Diterpenoids with anti-inflammatory activities from Isodon rubescens

Area of Science:

• Natural Products Chemistry
• Pharmacology

Background:

• Isodon rubescens is a plant source of bioactive compounds.
• Diterpenoids are a class of natural products with diverse biological activities.

Purpose of the Study:

• To isolate and characterize new diterpenoids from Isodon rubescens.
• To evaluate the anti-inflammatory potential of isolated compounds.

Main Methods:

• Isolation of compounds using chromatographic techniques.
• Structure elucidation via mass spectrometry and X-ray crystallography.
• In vitro anti-inflammatory assay using lipopolysaccharide-stimulated RAW264.7 cells.

Main Results:

• Nine new diterpenoids (Henanabinins A-I) and 14 known analogues were isolated.
• Structures of new compounds were determined, with compound 1's absolute configuration confirmed by X-ray diffraction.
• Compound 10 (rubescensin B) showed potent inhibition of NF-κB nuclear translocation (IC50 = 3.073 μM) and no cytotoxicity at 12.5 μM.

Conclusions:

• Isodon rubescens is a rich source of structurally diverse diterpenoids.
• Rubescensin B exhibits promising anti-inflammatory properties via NF-κB inhibition.
• Further investigation into rubescensin B as a potential anti-inflammatory agent is warranted.