Yogurt inhibits intestinal barrier dysfunction in Caco-2 cells by increasing tight junctions

Area of Science:

• Gastroenterology
• Cell Biology
• Immunology

Background:

• Chronic inflammation compromises intestinal barrier function, contributing to diseases like obesity.
• Understanding how dietary components modulate gut barrier integrity is crucial for therapeutic interventions.

Purpose of the Study:

• To elucidate the mechanism by which yogurt enhances intestinal barrier function.
• To investigate yogurt's impact on tight junction proteins and cellular permeability in an inflamed intestinal model.

Main Methods:

• Caco-2 cells were utilized as an in vitro model of intestinal permeability.
• Transepithelial electrical resistance (TEER) and paracellular flux assays (FD, LY) measured barrier integrity.
• Immunofluorescence microscopy and quantitative PCR assessed tight junction protein expression and localization.
• Simulated digestion models evaluated yogurt's bioactivity through gastric and intestinal phases.

Main Results:

• Yogurt treatment significantly reduced the inflammatory disruption of Caco-2 cell monolayer integrity (TEER, P < 0.0001).
• Yogurt enhanced the localization and expression of key tight junction proteins, including occludin, ZO-1, and claudin-1.
• The barrier-improving effects of yogurt were partially lost following simulated intestinal digestion.

Conclusions:

• Yogurt ameliorates inflammation-induced intestinal barrier dysfunction in vitro by strengthening tight junctions.
• The bioactivity of yogurt in maintaining gut barrier function is sensitive to digestive processes, particularly in the intestinal phase.