Abstract
Isoegomaketone (IK) is a known component of Perilla frutescens that reportedly exhibits anti‑inflammatory, anti‑cancer and anti‑allergic properties. A novel compound known as 9‑HIK has been isolated from the extract of a radiation mutant P. frutescens var. crispa using supercritical carbon dioxide. In the present study, 9‑HIK induced heme oxygenase‑1 (HO‑1) mRNA expression in RAW264.7 cells, with maximal levels observed 4 h after 9‑HIK treatment. In addition, 9‑HIK inhibited the mRNA and protein expression of pro‑inflammatory mediators, such as IL‑6 and interferon‑β, as well as the production of nitric oxide (NO) in lipopolysaccharide‑stimulated RAW264.7 cells. Furthermore, N‑acetyl‑L‑cysteine, a reactive oxygen species scavenger, inhibited NO production and HO‑1 mRNA expression levels through the nuclear factor erythroid 2‑related factor 2 pathway. Overall, 9‑HIK displayed anti‑inflammatory properties in LPS‑induced RAW264.7 cells via direct suppression of inflammatory mediators and HO‑1 induction.