S. barbata의 열수 추출물 (Sb-HWE)은 대표적인 염증과정인 LPS에 의해 활성화된 대식세포로 부터의 NO생성, LPS 매개에 의한 세포사멸작용, 및 FITC-dextran의 대식세포내 탐식작용을 매우 효과적으로 억제하였다. 그러나 본 추출물은 SNP로 유도된 라디칼 소거능은 매우 미약한 것으로 나타났다. NF-kB-매개에 의한 루시퍼라제 활성, 및 NF-kB 활성 관련 신호전달 단백질 (Akt 및 IkBα)에 대한 저해작용은 관찰되지 않은 것으로 보아 이들 추출물의 대식세포 면역반응 조절 기전은 기존의 알려진 방법과는 다른 기전에 의해 진행되는 것으로 판단된다.
Scutellaria barbata was examined to evaluate its modulatory effects on the functional activation of macrophages under lipopolysaccharide (LPS) treatment. To do this, hot water extract (Sb-HWE) was prepared from Scutellaria barbata and several inflammatory parameters such as nitric oxide (NO) production, phagocytosis, reactive oxygen species (ROS) determination and intracellular signaling pathway were selected to be tested. Sb-HWE strongly blocked NO production in LPS-activated RAW264.7 cells in a dose-dependent manner. However, it did not suppress inducible NO synthase (iNOS). In agreement, Sb-HWE did not diminish inflammatory signaling composed of NF-kB and its upstream activation signaling enzymes such as Akt and IkBα. Sb-HWE protected RAW264.7 cells from LPS-induced cytotoxicity up to 80% at 400 μg/ml. Furthermore, this extract blocked phagocytic uptake of FITC-dextran, while sodium nitroprusside (SNP)-induced ROS generation in RAW264.7 cells was not decreased. Therefore, our data suggest that Sb-HWE may have differential immunoregulatory function depending on macrophage-mediated immune responses.