+AG), mainly stimulated the glycan-degrading bacteria , , , and This increase of glycan-degrading bacteria was consistent with a significantly increased level of butyrate in obese mice receiving AG, as compared to untreated counterparts. CP+AG-supplemented HFHS-fed mice had significantly lower levels of plasma LBP than HFHS-fed controls, suggesting blunted metabolic endotoxemia and improved intestinal barrier function. Gut microbiota and derived metabolites interact with the immunological factors to improve intestinal epithelium barrier function. Oral administration of CP and AG to obese mice contributed to dampen the pro-inflammatory immune response through different signaling pathways. CP and AG, alone or combined, increased toll-like receptor (TLR)-2 () expression, while decreasing the expression of interleukin 1ß (ILß1) in obese mice. Moreover, AG selectively promoted the anti-inflammatory marker , while CP increased the expression of NOD-like receptor family pyrin domain containing 6 () inflammasome. The intestinal immune system was also shaped by dietary factor recognition. Indeed, the combination of CP+AG significantly increased the expression of aryl hydrocarbon receptors (). Altogether, both CP and AG can shape gut microbiota composition and regulate key mucosal markers involved in the repair of epithelial barrier integrity, thereby attenuating obesity-associated gut dysbiosis and metabolic inflammation and improving glucose homeostasis.
Topics: Agave; Animals; Diet, High-Fat; Endotoxemia; Glucose; Immunity; Inflammation; Mice; Mice, Inbred C57BL; Mice, Obese; Microbiota; Plant Extracts; Polyphenols; Vaccinium macrocarpon
PubMed: 36052065
DOI: 10.3389/fimmu.2022.871080 -
International Journal of Molecular... Sep 2023Previous studies have demonstrated that the intestinal abundance of is significantly higher in healthy controls than that in patients with ulcerative colitis (UC)....
Previous studies have demonstrated that the intestinal abundance of is significantly higher in healthy controls than that in patients with ulcerative colitis (UC). However, what effect has on the development of UC has not been characterized. Here, we show for the first time that F18-22, an alginate-fermenting bacterium isolated from the healthy human colon, protects against dextran-sulfate-sodium (DSS)-induced UC in mice. Specifically, oral intake of F18-22 alleviated colon contraction, improved intestinal bleeding and attenuated mucosal damage in diseased mice. Additionally, F18-22 improved gut dysbiosis in UC mice by increasing the abundance of anti-inflammatory acetate-producing bacterium and decreasing the amount of pro-inflammatory pathogenetic bacteria spp. Moreover, F18-22 was well-tolerated in mice and showed no oral toxicity after repeated daily administration for 28 consecutive days. Taken together, our study illustrates that F18-22 is a safe and novel probiotic bacterium for the treatment of UC from the healthy human colon.
Topics: Humans; Animals; Mice; Colitis, Ulcerative; Colon; Bacteroides; Probiotics; Dextran Sulfate; Disease Models, Animal; Mice, Inbred C57BL; Colitis
PubMed: 37834117
DOI: 10.3390/ijms241914669 -
Archives of Microbiology Aug 2022Two bacterial strains, KH365_2 and KH569_7, were isolated from the cecum contents of wild-derived house mice. The strains were characterized as Gram-negative,...
Two bacterial strains, KH365_2 and KH569_7, were isolated from the cecum contents of wild-derived house mice. The strains were characterized as Gram-negative, rod-shaped, strictly anaerobic, and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences revealed that both strains were most closely related to Bacteroides uniformis ATCC 8492. Whole genome sequences of KH365_2 and KH569_7 strains have a DNA G + C content of 46.02% and 46.03% mol, respectively. Most morphological and biochemical characteristics did not differ between the newly isolated strains and classified Bacteroides strains. However, the average nucleotide identity (ANI) and dDNA-DNA hybridization (dDDH) values clearly distinguished the two strains from described members of the genus Bacteroides. Here, we present the phylogeny, morphology, and physiology of a novel species of the genus Bacteroides and propose the name Bacteroides muris sp. nov., with KH365_2 (DSM 114231 = CCUG 76277) as type strain.
