Ginkgo biloba extract inhibits oxygen species production generated by phorbol myristate acetate stimulated human leukocytes |
| |
| Authors: | J Pincemail A Thirion M Dupuis P Braquet K Drieu C Deby |
| |
| Institution: | (1) Laboratoire de Biochimie et de Radiobiologie, Institut de Chimie, B6, Université de Liège, Sart-Tilman, B-4000 Liège 1, Belgique;(2) Centre de Transfusion Sanguine de Liège, rue Dos Fanchon, B-4000 Liège, Belgique;(3) IHB, IPSEN Institute for Therapeutic Research, F-92350 Le Plessis-Robinson, France |
| |
| Abstract: | Summary A Ginkgo biloba extract (Gbe) containing flavonoids, among other compounds, was tested for the release of activated oxygen species (
, H2O2, OH.) during the stimulation of human neutrophils (PMNs) by a soluble agonist. The extract slows down O2-consumption (respiratory burst) of stimulated cells by its inhibitory action on NADPH-oxidase, the enzyme responsible for the reduction of O2 to
. Consequently, superoxide anion (
) and hydrogen peroxide (H2O2) production is significantly decreased when the PMNs stimulation is done in the presence of the extract at concentrations of 500, 250 and 125  g/ml. Moreover, the hydroxyl radical generation (OH.) is very much decreased at concentrations as low as 15.6 g Gbe/ml, which indicates that the extract also has free radical scavenging activity. Gbe is able at least to reduce very severel the activity of myeloperoxidase contained in neutrophils. This enzyme, secreted into the intra and extracellular medium, catalyzes the oxidation of chloride (Cl–) by H2O2 to yield strong oxidants (HOCl, chloramines) which are implicated in inflammatory processes |
| |
| Keywords: | Ginkgo activated leukocytes oxygen radical scavenger |
| 本文献已被 SpringerLink 等数据库收录！ |
|
