In a pharmacokinetic study, rats were orally dosed with 50 mg/kg bw of extract from Rhizoma Belamcandae; which corresponds to 27.0 mg/kg of irigenin. A maximum plasma concentration (405.08 ng/mL) of Irigenin was achieved within half an hour, suggesting rapid absorption through the stomach.

RAW 264.7 cells were transfected wit hpNF-kB-SEAP-NPT plasmid to introduce the SEAP reporter gene for NF-kB activity. Irigenin was isolated from extracts of the rhizomes of B. chinensis. Cells were stimulated with 100 ng/mL of lipopolysaccharide (LPS) for 18 hours to induce iNOS. Irigenin was then added to cell cultures in doses of 3, 10, or 30 microM. After 18 hours of Irigenine treatment, cultures were assayed (using the Griess Method) for effects on Nitrous Oxide production, PGE2 production, and iNOS enzyme activity. Irigenin significantly reduced NO production and PGE2 production. Furthermore, Irigenin inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COS-2) and mRNAs without appreciable cytotoxic effects. Irigenin also appears to have lowered the NF-kB activity in the cells, as measured by electrophoretic mobility shift assay. These results suggest that Irrigenin may be interesting as an anti-inflammatory molecule.