Abstract
- Background
Dietary prebiotics pectin and resistant starch type-4 promote satiety and alter gut microbiota; however, the underlying neurohormonal mechanisms of satiety remain poorly understood. This study determined the effects of pectin, resistant starch type-4, and their combination on energy balance and gut microbiota composition, and assessed whether the gut hormones peptide YY and cholecystokinin play a role in fiber-induced satiety.
- Methods
High-fat diet-induced obese male rats were fed either a control, pectin, resistant starch type-4, or a combination of pectin and resistant starch type-4 diet. Food intake, substrate utilization, body weight gains, and adiposity were monitored. Plasma concentrations and expression of peptide YY and cholecystokinin were assessed, alongside systemic receptor blockades. Additionally, fecal microbiota composition and metabolite concentrations were analyzed.
- Results
Pectin, resistant starch type-4, and their combination decreased food intake. Pectin alone or combined with the starch shifted substrate utilization toward fat and reduced weight and adiposity gains while enhancing expression and plasma concentrations of peptide YY and cholecystokinin. Systemic blockade of peptide YY-Y2 and cholecystokinin-1 receptors attenuated the hypophagic effects of pectin, and cholecystokinin-1 receptor blockade partly attenuated the hypophagia from resistant starch type-4. Furthermore, prebiotics significantly altered fecal beta-diversity metrics, increased the relative abundance of Bacteroidota, decreased Firmicutes, and elevated amino acid and biogenic amine concentrations.
- Conclusions
Dietary pectin and resistant starch type-4 improve energy balance and gut microbiota composition, and the satiety effects of these diets are mediated, in part, via enhanced endogenous peptide YY and cholecystokinin signaling.
https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fj.202403239R