Anti-inflammatory and Antiosteoporosis Flavonoids from the Rhizomes of Helminthostachys zeylanica
- J Nat Prod. 2017 Feb 24;80(2):246-253. doi: 10.1021/acs.jnatprod.5b01164.
- 1. National Research Institute of Chinese Medicine, Ministry of Health and Welfare , No. 155-1, Sec. 2, Li-Nung Street, Peitou, Taipei 11221, Taiwan.
- 2. Department of Cosmetic Science, Chang Gung University of Science and Technology , Taoyuan 33302, Taiwan.
- 3. Institute of Biomedical Sciences, National Chung-Hsing University , Taichung 40227, Taiwan.
- 4. National Taipei University of Nursing and Health Science , Taipei, Taiwan.
- 5. Department of Biotechnology, Hungkuang University , Taichung 433, Taiwan.
Chemical investigation of the rhizomes of Helminthostachys zeylanica led to the isolation of eight new Flavonoids including six cyclized geranylflavonoids, ugonins V-X (1-3), (10R,11S)-ugonin N (4), (10R,11S)-ugonin S (5), and ugonin Y (6), as well as two quercetin glucosides, quercetin-4'-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (7) and quercetin-3-O-β-d-glucopyranosyl-4'-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (8). The structures of these compounds were established by spectroscopic analyses and acid hydrolysis of the sugar moiety. Among the isolated compounds, 1, 2, 5, 6, ugonins J-S (9-13), ugonstilbene A (14), and ugonin L (23) were evaluated for their anti-inflammatory activity on lipopolysaccharide-induced nitric oxide (NO) production in microglial cells. Except for 1, 5, and 13, all Other compounds inhibited NO production with IC50 values of 6.2-10.1 μM and were more potent than the positive control, pyrrolidine dithiocarbamate. Compounds 1, 2, 5, 6, and 10-13 were tested for antiosteoporotic activities, and ugonin K (10) exhibited the highest inhibitory activity against RANKL-induced osteoclast differentiation in RAW264.7 cells with an IC50 value of 1.8 ± 0.2 μM.