Comparative Study of the Methanol and Water Extracts of Dangguisoo-san in Suppressing Inflammatory Reaction

Dangguisoo-san (DGSS), a traditional Korean herbal formula, has been prescribed to patients who suffer from various symptoms related with blood stagnation. Since inflammation can cause blood stagnation, we hypothesized that DGSS suppresses inflammation, relieving the symptoms associated with blood stagnation. In this study, given that DGSS is prepared in a mix of alcohol and water, we prepared the methanol (mDGSS) and water extract (wDGSS) of DGSS and compared their activities in suppressing inflammatory reaction. Western blot analyses show that mDGSS was more effective than wDGSS in activating Nrf2, a key factor that suppresses inflammation. Semi-quantitative RT-PCR shows that mDGSS activating Nrf2 resulted in the induction of Nrf2-dependent genes expression. However, mDGSS was not effective in suppressing the nuclear translocation of $NF-{\kappa}B$, a key factor that promotes inflammation, and the expression of $NF-{\kappa}B$-dependent genes such as TNF-a and IL-1b. When comparing with wDGSS, mDGSS was less effective in suppressing luciferase activity driven by $NF-{\kappa}B$. Therefore, our results show that mDGSS has the anti-inflammatory function by mainly activating Nrf2, while wDGSS does by both activating Nrf2 and suppressing $NF-{\kappa}B$. Our results suggest that preparing DGSS in a mix of water and methanol is a better way to achieve a strong anti-inflammatory efficacy of DGSS.