Ginkgolide B reduces inflammatory protein expression in oxidized low-density lipoprotein-stimulated human vascular endothelial cells.

Ginkgolide B is a herbal constituent extracted from leaves of the ginkgo biloba tree. Previous studies have shown that ginkgolide B is a specific platelet activating factor (PAF) receptor antagonist, and it suppresses PAF-mediated platelet activation via competitive binding. In this study, the effect of ginkgolide B on nicotinamide adenine dinucleotide phosphate oxidase and other inflammatory proteins in ox-LDL (low-density lipoprotein)-stimulated human vascular endothelial cells was investigated. Another PAF receptor antagonist CV3988 was employed to compare with ginkgolide B in this study. Our results show that the enhancement of Nox4 expression and reactive oxygen species generation was attenuated by ginkgolide B in cells treated with ox-LDL but not with CV3988. Increases in monocyte chemoattractant protein-1 and intercellular adhesion molecule 1 expression induced by ox-LDL, however, were inhibited by both ginkgolide B and CV3988. The translocation of NF-kappaB p65 (NF-κB) into the nucleus was inhibited by both ginkgolide B and CV3988. In conclusion, both ginkgolide B and CV3988 can inhibit the expression of inflammatory proteins by blocking NF-κB translocation. It seems that ginkgolide B possesses some pharmacological action on intracellular oxidative stress in association with the downregulation of Nox4 expression.