Topics: Animals; Bacterial Typing Techniques; Bacteroides; Cecum; DNA, Bacterial; Fatty Acids; Gastropoda; Mice; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 35939214
DOI: 10.1007/s00203-022-03148-6 -
Gut Microbes Nov 2020glucans are the dietary nutrients present in oats, barley, algae, and mushrooms. The macromolecules are well known for their immune-modulatory activity; however, how the...
glucans are the dietary nutrients present in oats, barley, algae, and mushrooms. The macromolecules are well known for their immune-modulatory activity; however, how the human gut bacteria digest them is vaguely understood. In this study, JCM 13288 was found to grow on laminarin, pustulan, and porphyran. We sequenced the genome of the strain, which was about 5.05 megabase pairs and contained 4868 protein-coding genes. On the basis of growth patterns of the bacterium, two putative polysaccharide utilization loci for glucans were identified from the genome, and associated four putative genes were cloned, expressed, purified, and characterized. Three glycoside hydrolases (GHs) that were endo-acting enzymes (GH16, GH30, and GH158), and one which was an exo-acting (GH3) enzyme. The GH3, GH16, and GH158 can cleave linear exo/endo- 1-3 linkages while GH30 can digest endo- 1-6 linkages. GH30 and GH158 were further explored for their roles in digesting glucans and generation of oligosaccharides, respectively. The GH30 predominately found to cleave long chain 1-6 linked glucans, and obtained final product was gentiobiose. The GH158 used for producing oligosaccharides varying from degree of polymerization 2 to 7 from soluble curdlan. We demonstrated that these oligosaccharides can be utilized by gut bacteria, which either did not grow or poorly grew on laminarin. Thus, JCM 13288 is not only capable of utilizing glucans but also shares these glycans with human gut bacteria for potentially maintaining the gut microbial homeostasis.
Topics: Bacteroides; Carbohydrate Conformation; Gastrointestinal Microbiome; Genetic Loci; Genome, Bacterial; Glycoside Hydrolases; Gram-Positive Bacteria; Microbial Interactions; Oligosaccharides; Polysaccharides; beta-Glucans
PubMed: 33043794
DOI: 10.1080/19490976.2020.1826761 -
MSystems Apr 2023Human gut dysbiosis is associated with type 2 diabetes mellitus (T2DM); however, the gut microbiome in pregnant women with pregestational type 2 diabetes mellitus (PGDM)...
Human gut dysbiosis is associated with type 2 diabetes mellitus (T2DM); however, the gut microbiome in pregnant women with pregestational type 2 diabetes mellitus (PGDM) remains unexplored. We investigated the alterations in the gut microbiota composition in pregnant women with or without PGDM. The gut microbiota was examined using 16S rRNA sequencing data of 234 maternal fecal samples that were collected during the first (T1), second (T2), and third (T3) trimesters. The PGDM group presented a reduction in the number of gut bacteria taxonomies as the pregnancies progressed. Linear discriminant analyses revealed that , , and Roseburia intestinalis were enriched in the PGDM group, whereas Bacteroides vulgatus, Faecalibacterium prausnitzii, Eubacterium rectale, Bacteroides uniformis, Eubacterium eligens, , Bacteroides fragilis, , , R-7, Roseburia inulinivorans, Streptococcus oralis, Prevotella melaninogenica, Neisseria perflava, Bacteroides ovatus, Bacteroides caccae, Veillonella dispar, and Haemophilus parainfluenzae were overrepresented in the control group. Correlation analyses showed that the PGDM-enriched taxa were correlated with higher blood glucose levels during pregnancy, whereas the taxonomic biomarkers of normoglycemic pregnancies exhibited negative correlations with glycemic traits. The microbial networks in the PGDM group comprised weaker microbial interactions than those in the control group. Our study reveals the distinct characteristics of the gut microbiota composition based on gestational ages between normoglycemic and PGDM pregnancies. Further longitudinal research involving women with T2DM at preconception stages and investigations using shotgun metagenomic sequencing should be performed to elucidate the relationships between specific bacterial functions and PGDM metabolic statuses during pregnancy and to identify potential therapeutic targets. The incidence of pregestational type 2 diabetes mellitus (PGDM) is increasing, with high rates of serious adverse maternal and neonatal outcomes that are strongly correlated with hyperglycemia. Recent studies have shown that type 2 diabetes mellitus is associated with gut microbial dysbiosis; however, the gut microbiome composition and its associations with the metabolic features of patients with PGDM remain largely unknown. In this study, we investigated the changes in the gut microbiota composition in pregnant women with and without PGDM. We identified differential taxa that may be correlated with maternal metabolic statuses during pregnancy. Additionally, we observed that the number of taxonomic and microbial networks of gut bacteria were distinctly reduced in women with hyperglycemia as their pregnancies progressed. These results extend our understanding of the associations between the gut microbial composition, PGDM-related metabolic changes, and pregnancy outcomes.
Topics: Infant, Newborn; Humans; Female; Pregnancy; Gastrointestinal Microbiome; Diabetes Mellitus, Type 2; Pregnant Women; Dysbiosis; RNA, Ribosomal, 16S; Pregnancy Outcome; Hyperglycemia
PubMed: 36853013
DOI: 10.1128/msystems.01146-22 -
The Journal of Biological Chemistry Nov 2018The glycoside hydrolases encoded by the human gut microbiome play an integral role in processing a variety of exogenous and endogenous glycoconjugates. Here we present...
