Phospholipase Cγ1 Inhibitory Activities of Prenylated Flavonoids Isolated from Erythrina senegalensis

Abstract

Prenylated flavonoids isolated from Erythrina senegalensis were evaluated for their ability to inhibit PLCγ1 activity in vitro and the formation of inositol phosphates (IPt) in PLCγ1-overexpressing NIH3T3 fibroblast cells (NIH3T3γ1 cells). These flavonoids inhibited PLCγ1 activity in a dose-dependent manner (IC₅₀ values ranged from 1.0 μg/mL to 35.0 μg/mL) with the exception of alpinumisoflavone (5). Also erysenegalensein D (2) and erysenegalensein N (3) showed inhibition of inositol phosphate formation in NIH3T3γ1 cells with IC₅₀ values of 13.0 μg/mL and 10 μg/mL, respectively. Analyzing the relation of structure to activity, the number of prenyl groups and the hydroxylation of the prenyl groups were important factors for the inhibition of PLCγ1 activity and of inositol phosphate formation.

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