Anti-inflammatory Effects of Different Fractions Isolated from Modified Boyanghwano-tang Extract in LPS-stimulated Microglial Cells

ABSTRACT Objectives : In this study, the effects of different fractions isolated from modified Boyanghwano- tang(mBHT) extract on LPS-induced inflammation in BV2 microglial cells were investigated.Methods : mBHT was extracted with water, and then fractionated with n-hexane, methylene chloride, ethylacetate and n-butanol. BV2 cells, a mouse microglia line were incubated with different concentrations of each fraction of mBHT for 30 min, a nd then stimulated with LPS for 24 h. Cell toxicity was determined by MTT assay. The concentration of nitric oxide (NO) was measured in culture medium by Griess reagent assay. The express ion of inducible nitric oxide synthease (iNOS) protein was determined by Western blot. Results : Four fractions of mBHT were significantly inhibited LPS-induce d NO productions in BV2 cells in a dose-dependent manner. The methylene chloride fracti on of mBHT was most strongly inhibited the NO production compared with those of the others. The methylene chloride fraction of mBHT was also suppressed LPS-induced iNOS expression comparison of other fractions at same concentration (50 ㎍/㎖) in BV2 cells. Conclusions : The results showed that the methylene chloride fraction of mBH T may have an strong anti-inflammatory property through the inhibition of NO production and iNOS expression in activated microglia, and could a therapeutic potential for the treatment of various brain inflammatory diseases. Key words : Boyanghwano-tang, inflammation, microglia, nitric oxide