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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 -
Clinical Infectious Diseases : An... Jun 1995
Review
Topics: Gram-Negative Anaerobic Bacteria; Gram-Negative Bacterial Infections; Humans; beta-Lactamases
PubMed: 7548555
DOI: 10.1093/clinids/20.supplement_2.s210 -
Nature Communications Jul 2018Dietary lipids favor the growth of the pathobiont Bilophila wadsworthia, but the relevance of this expansion in metabolic syndrome pathogenesis is poorly understood....
Dietary lipids favor the growth of the pathobiont Bilophila wadsworthia, but the relevance of this expansion in metabolic syndrome pathogenesis is poorly understood. Here, we showed that B. wadsworthia synergizes with high fat diet (HFD) to promote higher inflammation, intestinal barrier dysfunction and bile acid dysmetabolism, leading to higher glucose dysmetabolism and hepatic steatosis. Host-microbiota transcriptomics analysis reveal pathways, particularly butanoate metabolism, which may underlie the metabolic effects mediated by B. wadsworthia. Pharmacological suppression of B. wadsworthia-associated inflammation demonstrate the bacterium's intrinsic capacity to induce a negative impact on glycemic control and hepatic function. Administration of the probiotic Lactobacillus rhamnosus CNCM I-3690 limits B. wadsworthia-induced immune and metabolic impairment by limiting its expansion, reducing inflammation and reinforcing intestinal barrier. Our results suggest a new avenue for interventions against western diet-driven inflammatory and metabolic diseases.
Topics: Animals; Bilophila; Blood Glucose; Cytokines; Desulfovibrionaceae Infections; Diet, High-Fat; Dietary Fats; Fatty Liver; Gastrointestinal Microbiome; Lacticaseibacillus rhamnosus; Liver; Liver Function Tests; Male; Metabolic Networks and Pathways; Metabolic Syndrome; Mice; Mice, Inbred C57BL; Probiotics; Transcriptome
PubMed: 30022049
DOI: 10.1038/s41467-018-05249-7 -
Progress in Molecular Biology and... 2020Although there is associative evidence linking fecal microbiome profile to health and disease, many studies have not considered the confounding effects of dietary... (Review)
Review
Although there is associative evidence linking fecal microbiome profile to health and disease, many studies have not considered the confounding effects of dietary intake. Consuming food provides fermentable substrate which sustains the microbial ecosystem that resides with most abundance in the colon. Western, Mediterranean and vegetarian dietary patterns have a role in modulating the gut microbiota, as do trending restrictive diets such the paleolithic and ketogenic. Altering the amount or ratio of carbohydrate, protein and fat, particularly at the extremes of intake, impacts the microbiome. Diets high in fermentable carbohydrates support the relative abundance of Bifidobacterium, Prevotella, Ruminococcus, Dorea and Roseburia, among others, capable of degrading polysaccharides, oligosaccharides and sugars. Conversely, very high fat diets increase bile-resistant organisms such as Bilophila and Bacteroides. Food form, whole foods vs. ultra-processed, alters the provision of macronutrient substrate to the colon due to differing digestibility, and thereby may impact the microbiota and its metabolic activity. In addition, phytochemicals in plant-based foods have specific and possibly prebiotic effects on the microbiome. Further, food ingredients such as certain low-calorie sweeteners enhance Bifidobacterium spp. The weight of evidence to date suggests a high level of interindividual variability in the human microbiome vs. clearly defined, dietary-induced profiles. Healthful dietary patterns, emphasizing plant foods high in microbial-available carbohydrate, support favorable microbiome profiles active in saccharolytic fermentation. Future research into diet and microbiome should consider the balance of gut microbial-generated metabolites, an important link between microbiome profile and human health.
Topics: Diet; Humans; Microbiota; Nutrients
PubMed: 32475524
DOI: 10.1016/bs.pmbts.2020.04.006 -
Cell Host & Microbe Sep 2021Many genetic and environmental factors increase susceptibility to cognitive impairment (CI), and the gut microbiome is increasingly implicated. However, the identity of...
