Inhibitory effects of xanthones on platelet activating factor receptor binding in vitro.
Nine naturally occurring xanthones were investigated for their platelet activating factor (PAF) receptor binding inhibitory effects using rabbit platelets. 2-(3-methylbut-2-enyl)-1,3,5-trihydoxyxanthone, macluraxanthone, 1,3,5-trihydroxy-6,6'-dimethylpyrano(2',3':6,7)-4-(1,1-dimethylprop-2-enyl)xanthone, 6-deoxyjacareubin and 2-(3-methylbut-2-enyl)-1,3,5,6-terahydroxyxanthone showed strong inhibition with IC50 values of 4.8, 11.0, 21.0, 29.0 and 44.0 microM, respectively. The prenyl group at C-2, the dimethylprop-2-enyl group at C-4 and the hydroxyl group at C-5 are all beneficial to the binding of xanthones to the PAF receptor. The results revealed that xanthones can represent a new class of natural PAF receptor antagonists.
Jantan
I
I
Department of Pharmacy, Faculty of Allied Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300, Kuala Lumpur, Malaysia. ibj@medic.ukm.my
Juriyati
J
J
Warif
N A
NA
D000818:Animals; D010980:Platelet Membrane Glycoproteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011485:Protein Binding; D011817:Rabbits; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D014966:Xanthenes / Q000737:chemistry / Q000494:pharmacology*; D044004:Xanthones
D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D014966:Xanthenes; D044004:Xanthones; C039351:platelet activating factor receptor; C009689:xanthone