Abstract
Grape pomace (GP) is a winemaking by-product rich in polyphenols and fibre. Supplementation with GP extracts has shown potential benefits against oxidative stress- and inflammation-related pathologies. As a new nutritional target, this paper explores the impact of the ingestion of a grape pomace extract on intestinal barrier functionality. A GP extract was sequentially subjected to gastrointestinal and colonic digestion using the dynamic gastrointestinal simulator (simgi®). This generated two simulated fluids: intestinal-digested extract (IDE) and colonic-digested extract (CDE). The effects of these two fluids on paracellular permeability and the expression of tight junction (TJ) proteins (i.e., zonula occludens-1 (ZO-1) and occludin) were assessed in Caco-2-cell monolayers grown in Transwell® inserts. The IDE fluid significantly (p < 0.001) reduced the paracellular transport of FITC-dextran with respect to the control, whereas no significant differences (p > 0.05) were found for CDE, which could be due, at least partially, to the pro-leaky effect of the colonic digestion medium. Accordant slight increases in the mRNA levels of both ZO-1 and occludin were observed for IDE, but without statistical significance. Additionally, the colonic fermentation of the GP extract promoted the production of short-chain fatty acids (SCFA) and phenolic metabolites and led to changes in the relative abundance of some bacteria that might affect paracellular permeability. Overall, this paper reports first trends about the effects of grape pomace extracts on intestinal permeability that would require further confirmation in future experiments.
Highlights
Grapes are the fourth-most commonly harvested fruit in the world [1], with 57% of all harvests (44.37 million tons) acquisitioned for winemaking
The colonic fermentation of the Grape pomace (GP) extract promoted the production of short-chain fatty acids (SCFA) and phenolic metabolites and led to changes in the relative abundance of some bacteria that might affect paracellular permeability
At the level of the small intestine, the extract seemed to reduce paracellular permeability compared to the sample containing only the intestinal-digestion medium (IDM) and slightly increased mRNA levels of both ZO-1 and occludin
Summary
Grapes are the fourth-most commonly harvested fruit in the world [1], with 57% of all harvests (44.37 million tons) acquisitioned for winemaking. In this process, by-products represent around 20–30% of the total amount of processed grapes [2]. Grape pomace (GP), the solid residue left after must extraction (white grape varieties) or wine fermentation (red grape varieties), is especially rich in polyphenols and dietary fibre, which has made it a promising bioactive ingredient for food products, cosmetics, and more [3]. Several investigations have been successfully executed to evaluate GP’s properties as a modulator of blood pressure, fasting, plasma glucose, serum lipids, and obesity, among others [7,8,9]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
