Delving the depths of 'terra incognita' in the human intestine - the small intestinal microbiota.

Journal

Nature reviews. Gastroenterology & hepatology

ISSN: 1759-5053

Titre abrégé: Nat Rev Gastroenterol Hepatol

Pays: England

ID NLM: 101500079

Informations de publication

Date de publication:
23 Oct 2024

Historique:

accepted: 25 09 2024

medline: 24 10 2024

pubmed: 24 10 2024

entrez: 24 10 2024

Statut: aheadofprint

Résumé

The small intestinal microbiota has a crucial role in gastrointestinal health, affecting digestion, immune function, bile acid homeostasis and nutrient metabolism. The challenges of accessibility at this site mean that our knowledge of the small intestinal microbiota is less developed than of the colonic or faecal microbiota. Here, we summarize the features and fluctuations of the microbiota along the small intestinal tract, focusing on humans, and discuss physicochemical factors and assessment methods, including the technical challenges of investigating the low microbial biomass of the proximal small bowel. We highlight the essential protective mechanisms of the small intestine, including motility, the paracellular barrier and mucus, and secretory immunity, to show their roles in limiting excessive exposure of host tissues to microbial metabolites. We address current knowledge gaps, particularly the variability among individuals, the effects of dysbiosis of the small intestinal microbiota on health and how different taxa in small intestinal microbiota could compensate for each other functionally.

Identifiants

DOI: 10.1038/s41575-024-01000-4 PMID: 39443711

pubmed: 39443711

doi: 10.1038/s41575-024-01000-4

pii: 10.1038/s41575-024-01000-4

doi:

Types de publication

Journal Article Review

Langues

eng

Sous-ensembles de citation

Informations de copyright

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