Anti-inflammatory effects of glycyrol isolated from Glycyrrhiza uralensis in LPS-stimulated RAW264.7 macrophages

• DOI: 10.1016/j.intimp.2008.06.008
• Publication Date: 2008-07-14T22:15:44Z
• Authors: Eun Myoung Shin; Hong Yu Zhou; Lian Yu Guo; Jeong Ah Kim; Seung Ho Lee; Irmgard Merfort; Sam Sik Kang; Hak Sung Kim; Sanghee Kim; Yeong Shik Kim
• Keywords: Flavonoids; Inflammation; Lipopolysaccharides; Male; 0301 basic medicine; Cell Survival; Interleukin-6; Macrophages; Anti-Inflammatory Agents, Non-Steroidal; Interleukin-1beta; Anti-Inflammatory Agents; Nitric Oxide Synthase Type II; Carrageenan; Nitric Oxide; Cell Line; I-kappa B Kinase; 3. Good health; Mice; 03 medical and health sciences; Cyclooxygenase 2; Animals; Edema; Glycyrrhiza uralensis

The anti-inflammatory effects of glycyrol, a benzofuran coumarin isolated from Glycyrrhizae Radix, were studied. Glycyrol of 5, 25 and 50 microM dose-dependently inhibited nitric oxide (NO) production by down-regulating inducible nitric oxide synthase (iNOS), and alleviated cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW264.7 macrophages, in both the mRNA and the protein. Furthermore, glycyrol dose-dependently decreased the mRNA of the pro-inflammatory cytokines IL-1beta and IL-6. LPS-induced NF-kappaB activation was prevented in RAW264.7 macrophages by inhibition of I-kappaBalpha phosphorylation. In addition, administration of glycyrol (30 and 100 mg/kg, i.p) reduced the thickness of carrageenan-induced mouse-paw edema swelling. Taken together, our results indicate that glycyrol is an important anti-inflammatory constituent of Glycyrrhizae Radix, and that its anti-inflammatory effect is attributed to the inhibition I-kappaBalpha phosphorylation.