Abstract
The bioassay-guided fractionation of a MeOH extract of the heartwood of Caesalpinia sappan L. provided two neuroprotective compounds, sappanchalcone (2) and 4-O-methylepisappanol (3), together with a methoxychalcone, isoliquiritigenin 2′-methyl ether (1), and three aromatic compounds, 4-O-methylsappanol (4), caesalpine J (5), pluchoic acid (6). At concentrations of 20—40 μm, compound 2 showed significant cytoprotective effects against glutamate-induced oxidative stress through the induction of heme oxygenase (HO)-1 in HT22-immortalized hippocampal cells. Compound 3 also showed moderate neuroprotective effect at 40 μm, but compounds 1, 4—6 did not show any protective effects against glutamate-induced cytotoxicity in HT22 cells.
