Host: The Japanese Society of Toxicology
Name : The 51st Annual Meeting of the Japanese Society of Toxicology
Date : July 03, 2024 - July 05, 2024
The small intestine is divided into three segments: duodenum, jejunum, and ileum. Various transporters are expressed for nutrient absorption, and their distribution characterizes the nutrient absorption site. The cholesterol transporter NPC1L1 and bile acid transporter ASBT are therapeutic targets for drug treatment. The small intestine is endowed with biological defenses, including (1) barrier function by mucin layers and tight junctions, (2) active barrier mechanism formed by drug-metabolizing enzymes and transporters, (3) secretion of antibacterial peptides, and (4) immune systems. It also serves as secretory tissue that releases peptide hormones and serotonin to induce biological responses. Villi undergo turnover through a series of processes, including maintenance of undifferentiated cells in the crypts, differentiation into various cells (absorptive epithelial cells, Paneth cells, goblet cells, and enterochromaffin cells), migration to the tip, and detachment from the tip. Perturbation of the small intestine by drugs leads to gastrointestinal toxicity such as diarrhea, nausea, and vomiting. In recent years, various devices have emerged for constructing microenvironments that mimic organ environments, and they have attracted great interest as microphysiological systems (MPS). Expectations are increasing for its use as a model for pharmacokinetic studies and safety evaluation. In this presentation, we also introduce MPS, which is currently under development.
