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Lanostanes from Phellinus igniarius and their iNOS inhibitory activities
Guei-Jane Wang1, Tung-Hu Tsai, Tun-Tschu Chang
1National Research Institute of Chinese Medicine, Taipei 112, Taiwan.
Planta Medica
|June 27, 2009
Summary
Four new triterpenoids from Phellinus igniarius were identified and tested for their effects on nitric oxide (NO) production. Compound 7 significantly inhibited NO production in activated macrophages, showing potential anti-inflammatory properties.
Area of Science:
- Natural Products Chemistry
- Pharmacology
- Immunology
Background:
- Phellinus igniarius is a fungus known for its medicinal properties.
- Triterpenoids are a class of natural compounds with diverse biological activities.
- Nitric oxide (NO) plays a crucial role in inflammatory processes.
Purpose of the Study:
- To isolate and characterize new triterpenoids from Phellinus igniarius.
- To evaluate the inhibitory effects of isolated compounds on nitric oxide production in macrophages.
Main Methods:
- Isolation of compounds using chromatographic techniques.
- Structure elucidation by spectroscopic analysis (NMR, MS).
- Assessment of nitric oxide production in lipopolysaccharide (LPS)-activated RAW 264.7 cells.
Main Results:
- Four new lanostanol-type triterpenoids (igniarens A-D) and two known triterpenoids were isolated.
- Compounds 1-8 demonstrated varying degrees of inhibition on NO production.
- Compound 7 exhibited significant, dose-dependent inhibition of LPS-induced NO production without cytotoxicity (IC50 = 37.57 ± 1.38 μM).
Conclusions:
- Phellinus igniarius is a source of novel bioactive triterpenoids.
- The isolated triterpenoids, particularly compound 7, possess anti-inflammatory potential by inhibiting NO production.
- Further research is warranted to explore the therapeutic applications of these compounds.
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