Effect of Scutellaria baicalensis Extract on the Immune Functions, Microbial Growth and Mutagenicity

Lee, Jeong Ho; Shin, Sook Jeong; Moon, Yong

Abstract

Scute/larisa baica/ensis (SB) has been used as a folk medicine for curing ulcer, inflammation and infection. However, surprisingly little has been done to develop and exploit SB's immunomodulating, anti- inflammatory properties. Moreover, the mechanisms of SB-action on immune function had not been elucidated. The present study was undertaken to investigate the effect of 5B on immune functions, microbial growth and bacterial mutagenicity. Boiling water extract of SB was used in this experiment. The proliferation response to PHA-, Con A- or LPS-stimulation and the production of Con A-induced IL-2 and LPS-induced IL-6 of splenocytes from SB-pretreated mice were significantly higher than those of splenocytes from control mice. Daily single injection of 2 mg/mouse SB for 4 days resulted in enhancement of Arthus reaction and DTH to SRBC. And these enhancements were more prominent when SB was treated prior to SRBC- sensitization. SB did inhibit the growth of microorganisms such as C. albicans, C. neoformans, E. coli S. typhimurium and this inhibiting effect was gradually increased in proportion to the increment of SB. SB also remarkably reduced the mutagenicity of mutagens such as sodium azid and benzo[a]pyrene, but this was not certain, because it showed a killing effect on the cell survival test. When SB treated mice were i.p infected with C. albicans, the number of microorganisms in the peritoneal exudates were significantly reduced. Taken together, these results revealed that SB itself has not only multiple effects on events controlling immune responses but also anti-inflammatory properties, which may provide the rational basis for their therapeutic use as one of the biological response modifiers.