Effect of the extracts from Glycyrrhiza uralensis Fisch on the growth characteristics of human cell lines:: Anti-tumor and immune activation activities

Immune modulating activity of ethanol extracts from Glycyrrhiza uralensis Fisch was investigated by conserving growth characteristics of several human cell lines. All of the samples did not show severe cytotoxicity on normal human liver cell line, WRL-68, showing less than 25% inhibition of cell growth. The crude extract and its fractionized samples (F1 and F3) inhibited the growth of human hepatoma, Hep3B, down to ca. 70% of normal cell growth in adding 1.0 g l(-1) of fraction F3. The result of anticancer experiments was well matched to the results of antimutagenicity using Chinese Hamster Lung cell lines (CHL V79). In adding 1.0 g l(-1) of fraction F1, the growth of human B cell was enhanced, up to 60% of control growth. The secretion of two kinds of cytokines, Interleukin-6 and Tumor Necrosis Factor-alpha from human B cells was also enhanced in adding the crude extract, but not the standards such as Glycyrrhizin (GL) or 18,beta-glycyrrhetinic acid (GM). It was found that both of the apoptosis and differentiation were more accelerated in supplementing the crude extract and fraction F1 than in adding the standards. A spot was found only in the crude extract and fractions, not standards by Thin Layer Chromatography (TLC) analysis. It tells that there must be another unknown component in crude and/or fraction F1 as a possible candidate of immune modulators. This component seems to be a derivative of a monomer, GM since its R-f was close to the monomer. It was also interesting that glycyrrhizin, a major component in G. uralensis Fisch was biologically activated by first being hydrolyzed by an enzyme.