Chrysin suppresses lipopolysaccharide-induced cyclooxygenase-2 expression through the inhibition of nuclear factor for IL-6 (NF-IL6) DNA-binding activity

Edited by Frances Shannon

Received 13 September 2004; received in revised form 4 December 2004; accepted 9 December 2004. published online 04 January 2005.

Abstract

Chrysin is a natural, biologically active compound extracted from many plants, honey and propolis. It possesses potent anti-inflammation, anti-cancer and anti-oxidation properties. The mechanism by which chrysin suppresses COX-2 expression remains poorly understood. In the present report, we investigated the effect of chrysin on the expression of COX-2 in lipopolysaccharide (LPS)-activated Raw 264.7 cells. Chrysin significantly suppressed the LPS-induced COX-2 protein and mRNA expression in a dose-dependent manner. The ability of chrysin to suppress the expression of the COX-2 was investigated using luciferase reporters controlled by various cis-elements in COX-2 promoter region. Mutational analysis and electrophoretic mobility shift assay verified that nuclear factor for IL-6 was identified as responsible for the chrysin-mediated COX-2 downregulation. These results will provide new insights into the anti-inflammatory and anti-carcinogenic properties of chrysin.

Keywords: Chrysin, Cyclooxygenase-2, Nuclear factor for IL-6, Macrophage, Lipopolysaccharide

a Department of Immunology, School of Medicine, Keimyung University, 194 DongSan-Dong Jung-Gu, Taegu 700-712, South Korea

b Department of Food Science and Technology, Keimyung University, Taegu, South Korea

c Department of Food Science and Nutrition, Nara Women’s University, Nara, Japan

Corresponding author. Fax: +82 53 250 7074

PII: S0014-5793(04)01604-7

doi:10.1016/j.febslet.2004.12.048

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