The glycoside hydrolases encoded by the human gut microbiome play an integral role in processing a variety of exogenous and endogenous glycoconjugates. Here we present three structurally and functionally distinct β-glucuronidase (GUS) glycoside hydrolases from a single human gut commensal microbe, We show using nine crystal structures, biochemical, and biophysical data that whereas these three proteins share similar overall folds, they exhibit different structural features that create three structurally and functionally unique enzyme active sites. Notably, quaternary structure plays an important role in creating distinct active site features that are hard to predict via structural modeling methods. The enzymes display differential processing capabilities toward glucuronic acid-containing polysaccharides and SN-38-glucuronide, a metabolite of the cancer drug irinotecan. We also demonstrate that GUS-specific and nonselective inhibitors exhibit varying potencies toward each enzyme. Together, these data highlight the diversity of GUS enzymes within a single gut commensal and advance our understanding of how structural details impact the specific roles microbial enzymes play in processing drug-glucuronide and glycan substrates.
Topics: Amino Acid Sequence; Bacteroides; Catalytic Domain; Enzyme Inhibitors; Gastrointestinal Microbiome; Glucaric Acid; Glucuronidase; Humans; Isoenzymes; Protein Conformation
PubMed: 30301767
DOI: 10.1074/jbc.RA118.005414 -
Frontiers in Microbiology 2023Osteoarthritis (OA) is a kind of chronic, degenerative disorder with unknown causes. In this study, we aimed to improve our understanding of the gut microbiota profile...
INTRODUCTION
Osteoarthritis (OA) is a kind of chronic, degenerative disorder with unknown causes. In this study, we aimed to improve our understanding of the gut microbiota profile in patients with knee OA.
METHODS
16S rDNA gene sequencing was performed to detect the gut microbiota in fecal samples collected from the patients with OA ( = 32) and normal control (NC, = 57). Then the metagenomic sequencing was used to identify the genes or functions linked with gut microbial changes at the species level in the fecal samples from patients with OA and NC groups.
RESULTS
The Proteobacteria was identified as dominant bacteria in OA group. We identified 81 genera resulted significantly different in abundance between OA and NC. The abundance of , , , , and showed significant decrease in the OA compared to the NC. The abundance of genera , , and were increasing in the OA group, and the families , , and were increasing in the NC. The metagenomic sequencing showed that the abundance of , and at the species level were significantly decreasing in the OA, and the abundance of , , and were significantly increased in OA.
DISCUSSION
The results of our study interpret a comprehensive profile of the gut microbiota in patients with knee OA and offer the evidence that the cartilage-gut-microbiome axis could play a crucial role in underlying the mechanisms and pathogenesis of OA.
PubMed: 37250055
DOI: 10.3389/fmicb.2023.1153424 -
BMC Pediatrics Oct 2023Sepsis is a life-threatening multiple-organ injury caused by disordered host immune response to microbial infection. However, the correlation between gut microbiota...
Sepsis is a life-threatening multiple-organ injury caused by disordered host immune response to microbial infection. However, the correlation between gut microbiota dysbiosis and immune indicators remains unexplored. To address this gap in knowledge, we carried out 16 S rDNA sequencing, analyzed clinical fecal samples from children with sepsis (n = 30) and control children (n = 25), and obtained immune indicators, including T cell subtypes (CD3, CD3CD4, CD3CD8, and CD4/CD8), NK cells, cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ), and immunoglobulin indices (IgA, IgE, IgM and IgG). In addition, we analyzed the correlation between gut microbiota dysbiosis and immune indicators, and evaluated the clinical discriminatory power of discovered bacterial biomarkers. We found that children with sepsis exhibited gut bacterial dysbiosis and low alpha diversity. The Spearman's rank correlation coefficient suggested that Rhodococcus erythropolis had a significantly positive correlation with IFN-γ and CD3 T cells. Klebsiella pneumoniae and Streptococcus mitis were significantly correlated with NK cells. Bacteroides uniformis was significantly positively correlated with IgM and erythrocyte sedimentation rate, and Eubacterium eligens was significantly positively correlated with IL-4 and CD3CD8 T cells. The biomarkers discovered in this study had strong discriminatory power. These changes in the gut microbiome may be closely related to immunologic dysfunction and to the development or exacerbation of sepsis. However, a large sample size is required for verification.
Topics: Humans; Child; Gastrointestinal Microbiome; CD8-Positive T-Lymphocytes; Dysbiosis; Interleukin-4; Sepsis; Bacteria; Biomarkers; Immunoglobulin M
PubMed: 37845615
DOI: 10.1186/s12887-023-04349-8