Ethylacetate extract from DraconisResina inhibits LPS-induced inflammatory responses in vascular smooth muscle cells and macrophages via suppression of ROS production

DraconisResina (DR) is a type of dragon’s blood resin obtained from Daemomoropsdraco BL. (Palmae). DR has long been used as a traditional Korean herbal medicine, and is currently used in traditional clinics to treat wounds, tumors, diarrhea, and rheumatism, insect bites and other conditions. In this study, we evaluated fractionated extracts of DR to determine if they inhibited the production of interleukin-1β (IL-1β) and the expression of cyclooxygenase (COX)-2. The results of this analysis revealed that the ethylacetate extract of DraconisResina (DREA) was more potent than that of other extracts. Moreover, DREA inhibited the production of nitric oxide (NO), reactive oxygen species (ROS), prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α), IL-8 and IL-6 in lipopolysaccharide (LPS)-treated human aortic smooth muscle cells (HASMC) and RAW 264.7 macrophages. Furthermore, treatment with an NADPH oxidase assembly inhibitor, AEBSF, efficiently blocked LPS-induced mitogen-activated protein kinases (MAPKs) activation, as did DREA. These findings indicate that DREA inhibits the production of NO, PGE₂, TNF-α, IL-8, and IL-6 by LPS via the inhibition of ROS production, which demonstrates that DREA inhibits LPS-induced inflammatory responses via the suppression of ROS production. Taken together, these results indicate that DREA has the potential for use as an anti-atherosclerosis agent.