Prebiotic mechanisms of resistant starches from dietary beans and pulses on gut microbiome and metabolic health in a humanized murine model of aging

Abstract

Dietary pulses, being a rich source of fiber and proteins, offer an ideal and inexpensive food choice for older adults to promote gut and metabolic health. However, the prebiotic effects of dietary pulses-derived resistant starches (RS), compared to RS from cereals and tubers, remain relatively underexplored, particularly in context to their gut modulatory potential in old age. We herein investigate the prebiotic effects of pulses-derived RS on the gut microbiome and intestinal health in aged (60-week old) mice colonized with human microbiota. C57B6/J mice were fed for 20 weeks with either a western-style high-fat diet (control; CTL) or CTL diet supplemented (5% w/w) with RS from pinto beans (PTB), black-eyed-peas (BEP), lentils (LEN), chickpeas (CKP), or inulin (INU; reference control). We find that the RS supplementation modulates gut microbiome in a sex-dependent manner. For instance, CKP enriched α-diversity only in females, while β-diversity deviated for both sexes. Further, different RS groups exhibited distinct microbiome differences at bacterial phyla and genera levels. Notably, LEN fostered Firmicutes and depleted Proteobacteria abundance, whereas Bacteroidota was promoted by CKP and INU. Genus Dubosiella increased dominantly in males for all groups except PTB, whilst Faecalibaculum decreased in females by CKP and INU groups. Linear discriminant analysis effect size (LEfSe) and correlational analyzes reveal RS-mediated upregulation of key bacterial genera associated with short-chain fatty acids (butyrate) production and suppression of specific pathobionts. Subsequent machine-learning analysis validate decreased abundance of notorious genera, namely, Enterococcus, Odoribacter, Desulfovibrio, Alistipes and Erysipelatoclostridium among RS groups. CKP and LEN groups partly protected males against post-prandial glycemia. Importantly, RS ameliorated high-fat diet-induced gut hyperpermeability and enhanced expression of tight-junction proteins (claudin-1 and claudin-4), which were more pronounced for LEN. In addition, IL10 upregulation was more prominent for LEN, while TNF-α was downregulated by LEN, CKP, and INU. Together, these findings demonstrate that RS supplementation beneficially modulates the gut microbiome with a reduction in gut leakiness and inflammation, indicating their prebiotic potential for functional food and nutritional applications.

Enzymatic Synthesis of α-Glucan Microparticles Using Amylosucrases from Bifidobacterium Species and Its Physicochemical Properties

“…RS is of particular interest due to its health benefits to humans. RS is resistant to human digestive enzymes and is able to reach the colon without being digested early in the gastrointestinal tract, where it is used as an energy source for the gut microbiota . RS fermented by microorganisms in the colon is converted into SCFAs, which play a role in maintaining human health .…”

“…RS is resistant to human digestive enzymes and is able to reach the colon without being digested early in the gastrointestinal tract, where it is used as an energy source for the gut microbiota. 40 RS fermented by microorganisms in the colon is converted into SCFAs, which play a role in maintaining human health. 41 Therefore, the RS contents of the prepared GMPs are important properties for their applications in various fields.…”

Standard rodent diets differentially impact alcohol consumption and preference and gut microbiome diversity

“…Animals fed with TL2019S had lower alcohol preference and consumption and higher abundance of the genus Dubosiella compared to the two other diets. Interestingly, Dubosiella was previously associated with the production of beneficial metabolites, such as short chain fatty-acids (SCFA) (Kadyan et al, 2023). SCFAs such as acetate, butyrate and propionate supplementation is effective in reducing stress-induced gut-brain axis disorders (van de Wouw et al, 2018).…”

A modified Mediterranean-style diet enhances brain function via specific gut-microbiome-brain mechanisms

“…Glucose tolerance test (GTT) and insulin tolerance test (ITT) were completed as described in our previous reports. 95 Tests were conducted subsequent to the collection of the final time-point fecal samples and all behavioral assays. Briefly, for GTT, the mice were fasted for six hours whereafter a glucose solution (2.5 g/kg bodyweight) was orally administered to the mice, and their blood glucose levels were measured at 0 minutes (before the injection), as well as at 15, 30, 60, and 120 minutes after the glucose administration.…”

“…Gut epithelial permeability was measured using the fluorescein isothiocyanate (FITC)-dextran assay as per our previously described method. 95 Tests were conducted subsequent to the collection of the final time-point fecal samples and all behavioral assays. Briefly, the mice were fasted for 4 hours prior to the experiment and were orally administered a solution of fluorescein isothiocyanate (FITC) dextran (4 kDa) at a dose of 60 mg/100 g bodyweight.…”