Many genetic and environmental factors increase susceptibility to cognitive impairment (CI), and the gut microbiome is increasingly implicated. However, the identity of gut microbes associated with CI risk, their effects on CI, and their mechanisms remain unclear. Here, we show that a carbohydrate-restricted (ketogenic) diet potentiates CI induced by intermittent hypoxia in mice and alters the gut microbiota. Depleting the microbiome reduces CI, whereas transplantation of the risk-associated microbiome or monocolonization with Bilophila wadsworthia confers CI in mice fed a standard diet. B. wadsworthia and the risk-associated microbiome disrupt hippocampal synaptic plasticity, neurogenesis, and gene expression. The CI is associated with microbiome-dependent increases in intestinal interferon-gamma (IFNg)-producing Th1 cells. Inhibiting Th1 cell development abrogates the adverse effects of both B. wadsworthia and environmental risk factors on CI. Together, these findings identify select gut bacteria that contribute to environmental risk for CI in mice by promoting inflammation and hippocampal dysfunction.
Topics: Animals; Bilophila; Cognitive Dysfunction; Diet, Ketogenic; Gastrointestinal Microbiome; Hippocampus; Hypoxia, Brain; Interferon-gamma; Mice; Mice, Inbred C57BL; Mice, Knockout; Th1 Cells
PubMed: 34358434
DOI: 10.1016/j.chom.2021.07.004 -
Frontiers in Immunology 2021Several studies have reported alterations in gut microbiota composition of Alzheimer's disease (AD) patients. However, the observed differences are not consistent across...
INTRODUCTION
Several studies have reported alterations in gut microbiota composition of Alzheimer's disease (AD) patients. However, the observed differences are not consistent across studies. We aimed to investigate associations between gut microbiota composition and AD biomarkers using machine learning models in patients with AD dementia, mild cognitive impairment (MCI) and subjective cognitive decline (SCD).
MATERIALS AND METHODS
We included 170 patients from the Amsterdam Dementia Cohort, comprising 33 with AD dementia (66 ± 8 years, 46%F, mini-mental state examination (MMSE) 21[19-24]), 21 with MCI (64 ± 8 years, 43%F, MMSE 27[25-29]) and 116 with SCD (62 ± 8 years, 44%F, MMSE 29[28-30]). Fecal samples were collected and gut microbiome composition was determined using 16S rRNA sequencing. Biomarkers of AD included cerebrospinal fluid (CSF) amyloid-beta 1-42 (amyloid) and phosphorylated tau (p-tau), and MRI visual scores (medial temporal atrophy, global cortical atrophy, white matter hyperintensities). Associations between gut microbiota composition and dichotomized AD biomarkers were assessed with machine learning classification models. The two models with the highest area under the curve (AUC) were selected for logistic regression, to assess associations between the 20 best predicting microbes and the outcome measures from these machine learning models while adjusting for age, sex, BMI, diabetes, medication use, and MMSE.
RESULTS
The machine learning prediction for amyloid and p-tau from microbiota composition performed best with AUCs of 0.64 and 0.63. Highest ranked microbes included several short chain fatty acid (SCFA)-producing species. Higher abundance of and lower abundance of group spp., spp., spp., spp., spp., , and spp., was associated with higher odds of amyloid positivity. We found associations between lower abundance of spp., spp., and and higher odds of positive p-tau status.
CONCLUSIONS
Gut microbiota composition was associated with amyloid and p-tau status. We extend on recent studies that observed associations between SCFA levels and AD CSF biomarkers by showing that lower abundances of SCFA-producing microbes were associated with higher odds of positive amyloid and p-tau status.
Topics: Aged; Alzheimer Disease; Biomarkers; Brain-Gut Axis; Cognitive Dysfunction; Comorbidity; Dementia; Disease Susceptibility; Female; Gastrointestinal Microbiome; Humans; Machine Learning; Male; Middle Aged; Risk Factors
PubMed: 35173707
DOI: 10.3389/fimmu.2021.794519 -
European Journal of Clinical... Nov 1992Bilophila wadsworthia is an anaerobic, gram-negative, asaccharolytic, urease-positive, bile-resistant, catalase-positive bacillus, originally recovered from infections... (Review)
Review
Bilophila wadsworthia is an anaerobic, gram-negative, asaccharolytic, urease-positive, bile-resistant, catalase-positive bacillus, originally recovered from infections in patients with gangrenous and perforated appendicitis. Additional isolations from clinical specimens, including pleural fluid, joint fluid, blood and pus from a scrotal abscess, mandibular osteomyelitis and axillary hidradenitis suppurativa are described here. Bilophila is found as normal flora in feces and, occasionally, in saliva and in the vagina. Isolates from humans are usually beta-lactamase positive and therefore resistant to certain beta-lactam antibiotics. Two percent of strains are also resistant to clindamycin.
