Neuroprotective Diarylheptanoids from the Leaves and Twigs ofJuglans sinensisagainst Glutamate-Induced Toxicity in HT22 Cells

Abstract

A new diarylheptanoid, juglanin C(1), was isolated from the 80 % methanolic extract of the leaves and twigs of JUGLANS SINENSIS with three known diarylheptanoids, juglanin A(2), juglanin B (3), and (5R)-5-hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1(4-hydroxyphenyl)-3-heptanone (4), using bioactivity-guided fractionation and chromatographic techniques. Among the isolated diarylheptanoids, compounds 1 and 2 significantly showed neuroprotective activities against glutamate-induced toxicity in HT22 cells. These two diarylheptanoids significantly reduced the overproduction of cellular peroxide in glutamate-injured HT22 cells. Moreover, these two diarylheptanoids significantly maintained antioxidative defense systems, including glutathione, glutathione reductase, and glutathione peroxidase, under glutamate-induced oxidative stress in HT22 cells.