The effect of baicalin on inducible nitric oxide synthase and cyclooxygenase-2 expression in lipopolysaccharide-treated macrophage RAW264.7

Autor: Weng-Jean Yu, 余宛真
Rok vydání: 2001
Druh dokumentu: 學位論文 ; thesis
Popis: 89
It has been demonstrated that baicalin extracted from the root of Huangquin, a Chinese herb medicine has potential antioxidant and anti-inflammatory effect. Many studies have indicated that overproduction of nitric oxide (NO), from inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2) from cyclooxygenase-2 (COX-2), free radical, and tumor necrosis factor-a (TNF-a) is involved in the pathogenesis of septic shock. In this study, we evaluated the effect of baicalin on these mediators and iNOS as well as COX-2 expression in lipopolysaccharide (LPS)-treated RAW264.7 macrophage. Our results demonstrated that baicalin ( 10~50 mM ) concentration-dependently inhibited LPS-induced NO、TNF-a and PGE2 production in LPS-treated RAW264.7 macrophage without an appreciable cytotoxic effect. Furthermore, baicalin inhibited the expression of LPS-induced iNOS and COX-2 proteins and mRNAs. These results indicated that the inhibition of TNF-a production by baicalin maybe contribute to the suppression of iNOS and COX-2 expressions. Thus, baicalin may be beneficial for treatment of endotoxaemia. Besides, treatment of the RAW264.7 macrophage with 50 mM baicalin decreased the S phase and G2/M phase ratio about 15% in the cell cycle. Thus, baicalin may be also a potential therapeutic drug for tumor therapy.
Databáze: Networked Digital Library of Theses & Dissertations