INHIBITION OF PHOSPHOLIPASE-C ACTIVITY BY AURICULATIN AND 8-PRENYLLUTEONE ISOLATED FROM ERYTHRINA-SENEGALENSIS

Auriculatin and 8-prenylluteone were isolated from Erythrina senegalen sis (Leguminosae) as inhibitors of phospholipase C (PLC) and phosphoin ositides (PI)-turnover in PLC-gamma 1 overexpressing NIH3T3 fibroblast s (NIH3T3 gamma 1). Auriculatin (1) and 8-prenylluteone (2) showed inh ibitory activity with an IC50 value of 20 mu M on PLC in vitro as well as the formation of inositol phosphates in platelet-derived growth fa ctor (PDGF)-stimulated NIH3T3 gamma 1 cells. They also showed a modera te cytotoxicity against several human tumour cell lines with an IC50 o f 9.0-20 mu M, i.e. PC-3 (prostate), NCI-H226 (lung), CRL1579 (melanom a) in vitro. (C) 1998 John Wiley & Sons, Ltd.