The Microbiota-Gut-Brain Axis

Physiological Reviews, Journal Year: 2019, Volume and Issue: 99(4), P. 1877 - 2013

Published: Aug. 28, 2019

The importance of the gut-brain axis in maintaining homeostasis has long been appreciated. However, past 15 yr have seen emergence microbiota (the trillions microorganisms within and on our bodies) as one key regulators function led to appreciation a distinct microbiota-gut-brain axis. This is gaining ever more traction fields investigating biological physiological basis psychiatric, neurodevelopmental, age-related, neurodegenerative disorders. brain communicate with each other via various routes including immune system, tryptophan metabolism, vagus nerve enteric nervous involving microbial metabolites such short-chain fatty acids, branched chain amino peptidoglycans. Many factors can influence composition early life, infection, mode birth delivery, use antibiotic medications, nature nutritional provision, environmental stressors, host genetics. At extreme diversity diminishes aging. Stress, particular, significantly impact at all stages life. Much recent work implicated gut many conditions autism, anxiety, obesity, schizophrenia, Parkinson’s disease, Alzheimer’s disease. Animal models paramount linking regulation fundamental neural processes, neurogenesis myelination, microbiome activation microglia. Moreover, translational human studies are ongoing will greatly enhance field. Future focus understanding mechanisms underlying attempt elucidate microbial-based intervention therapeutic strategies for neuropsychiatric

Language: Английский

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Short Chain Fatty Acids (SCFAs)-Mediated Gut Epithelial and Immune Regulation and Its Relevance for Inflammatory Bowel Diseases

Frontiers in Immunology, Journal Year: 2019, Volume and Issue: 10

Published: March 11, 2019

Ulcerative colitis (UC) and Crohn's disease (CD), collectively known as Inflammatory Bowel Diseases (IBD), are caused by a complex interplay between genetic, immunologic, microbial environmental factors. Dysbiosis of the gut microbiome is increasingly considered to be causatively related IBD strongly affected components Western life style. Bacteria that ferment fibers produce short chain fatty acids (SCFAs) typically reduced in mucosa feces patients with IBD, compared healthy individuals. SCFAs, such acetate, propionate butyrate, important metabolites maintaining intestinal homeostasis. Several studies have indeed shown fecal SCFAs levels active IBD. an fuel for epithelial cells strengthen barrier function. Recent findings, however, show particular also immunomodulatory functions. Absorption facilitated substrate transporters like MCT1 SMCT1 promote cellular metabolism. Moreover, may signal through cell surface G-protein coupled receptors (GPCRs), GPR41, GPR43, GPR109A, activate signaling cascades control immune Transgenic mouse models support key role these GPCRs controlling inflammation. Here, we present overview production their effects on specific emphasis relevance discuss therapeutic potential either applied directly or stimulating SCFAs-producing bacteria pre- probiotic approaches.

Language: Английский

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Introduction to the human gut microbiota

Biochemical Journal, Journal Year: 2017, Volume and Issue: 474(11), P. 1823 - 1836

Published: May 16, 2017

The human gastrointestinal (GI) tract harbours a complex and dynamic population of microorganisms, the gut microbiota, which exert marked influence on host during homeostasis disease. Multiple factors contribute to establishment microbiota infancy. Diet is considered as one main drivers in shaping across life time. Intestinal bacteria play crucial role maintaining immune metabolic protecting against pathogens. Altered bacterial composition (dysbiosis) has been associated with pathogenesis many inflammatory diseases infections. interpretation these studies relies better understanding inter-individual variations, heterogeneity communities along GI tract, functional redundancy need distinguish cause from effect states dysbiosis. This review summarises our current development its impact integrity health, underlying for mechanistic focusing host–microbe interactions.

Language: Английский

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Intestinal Short Chain Fatty Acids and their Link with Diet and Human Health

Frontiers in Microbiology, Journal Year: 2016, Volume and Issue: 7

Published: Feb. 17, 2016

The colon is inhabited by a dense population of microorganisms, the so-called "gut microbiota," able to ferment carbohydrates and proteins that escape absorption in small intestine during digestion. This microbiota produces wide range metabolites, including short chain fatty acids (SCFA). These compounds are absorbed large bowel defined as 1-6 carbon volatile which can present straight or branched-chain conformation. Their production influenced pattern food intake diet-mediated changes gut microbiota. SCFA have distinct physiological effects: they contribute shaping environment, influence physiology colon, be used energy sources host cells intestinal also participate different host-signaling mechanisms. We summarize current knowledge about SCFA, bacterial cross-feedings interactions, biological properties these metabolites with impact on human health.

Language: Английский

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The Firmicutes/Bacteroidetes Ratio: A Relevant Marker of Gut Dysbiosis in Obese Patients?