Topics: Adult; Aged; Drug Resistance, Microbial; Female; Gram-Negative Anaerobic Bacteria; Gram-Negative Bacterial Infections; Humans; Male; Middle Aged
PubMed: 1295759
DOI: 10.1007/BF01967799 -
Journal of Clinical Microbiology Jul 1992Bilophila wadsworthia is an anaerobic, gram-negative, asaccharolytic, bile-resistant, catalase-positive bacillus that is usually urease positive and was originally...
Bilophila wadsworthia is an anaerobic, gram-negative, asaccharolytic, bile-resistant, catalase-positive bacillus that is usually urease positive and was originally recognized in specimens of peritoneal fluid and tissue from patients with appendicitis. Additional isolations from clinical specimens, including a scrotal abscess, mandibular osteomyelitis, axillary hidradenitis suppurativa, pleural fluid, joint fluid, and blood, are described here.
Topics: Adult; Aged; Aged, 80 and over; Child; Female; Gram-Negative Anaerobic Bacteria; Humans; Male; Middle Aged
PubMed: 1629348
DOI: 10.1128/jcm.30.7.1882-1884.1992 -
Nature Jul 2012The composite human microbiome of Western populations has probably changed over the past century, brought on by new environmental triggers that often have a negative...
The composite human microbiome of Western populations has probably changed over the past century, brought on by new environmental triggers that often have a negative impact on human health. Here we show that consumption of a diet high in saturated (milk-derived) fat, but not polyunsaturated (safflower oil) fat, changes the conditions for microbial assemblage and promotes the expansion of a low-abundance, sulphite-reducing pathobiont, Bilophila wadsworthia. This was associated with a pro-inflammatory T helper type 1 (T(H)1) immune response and increased incidence of colitis in genetically susceptible Il10(−/−), but not wild-type mice. These effects are mediated by milk-derived-fat-promoted taurine conjugation of hepatic bile acids, which increases the availability of organic sulphur used by sulphite-reducing microorganisms like B. wadsworthia. When mice were fed a low-fat diet supplemented with taurocholic acid, but not with glycocholic acid, for example, a bloom of B. wadsworthia and development of colitis were observed in Il10(−/−) mice. Together these data show that dietary fats, by promoting changes in host bile acid composition, can markedly alter conditions for gut microbial assemblage, resulting in dysbiosis that can perturb immune homeostasis. The data provide a plausible mechanistic basis by which Western-type diets high in certain saturated fats might increase the prevalence of complex immune-mediated diseases like inflammatory bowel disease in genetically susceptible hosts.
Topics: Animals; Bile Acids and Salts; Bilophila; Colitis; Diet, Fat-Restricted; Dietary Fats; Inflammation; Inflammatory Bowel Diseases; Interleukin-10; Metagenome; Mice; Mice, Inbred C57BL; Milk; Molecular Sequence Data; Safflower Oil; Sulfites; Taurine; Taurocholic Acid; Th1 Cells
PubMed: 22722865
DOI: 10.1038/nature11225 -
Disease Markers 2022To systematically evaluate the differences in intestinal flora before and after menopause. To provide a possible mechanism for perimenopausal syndrome and provide a... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To systematically evaluate the differences in intestinal flora before and after menopause. To provide a possible mechanism for perimenopausal syndrome and provide a basis for probiotics as adjuvant therapy.
METHODS
MEDLINE, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), CNKI, Wanfang, and VIP databases were searched. The included studies were case-control studies.
RESULTS
Three case-control studies were included, with a total of 156 people. At the phylum level, there were no differences between premenopausal and postmenopausal women. At the genus level, the relative abundances of A. odoratum and B. cholerae were higher in postmenopausal women than in premenopausal women, with no differences among other genera. The Shannon diversity index increased after menopause, but no differences were found. Only one study found a positive association of estradiol with Gammaproteobacteria and Myxococcales and a negative association with Prevotellaceae.
CONCLUSIONS
On the basis of previous studies, it was found that there was no significant difference at the phylum level between postmenopausal women and premenopausal women, but Odoribacter and Bilophila increased at the genus level in postmenopausal women. The class of Gammaproteobacteria may be positively correlated with estradiol. Limited by the number of included studies, more high-quality clinical studies are needed for validation.
Topics: Estradiol; Female; Gastrointestinal Microbiome; Humans; Menopause; Postmenopause; Premenopause
PubMed: 35923245
DOI: 10.1155/2022/3767373