Effects of impressic acid from Acanthopanax koreanum on NF-κB and PPARγ activities.

Impressic acid, 3α,11α-dihydroxylup-20(29)-en-28-oic acid, is a lupane-type triterpenoid isolated from Acanthopanax koreanum, which has been used as a Korean folk medicine for rheumatism, hepatitis, diabetes, and inflammatory disorders. Recently, it was reported that impressic acid has inhibitory effects on the LPS-stimulated pro-inflammatory cytokine production in bone marrow-derived dendritic cells and on the nuclear factor of activated T-cells transcription factor activity. Thus, to investigate whether impressic acid has effects on the inhibition of nuclear factor kappa B (NF-κB) and activation of peroxisome proliferator-activated receptor gamma (PPARγ), luciferase reporter assays were used. The effects on the expression of NF-κB and PPARγ target genes were also examined by reverse transcription-polymerase chain reaction. In this study, impressic acid was found to inhibit tumor necrosis factor (TNF)-α induced NF-κB activity and to up-regulate transcriptional activity of PPARγ.