Anti-inflammatory Ingenane Diterpenoids from the Roots of Euphorbia kansui

Abstract

Bioassay-guided fractionation of the ethanolic extract of the roots of Euphorbia kansui led to the isolation of two new ingenane diterpenoids, euphorkans A (1) and B (2), together with 16 known analogues (3 – 18). Their structures were determined by combined spectral and chemical methods. All the isolates were evaluated for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophage cells. Compounds 1 – 6 and 10 – 13 exhibited pronounced inhibitory activity with IC₅₀ values in the range of 2.78 – 10.6 µM, and were more potent than the positive control, quercetin (IC₅₀ = 15.8 µM). Compounds 1 and 5 were selected for further assays toward the key inflammation mediators TNF-α and IL-6, and showed a significant inhibition in a dose-dependent manner. The preliminary mechanistic study revealed that 1 and 5 inhibited NF-κB activity, which may exert a role in their anti-inflammatory activity.

Key words

Euphorbia kansui - Euphorbiaceae - ingenane diterpenoids - NO production - anti-inflammatory - NF-κB

• References

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