Dual independent mechanisms underlying gut epithelial remodeling upon sugar substitute consumption

Intestinal epithelial cells (IECs) are dynamically regulated by luminal contents, including dietary ingredients, food additives, and microbiota-derived metabolites. Although sugar substitutes are commonly used as food additives for their sweet taste and lower calorie content, there is limited experimental evidence regarding their potential to drive gut remodeling. In this study, we designed experimental models for short-term consumption of erythritol, a natural sugar alcohol widely used as a sugar substitute, and investigated its effects on gut remodeling and the underlying mechanisms. Our findings indicate that erythritol consumption induces hyperplasia in tuft cells (TCs) and goblet cells (GCs), as well as enhances the activity of intestinal stem cells-increases in expression levels of leucine-rich repeat containing G protein-coupled receptor 5 (Lgr5), the key intestinal stem cell marker, in the number of proliferating stem cells, and facilitation of their differentiation into villi cells-while maintaining the number of Lgr5⁺ intestinal stem cells. Notably, the enhanced stem cell activity was observed even in Trpm5 knockout mice, suggesting that it is mechanistically independent of TC hyperplasia. Instead, we demonstrated the functional involvement of the gut microbiota, as antibiotic treatment abolished this effect, and fecal material transfer from erythritol-consumed mice replicated the enhancement of stem cell activity in recipient mice. Furthermore, we identified acetate as the metabolite responsible for enhancing stem cell activity. These findings suggest the functional decoupling of TC hyperplasia and the enhancement of stem cell activity, providing a potential therapeutic avenue for gut epithelial diseases.