posted on 2021-05-27, 06:43authored byHung-Tse Huang, Chia-Ching Liaw, Chun-Tang Chiou, Yao-Haur Kuo, Kung-Ta Lee
Five new triterpene acids, mesonaic
acids A–C (1–3), 2α,3α,19α-trihydroxy-24-nor-4(23),12-oleanadien-28-oic
acid (4), and 3α,19α,22α-trihydroxy-2-oxo-12-ursen-28-oic
acid (5), and 10 known triterpene acid compounds (6–15) were isolated from a methanolic
extract of Mesona procumbens. Triterpenes 1–3 possess unusual hexacyclic skeletons with
a 13α,27-cyclopropane ring. Regarding their anti-inflammatory
activity, compounds 1–3, 6, and 7 inhibited NO production with EC50 values lower than 15 μM, which were better than that of the
positive control quercetin. Compounds 1–3, 6, and 7 markedly decreased levels
of the inducible iNOS and COX-2 proteins in macrophages by inhibiting
the activation of NF-κB through interference with the MAPK signaling
pathway. Based on these data, compounds 1–3, 6, and 7 have great potential
as NO inhibitors.