Asiaticasics A-O, structurally intriguing coumarins from Toddalia asiatica with potential inflammatory inhibitory activity.

Ethyl acetate fraction of Toddalia asiatica was fractionated to yield fifteen previously undescribed prenylated coumarins, asiaticasics A-O (1 – 15) along with nine (16 – 24) known derivatives. The structures of these undescribed coumarins were established by spectroscopic analysis and reference data. Biological activity evaluation showed that compound 3 with the IC 50 value of 2.830 μM and compound 12 with the IC 50 value of 0.682 μM owned anti-inflammatory activity by detecting the rate of lactate dehydrogenase release in pyroptosis J774A.1 cells. The results showed that the expression of Caspase-1 and IL-1 β was decreased in a dose-dependent manner in the compound 12 treatment group, suggesting that compound 12 may reduce pyroptosis by inhibiting NLRP3 inflammasome. To further determine that compound 12 treatment can inhibit macrophage pyroptosis, morphological observation was performed and the results were consistent with the bioactivity evaluation. [Display omitted] • Twenty-four coumarins were isolated from the ethyl acetate fraction of Toddalia asiatica. • Fifteen coumarins that have not been described before. • Two undescribed compounds showed low IC 50 values and could exert effective anti-inflammatory effects. • Compound 12 inhibited pyroptosis in a dose-dependent manner. [ABSTRACT FROM AUTHOR]