ABSTRACT
Three previously undescribed sesquiterpenes, along with three known ones were isolated from the seeds of Cichorium glandulosum. The structures of them were elucidated by the analysis of spectroscopic data. The isolated compounds were tested for their neuroprotective effects against LPS-induced neuroinflammation in BV-2 cells. Santamarine (5) exhibited inhibitory activity on LPS-induced NO production in BV-2 cells with IC50 of 0.89 ± 0.12 µM. The mechanism of the compound 5 was related to activating the NF-κB, MAPK and cGAS/STING pathways.
ABSTRACT
Eight undescribed guaianolide sesquiterpene lactones cicholosumins A-H and twelve known ones were isolated from the aerial parts of Cichorium glandulosum Boiss et Huet. Their structures were established by 1D and 2D NMR spectroscopic data, electronic circular dichroism, quantum chemical calculations and single crystal X-ray diffraction analysis. Compounds 9α-hydroxy-3-deoxyzaluzanin C, epi-8α-angeloyloxycichoralexin, 8-O-methylsenecioylaustricin and lactucin showed strong anti-neuroinflammation activity with IC50 values of 1.69 ± 0.11, 1.08 ± 0.23, 1.67 ± 0.28 and 1.82 ± 0.27 µM, respectively. The mechanism research indicated that epi-8α-angeloyloxycichoralexin inhibited neuroinflammation through the NF-κB and MAPK pathways.