Exosome-like nanovesicles from Peucedanum Japonicum directly regulate inflammatory cytokines via small RNAs.

Inflammation plays a key role in the pathogenesis of various diseases, including inflammatory bowel diseases such as ulcerative colitis and Crohn's disease. Similar to animals, plant cells produce exosome-like nanovesicles (ELNs) that play a role in transmitting biological signals from specific types of cells or tissues to other cells or tissues. Here we show that ELNs derived from Peucedanum japonicum (PjELNs) exhibit potent anti-inflammatory effects on macrophages and are effective in a mouse colitis model induced by dextran sodium sulfate (DSS). RNA sequence analysis reveals that PjELNs suppress multiple inflammatory cytokine-mediated signaling pathways in LPS-stimulated macrophage cell lines. We further show that PjENLs promote the differentiation of goblet cells, thereby enhancing mucin production and providing a protective effect on mucosal damage in a DSS-induced murine model of colitis. We also demonstrate that PjELNs inhibit the DSS-induced reduction in the number of transit amplifying cells. PjELNs exhibit anti-inflammatory properties, partly due to the presence of miRNA-like small RNAs that directly regulate the expression of the inflammatory cytokine IL6. Importantly, these small RNAs exhibit cross-species effects in both humans and mice. These findings reveal the mechanism by which plant-derived ELNs modulate inflammatory responses, suggesting their potential as a preventive and therapeutic strategy for inflammatory diseases of the colon.