등골나물 추출물의 항염증 효과

Abstract

Eupatorium japonicum belongs to a family of Asteraceae plants and flowers of E. japonicum have been consumed as a tea. In this study, we investigated whether E. japonicum extract inhibits lipopolysaccharide (LPS)-induced inflammatory responses in Raw264.7 macrophages. The cells were treated with various concentrations (0, 1, 2.5, 5, or 10 ㎎/l) of 70% ethanol extract from E. japonicum flowers (EJE) in Raw264.7 cells. LPS-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production were inhibited by EJE up to 67% and 49% of these productions, respectively without any reduction of viable cell numbers. EJE reduced LPS-induced expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 proteins and their corresponding mRNA levels. Additionally, EJE decreased the levels of interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α mRNA. EJE was further fractionated with water, butanol, ethylacetate (EA), hexane, or methylene chloride (MC). Among the resulting five fractions, EA and MC, respectively from EJE significantly inhibited LPS-induced NO production (each inhibition rate was 85.3% of 10 ㎎/l EA fraction and 97.2% of 10 ㎎/l MC fraction) without significant cytotoxicity in Raw264.7 cells. These results indicate that EJE exhibits powerful effects of anti-inflammation and can be developed as a potential anti-inflammatory agent.