Inhibitory effects of phenolic compounds from needles of Pinus densiflora on nitric oxide and PGE2 production.

The needles of Pinus densiflora Siebold et Zuccarini, a representative Pinus species that grows in Korea, have been used in oriental traditional medicine as remedies for rheumatitis, hemorrhage, cancer, etc. Phytochemical examination of the needles of Pinus densiflora Siebold et Zuccarini led to the isolation of four lignans, one flavan-3-ol, two flavonols and one organic acid. They were identified as icariside E(4) (1), cupressoside A (2), schizandriside (3), (+)-isolariciresinol (4), (+)-catechin (5), quercetin 3-O-β-D-glucopyranoside (6), 5,7,8,4'-tetrahydroxy-3-methoxy-6-methylflavone 8-O-β-D-glucopyranoside (7) and (-)-shikimic acid (8). In order to evaluate the anti-inflammatory effects of these compounds, their inhibitory activities against nitric oxide and prostaglandin E(2) production in IFN-γ- and lipopolysaccharide-stimulated RAW 264.7 cells were examined.