The sesquiterpene lactone components of Cichorium glandulosum suppress both in vitro and in vivo inflammatory responses by reducing IL-1β levels

This study investigates the anti-inflammatory effects and molecular targets of the chemical components in Cichorium glandulosum. Active compounds were isolated and purified from the ethyl acetate extract of Cichorium glandulosum, and their anti-inflammatory effects were evaluated using both in vitro and in vivo models. The results demonstrated that sesquiterpene lactones in Cichorium glandulosum possess significant anti-inflammatory properties. Molecular docking and biofilm interference analysis revealed that these compounds, particularly compound 4 (Lactucin) and compound 7 (Lactucopicrin), exhibit high affinity for IL-1β, interacting through hydrogen bonds and van der Waals forces, thus inhibiting inflammation. In vitro experiments showed that Lactucin and Lactucopicrin notably reduced the release of NO, IL-6, TNF-α, and IL-1β in LPS-stimulated RAW264.7 cells, highlighting their potent anti-inflammatory activity. Animal studies further confirmed the anti-inflammatory effects of these compounds in an acute inflammation model, with Lactucopicrin demonstrating superior anti-inflammatory efficacy compared to the positive control, indomethacin. Structure-activity relationship studies identified the α-methylene-γ-lactone group in sesquiterpene lactones as the key pharmacophore responsible for their anti-inflammatory activity. In conclusion, sesquiterpene lactones in Cichorium glandulosum inhibit inflammation by targeting IL-1β, demonstrating significant anti-inflammatory potential and providing new theoretical insights into the pharmacological research of active components in Cichorium glandulosum.