Diterpenoids from the soft coral Sinularia maxima and their inhibitory effects on lipopolysaccharide-stimulated production of pro-inflammatory cytokines in bone marrow-derived dendritic cells

Abstract

Nine new diterpenoids, termed sinumaximols A-I (1-3, 5-9, 12), together with three known compounds (4, 10, 11), were isolated from the methanol extract of the soft coral Sinularia maxima . Their structures were elucidated on the basis of extensive spectroscopic methods, including one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The isolated compounds were evaluated for their inhibitory effects on the lipopolysaccharide (LPS)-stimulated production of pro-inflammatory cytokines in bone marrow-derived dendritic cells (BMDCs). Among them, compounds 2, 3, and 11 were potent inhibitors of LPS-stimulated interleukin-12 (IL-12) p40 with half-maximal inhibitory concentration ( IC50) values ranging from 4.35±0.12 to 18.04±0.21 μM. Compounds 2, 3, and 11 showed moderate inhibitory activity on IL-6 production with IC50values ranging from 17.72±0.31 to 59.77±2.34 μM. © 2012 The Pharmaceutical Society of Japan.