In Vitro Testing of Artificial Sweeteners with Apple and Chokeberry Fruit Juice Extracts for Intestinal Permeability and Glucose Uptake

Higher incidences of sugar-induced obesity and diseases such as diabetes force the development of healthy soft drink alternatives. Fruit juices, rich in beneficial polyphenols and sweeteners instead of sugar, could be a suitable option. The aim of this study was to investigate the influence of the sweeteners saccharin, cyclamate, acesulfame K, aspartame, and sucralose individually and in combination with fruit juice extracts of apple and chokeberry on human intestinal cells. Therefore, a coculture of Caco-2 and HT29-MTX cells was differentiated to form the intestinal epithelium, whereby the mechanistic focus was on intestinal barrier integrity versus glucose transport. In the in vitro system, saccharin alone and in combination with apple extract significantly increased the permeability, while apple polyphenols increased the glucose uptake. This increase was independent of changes in the expression of glucose transports SGLT1, GLUT 1, and GLUT 2. In contrast, aspartame significantly reduced the TEER values, which was prevented by apple polyphenols, but did not affect the permeability or glucose uptake. Thus, sweeteners may influence different mechanisms in the human intestinal cells. In conclusion, polyphenol-rich extracts can reduce or strengthen the effects induced by sweeteners and are, therefore, a promising additive for healthier and sugar-free beverages.