Xanthones Isolated from the Pericarp of Mangosteen Inhibit Neurotransmitter Receptors Expressed in Xenopus Oocytes.
OBJECTIVE
This study aimed to evaluate inhibitory effects of 7 xanthones and 3 extracts obtained from the pericarp of mangosteen on serotonin (5-HT), N-methyl-D-aspartate (NMDA) and glycine receptors expressed in Xenopus oocytes.


METHODS
Xenopus oocytes were injected with RNA of either 5-HT NMDA or glycine receptor and inhibitory effects of the xanthones and extracts were investigated using the two-electrode voltage clamp technique.


RESULTS
Xanthones from the pericarp of mangosteen affected 5-HT NMDA and glycine receptor functions with different degree of inhibition. Alpha-mangostin, garcinone-D and 9-hydroxycalaba xanthone inhibited 5-H T-induced currents by more than 80%. Gamma-mangostin and garcinone-E did by more than 50%, but not more than 80%. Garcinone-C and garcinone- D inhibited glutamate-induced currents by more than 80%. The alcohol extract did by more than 50%, but not more than 80%. Alpha-mangostin, garcinone-C, garcinone-D, non-tannin extract and the alcohol extract inhibited glycine-induced currents between 50-70%, neither compounds inhibited the currents up to 80%.


CONCLUSIONS
These results suggest that each xanthone derivatives has different selectivity to different types of neurotransmitter receptors.
Pathama
P
Leewanich
Sunit
S
Suksamram
D000818:Animals; D005638:Fruit / Q000737:chemistry; D029762:Garcinia mangostana / Q000737:chemistry*; D018377:Neurotransmitter Agents / Q000037:antagonists & inhibitors*; D009865:Oocytes / Q000187:drug effects; D018009:Receptors, Glycine / Q000037:antagonists & inhibitors; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D011985:Receptors, Serotonin / Q000378:metabolism; D044004:Xanthones / Q000494:pharmacology*; D014981:Xenopus / Q000378:metabolism*
D018377:Neurotransmitter Agents; D018009:Receptors, Glycine; D016194:Receptors, N-Methyl-D-Aspartate; D011985:Receptors, Serotonin; D044004:Xanthones