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Small bowel resection induces long-term changes in the enteric microbiota of mice.

ABSTRACT: The enteric microbiome is known to play a major role in healthy gut homeostasis and several disease states. It may also contribute to both the intestinal recovery and complications that occur in patients with short bowel syndrome. The extent and nature of alterations to the gut microbiota following intestinal resection, however, are not well studied in a controlled setting. The purpose of this investigation is to characterize the effects of massive small bowel resection on the murine enteric microflora.Wild-type C57BL6 mice, following a week of acclamation to a liquid rodent diet, underwent either 50% proximal small bowel resection (SBR) or a sham operation. Mice were sacrificed, and enteric contents from the small bowel, cecum, and stool were harvested at 7 and 90 days post-operatively. DNA was isolated, and the V3-V5 regions of the 16s rRNA gene amplified and pyrosequenced on a Roche 454 platform. Sequences were clustered into operation taxonomic units and classified. Communities were then analyzed for diversity and phylogenic composition.In the long-term group, the microbes inhabiting the ileum of mice undergoing SBR and sham operation differed significantly at the genus level (p?

SUBMITTER: Sommovilla J

PROVIDER: S-EPMC4576885 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Small bowel resection induces long-term changes in the enteric microbiota of mice.

Sommovilla J J Zhou Y Y Sun R C RC Choi P M PM Diaz-Miron J J Shaikh N N Sodergren E E Warner B B BB Weinstock G M GM Tarr P I PI Warner B W BW

Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract 20140903 1

<h4>Purpose</h4>The enteric microbiome is known to play a major role in healthy gut homeostasis and several disease states. It may also contribute to both the intestinal recovery and complications that occur in patients with short bowel syndrome. The extent and nature of alterations to the gut microbiota following intestinal resection, however, are not well studied in a controlled setting. The purpose of this investigation is to characterize the effects of massive small bowel resection on the mu ...[more]

PMID: 25183407

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Project description:Background & aimsThe small intestine (SI) displays regionality in nutrient and immunological function. Following SI tissue loss (as occurs in short gut syndrome, or SGS), remaining SI must compensate, or "adapt"; the capacity of SI epithelium to reprogram its regional identity has not been described. Here, we apply single-cell resolution analyses to characterize molecular changes underpinning adaptation to SGS.MethodsSingle-cell RNA sequencing was performed on epithelial cells isolated from distal SI of mice following 50% proximal small bowel resection (SBR) vs sham surgery. Single-cell profiles were clustered based on transcriptional similarity, reconstructing differentiation events from intestinal stem cells (ISCs) through to mature enterocytes. An unsupervised computational approach to score cell identity was used to quantify changes in regional (proximal vs distal) SI identity, validated using immunofluorescence, immunohistochemistry, qPCR, western blotting, and RNA-FISH.ResultsUniform Manifold Approximation and Projection-based clustering and visualization revealed differentiation trajectories from ISCs to mature enterocytes in sham and SBR. Cell identity scoring demonstrated segregation of enterocytes by regional SI identity: SBR enterocytes assumed more mature proximal identities. This was associated with significant upregulation of lipid metabolism and oxidative stress gene expression, which was validated via orthogonal analyses. Observed upstream transcriptional changes suggest retinoid metabolism and proximal transcription factor Creb3l3 drive proximalization of cell identity in response to SBR.ConclusionsAdaptation to proximal SBR involves regional reprogramming of ileal enterocytes toward a proximal identity. Interventions bolstering the endogenous reprogramming capacity of SI enterocytes-conceivably by engaging the retinoid metabolism pathway-merit further investigation, as they may increase enteral feeding tolerance, and obviate intestinal failure, in SGS.

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Small bowel resection induces long-term changes in the enteric microbiota of mice.

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Small bowel resection induces long-term changes in the enteric microbiota of mice.

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