Gut bacteria selectively promoted by dietary fibers alleviate type 2 diabetes

Abstract

The gut microbiota benefits humans via short-chain fatty acid (SCFA) production from carbohydrate fermentation, and deficiency in SCFA production is associated with type 2 diabetes mellitus (T2DM). We conducted a randomized clinical study of specifically designed isoenergetic diets, together with fecal shotgun metagenomics, to show that a select group of SCFA-producing strains was promoted by dietary fibers and that most other potential producers were either diminished or unchanged in patients with T2DM. When the fiber-promoted SCFA producers were present in greater diversity and abundance, participants had better improvement in hemoglobin A1c levels, partly via increased glucagon-like peptide-1 production. Promotion of these positive responders diminished producers of metabolically detrimental compounds such as indole and hydrogen sulfide. Targeted restoration of these SCFA producers may present a novel ecological approach for managing T2DM.

Phellinus linteus polysaccharide extract improves insulin resistance by regulating gut microbiota composition

“…38,39 Analysis of fecal samples of type 2 diabetes patients revealed reductions of gut microbiota diversity and abundance of butyrate-producing bacteria (eg, Roseburia, Faecalibacterium prausnitzii), and increased levels of certain conditionally pathogenic bacteria such as Escherichia coli. 9,18 Dietary polysaccharides are important energy sources for microbiota in cecum and colon. 9,18 Dietary polysaccharides are important energy sources for microbiota in cecum and colon.…”

“…In the present study, the PLPE group showed reduced levels of LPS-producing Escherichia-Shigella, 11 necrotic enteritis-related Clostridium_sensu_stricto_1, 47 conditionally pathogenic Bacteroidales_S24-7_group, 43 and intestinal mucin-degraded Akkermansia. 18 The improvement in intestinal barrier may be mediated by high levels of SCFA observed following PLPE administration. However, when dietary fiber polysaccharides are lacking, this species may damage the mucus layer that functions as a primary barrier against invading pathogens.…”

“…11,15 Addition of Agaricus bisporus powder to the diet of mice increased abundance of succinate-producing Prevotella bacteria and SCFA content in the intestinal tract, thereby improving glucose tolerance. 18 SCFAs are the major energy source for enterocytes, and promote intestinal epithelial growth by enhancing barrier function. 18 SCFAs are the major energy source for enterocytes, and promote intestinal epithelial growth by enhancing barrier function.…”

Faecalibacterium prausnitzii‐derived microbial anti‐inflammatory molecule regulates intestinal integrity in diabetes mellitus mice via modulating tight junction protein expression

“…Recent findings suggest that moderate gut dysbiosis exists in DM patients and animal models . Although the characteristics of the DM gut microbiome are still mired in controversy, gut microbiome studies have hinted at the biological functions or pathogenic roles of gut microbiota in DM progression . The differential richness of specific bacteria is potentially correlated with DM development .…”

Gut microbiome interventions in human health and diseases

“…Above, we established that an HFD is an inducer of various diseases in which intestinal microbiota plays a mediating role, and one question that arises is what type of diet can help establish a good intestinal microbiota. Dietary fiber intake is associated with reduced risks and improvement of a range of diseases from inflammation and infection to metabolic disorders as well as increased abundance of SCFA‐producing bacteria, such as Prevotella . The mechanism appears to involve the beneficial effects of SCFAs on metabolism, inflammation suppression, and antibody response promotion, as discussed above.…”