Nutrients, Journal Year: 2020, Volume and Issue: 12(5), P. 1474 - 1474

Published: May 19, 2020

The gut microbiota is emerging as a promising target for the management or prevention of inflammatory and metabolic disorders in humans. Many current research efforts are focused on identification specific microbial signatures, more particularly those associated with obesity, type 2 diabetes, cardiovascular diseases. Some studies have described that obese animals humans exhibits higher Firmicutes/Bacteroidetes ratio compared normal-weight individuals, proposing this an eventual biomarker. Accordingly, frequently cited scientific literature hallmark obesity. aim present review was to discuss validity potential marker, based great amount contradictory results reported literature. Such discrepancies might be explained by existence interpretative bias generated methodological differences sample processing DNA sequence analysis, generally poor characterization recruited subjects and, particularly, lack consideration lifestyle-associated factors known affect composition and/or diversity. For these reasons, it currently difficult associate determined health status specifically consider

Language: Английский

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Dysbiosis of the gut microbiota in disease

Microbial Ecology in Health and Disease, Journal Year: 2015, Volume and Issue: 26(0)

Published: Feb. 2, 2015

There is growing evidence that dysbiosis of the gut microbiota associated with pathogenesis both intestinal and extra-intestinal disorders.Intestinal disorders include inflammatory bowel disease, irritable syndrome (IBS), coeliac while allergy, asthma, metabolic syndrome, cardiovascular obesity.In many these conditions, mechanisms leading to disease development involves pivotal mutualistic relationship between colonic microbiota, their products, host immune system.The establishment a 'healthy' early in life appears be critical maintaining homeostasis.Whilst we do not yet have clear understanding what constitutes picture emerging from recent studies identifying particular bacterial species healthy microbiota.In particular, residing within mucus layer colon, either through direct contact cells, or indirect communication via metabolites, may influence whether cellular homeostasis maintained are triggered.In addition inflammation, there some perturbations involved colorectal cancer.In this case, most important factor, rather products interaction diet microbiome.High-protein diets thought result production carcinogenic metabolites induction neoplasia epithelium.Ever more sensitive metabolomics methodologies reveal suite small molecules produced microbiome which mimic act as neurosignallers neurotransmitters.Coupled probiotic interventions alter psychological endpoints humans rodent models, data suggest CNS-related co-morbidities frequently GI originate intestine microbial dysbiosis.This review outlines current showing extent contributes disease.Based on date, can assess potential positively modulate composition ameliorate activity intervention.

Language: Английский

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Gut microbiota-derived metabolites as key actors in inflammatory bowel disease

Nature Reviews Gastroenterology & Hepatology, Journal Year: 2020, Volume and Issue: 17(4), P. 223 - 237

Published: Feb. 19, 2020

Language: Английский

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The severity of nonalcoholic fatty liver disease is associated with gut dysbiosis and shift in the metabolic function of the gut microbiota

Hepatology, Journal Year: 2015, Volume and Issue: 63(3), P. 764 - 775

Published: Nov. 24, 2015

Several animal studies have emphasized the role of gut microbiota in nonalcoholic fatty liver disease (NAFLD). However, data about dysbiosis human NAFLD remain scarce literature, especially including whole spectrum lesions. We aimed to evaluate association between and severe lesions, that is, steatohepatitis (NASH) fibrosis, a well-characterized population adult NAFLD. Fifty-seven patients with biopsy-proven were enrolled. Taxonomic composition was determined using 16S ribosomal RNA gene sequencing stool samples. Thirty had F0/F1 fibrosis stage at biopsy (10 NASH), 27 significant F≥2 (25 NASH). Bacteroides abundance significantly increased NASH patients, whereas Prevotella decreased. Ruminococcus higher patients. By multivariate analysis, independently associated fibrosis. Stratification according these two bacteria generated three patient subgroups increasing severity Based on imputed metagenomic profiles, Kyoto Encyclopedia Genes Genomes pathways related mostly carbohydrate, lipid, amino acid metabolism.NAFLD associates shift metabolic function microbiota. identified as Thus, analysis adds information classical predictors suggests novel targets for pre-/probiotics therapies.

Language: Английский

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Prebiotics: Definition, Types, Sources, Mechanisms, and Clinical Applications

Foods, Journal Year: 2019, Volume and Issue: 8(3), P. 92 - 92

Published: March 9, 2019

Prebiotics are a group of nutrients that degraded by gut microbiota. Their relationship with human overall health has been an area increasing interest in recent years. They can feed the intestinal microbiota, and their degradation products short-chain fatty acids released into blood circulation, consequently, affecting not only gastrointestinal tracts but also other distant organs. Fructo-oligosaccharides galacto-oligosaccharides two important groups prebiotics beneficial effects on health. Since low quantities fructo-oligosaccharides naturally exist foods, scientists attempting to produce industrial scale. Considering benefits safety, as well production storage advantages compared probiotics, they seem be fascinating candidates for promoting condition replacement or association probiotics. This review discusses different aspects prebiotics, including crucial role well-being.

Language: Английский

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Emerging pathogenic links between microbiota and the gut–lung axis

Nature Reviews Microbiology, Journal Year: 2016, Volume and Issue: 15(1), P. 55 - 63

Published: Oct. 3, 2016

Language: Английский

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