Neuroprotective effects of constituents of Eragrostis ferruginea against Aβ-induced toxicity in PC12 cells

A new flavonoid, 7-demethylageconyflavone A (1), and five known compounds, tricin (2), ageconyflavone A (3), corylin (4), nectandrin B (5), and 4-ketopinoresinol (6) were isolated from the aerial parts of Eragrostis ferruginea. Their structures were determined using spectroscopic techniques, including 1D- and 2D-NMR. All compounds were tested for the neuroprotective effects against amyloid beta peptide (Aβ) using PC12 cells, a major cause of the pathology of Alzheimer's disease. Tricin (2) was found to have a neuroprotective effect with an ED₅₀ value of 20.3 μM against Aβ-induced toxicity in PC12 cells. Ageconyflavone A (3), nectandrin B (5) and 4-ketopinoresinol (6) demonstrated moderate neuroprotective effects with ED₅₀ values of 58.7, 44.1, and 54.8 μM, respectively.