Modeling and Characterization of Intestinal Senescence Using Human Organoids: Insights Into the Epithelial to Mesenchymal Transition.

Intestinal senescence is an important factor in systemic aging and age-related diseases; however, detailed studies have been limited due to the lack of robust experimental models. In this study, we established cellular senescence models of human small intestinal organoids using two senescence-inducing agents: butyrate (an endogenous microbial metabolite) and cisplatin (an exogenous chemotherapeutic agent). Both molecules induced senescence-associated features, including increased p16INK4a, CDKN1A, IL8, and TNF expression, as well as SA-β-Gal activity. RNA-sequencing revealed that cisplatin, but not butyrate, activated the p53 signaling pathway, whereas both downregulated various nutrient absorption and metabolism-related pathways. These models exhibited reduced nutrient transporter expression, diminished glucose uptake, and decreased vitamin D responsiveness, thus recapitulating the features of aged or damaged intestinal tissue. In cisplatin-treated organoids, epithelial to mesenchymal transition (EMT)-related gene ontologies were enriched based on RNA-sequencing. The induction of EMT through cisplatin-induced senescence was further confirmed by EMT marker gene expression, which decreased following the inhibition of TGF-β signaling, a canonical EMT-inducing pathway. Notably, TGF-β signaling inhibition attenuated senescence-induced inflammation and nutrient dysfunction, which suggests the importance of EMT as a target for preventing intestinal senescence. Our models provide a novel platform for examining the intestine-specific molecular mechanisms of senescence associated with distinct senescence-inducing mechanisms and for developing strategies to prevent age-related intestinal dysfunction.