ginkgolide B

ginkgolide B

Alternative pharmacology
A chemical extracted from the ginkgo tree (Ginkgo biloba), which is a platelet-activating factor (PAF) receptor antagonist that inhibits neutrophil degranulation and superoxide production in vitro, inhibits bronchoconstriction in patients with asthma, is neuroprotective after oral administration and is of potential use in treating circulatory defects in the elderly.
References in periodicals archive ?
Neither GBE (up to 1000 mg/kg) nor ginkgolide B (up to 140 mg/kg), a platelet-activating factor antagonist, influenced blood coagulation parameters.
One of the proposed mechanisms by which GBE could cause bleeding is via the action of ginkgolide B, a constituent of GBE that is reported to be a platelet-activating factor (PAF) antagonist (Smith et al.
Hence, from the available evidence so far, it remains unclear whether GBE and ginkgolide B increase bleeding, and whether GBE enhances the anticoagulant effect of warfarin in vivo.
Ginkgolide B is thought to be neuroprotecrive and antithrombotic; in vitro studies suggest that ginkgo extracts also may influence the release of nitric oxide and may scavenge free radicals (Fitoterapia 1998;69:195-244).
The primary active principles in ginkgo are flavone glycosides and the terpene lactones bilobalide and certain ginkgolides, particularly ginkgolide B.
The 27/7(TM) extract contains 27% flavonoid glycosides and 7% terpene lactones, including substantially more ginkgolide B as contained in other formulations.
The ginkgolides, and particularly ginkgolide B, contribute to ginkgo's effectiveness at inhibiting a potent anti-inflammatory and vasoconstrictor lipid mediator called platelet-activating factor (PAF), which can cause blood platelet aggregation and a diminished flow of blood.
The biological activity of methanolic the extracts of leaves, roots, leaf-derived callus, root-derived callus, ginkolide A, ginkgolide B, bilobalide and a commercial Ginkgo product (Tanakan[R]) was assessed.
Louis, USA: ginkgolide A, 90% purity, ginkgolide B, 90% purity; bilobalide, 95% purity.
Under the chosen experimental conditions, PAF-mediated aggregation of human platelets was half-maximally inhibited by ginkgolide B, A, C and J at concentrations of 2.
The sequence of anti-PAF potency in both species was identical with ginkgolide B exerting by far the most powerful antagonistic effect (Figs.