The epithelial gut barrier and gut microbiota significantly contribute to human health by controlling molecule absorption, a regulated transport that dictates bioavailability. Effective public health strategies, like dietary reference values, require a complete understanding of nutrient absorption. However, the lack of internationally harmonized nutritional recommendations indicates that gut barrier mechanisms are not fully unraveled. The conventional in vitro model Caco-2/HT29-MTX cultured on cell culture inserts, established for drug development, is limited in representing complex human gut physiology. The new bioelectronic e-transmembrane platform leverages technological and biological advances to generate more meaningful in vitro predictions. The soft electroactive Poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) scaffold enables direct cell-electrode coupling for more sensitive barrier impedance measurements, especially required for testing commonly low physiological nutrient concentrations. Promoted epithelial-fibroblast interactions result in modulated protein signal transduction and expression of genes regulating gut barrier integrity. Overall, the e-transmembrane gut barrier more closely mimicked physiological effects for humans as demonstrated using the dietary compound butyrate.
Keywords: absorption; advanced in vitro models; bioelectronics; butyrate; gut; impedance; nutrition.
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