10439-20-0Relevant academic research and scientific papers
The flavone hispidulin, a benzodiazepine receptor ligand with positive allosteric properties, traverses the blood-brain barrier and exhibits anticonvulsive effects
Kavvadias, Dominique,Sand, Philipp,Youdim, Kuresh A.,Qaiser, M. Zeeshan,Rice-Evans, Catherine,Baur, Roland,Sigel, Erwin,Rausch, Wolf-Dieter,Riederer, Peter,Schreier, Peter
, p. 811 - 820 (2004)
1 The functional characterization of hispidulin (4′,5,7-trihydroxy-6- methoxyflavone), a potent benzodiazepine (BZD) receptor ligand, was initiated to determine its potential as a modulator of central nervous system activity. 2 After chemical synthesis, hispidulin was investigated at recombinant GABA A/BZD receptors expressed by Xenopus laevis oocytes. Concentrations of 50 nM and higher stimulated the GABA-induced chloride currents at tested receptor subtypes (α 1-3,5,6β2γ2S) indicating positive allosteric properties. Maximal stimulation at α1β 2γ2S was observed with 10 μM hispidulin. In contrast to diazepam, hispidulin modulated the α6β 2γ2S-GABAA receptor subtype. 3 When fed to seizure-prone Mongolian gerbils (Meriones unguiculatus) in a model of epilepsy, hispidulin (10 mg kg-1 body weight (BW) per day) and diazepam (2 mg kg-1 BW per day) markedly reduced the number of animals suffering from seizures after 7 days of treatment (30 and 25% of animals in the respective treatment groups, vs 80% in the vehicle group). 4 Permeability across the blood-brain barrier for the chemically synthesized, 14C-labelled hispidulin was confirmed by a rat in situ perfusion model. With an uptake rate (Kin) of 1.14 ml min-1 g -1, measurements approached the values obtained with highly penetrating compounds such as diazepam. 5 Experiments with Caco-2 cells predict that orally administered hispidulin enters circulation in its intact form. At a concentration of 30 μM, the flavone crossed the monolayer without degradation as verified by the absence of glucuronidated metabolites.
