[Effects of glycyrrhizin acid and licorice flavonoids on LPS-induced cytokines expression in macrophage].

Glycyrrhizin acid and licorice flavonoids are the component of Glycyrrhiza uralensis Fisch root that has been used for various medicinal purposes in traditional oriental medicine for thousands of years. Macrophages as a principal component of immune system play an important role in the initiation, modulation and final activation of immune response against pathogens. In the present study, glycyrrhizin acid and licorice flavonoids was investigated the anti-inflammatory effect on lipopolysaccharide (LPS)-induced macrophage cell line of RAW264.7. Well-grown RAW264.7 cells were collected and randomly divided into the blank control group, the LPS(1 mg x L(-1)) group, the dexamethasone (5 mg x L(-1)) with LPS group, the glycyrrhizin acid (400, 80, 16 mg x L(-1)) with LPS group and the licorice flavonoids (200, 40, 8 mg x L(-1)) with LPS group. RAW264.7 cells were cultured in 24-well plates, pre-incubated for 4 h with different concentrations of dexamethasone, glycyrrhizin acid, or licorice flavonoids. Then cells were stimulated for 20 h with LPS. The supernatant of culture medium was collected from each well and determinated the concentrations of cytokines by means of BioPlex mouse cytokines assay. Compared with the control group, the LPS group could significantly induced relatively high levels of granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor( GM-CSF), macrophage inflammatory protein-1 alpha (MIP-1α), macrophage inflammatory protein-1 beta (MIP-1β), regulated upon activation normal T cell expressed and secreted factor (RANTES), tumor necrosis factor alpha ( TNF-α), monocyte chemotactic protein 1 (MCP-1), chemokine (C-X-C motif) ligand 1 (KC), eotaxin, interleukin(IL)-1α, IL-1β, IL-3, IL-4, IL-5, IL-6, IL-10, IL-12 (p40), IL-12 (p70), IL-13, and IL-17 secretion (P < 0.05). The glycyrrhizin acid significantly inhibited IL-1β, IL-3, IL-5, IL-6, IL-10, IL-12 (p40), IL-12 (p70), IL-13, Eotaxin and TNF-α secreted by LPS-stimulated RAW264.7 cells (P < 0.05). The expression levels of IL-6 and Eotaxin were observably decreased in the licorice flavonoids with LPS group (P < 0.05). The data presented here suggested that the glycyrrhizin acid and licorice flavonoids modulate various cytokines secreted by macrophages and were important anti-inflammatory constituent of Licorice.