AGS-IV protects against glutamate-induced neurotoxicity in PC12 cells.

(A) Dose-dependent cell death was observed after the cells were treated with different concentrations glutamate for 24 h. (B) Effects of 50 μM AGS-IV, 6-O-β-D-glu CAG, 3-O-β-D-xyl CAG, and CAG on glutamate-induced PC12 cell neurotoxicity. (C) Survival of PC12 cells after exposure to 0.1% DMSO or various concentrations of AGS-IV for 30 h. (D, E) Effects of AGS-IV on glutamate-induced PC12 cell injury. PC12 cells were treated with 10, 25, 50 and 100 μM AGS-IV and then co-incubated with or without 5 mM glutamate for 24 h, and cell cytotoxicity was determined by MTT assay and LDH activity. (F) Apoptosis assay of PC12 cells exposed to glutamate and/or AGS-IV were examined by flow cytometry. PC12 cells were gated for an annexin V+ (x-axis) versus PI+ (y-axis) contour plot. The numbers on dot plots represent the percentages of annexin V+/PI+ cells and annexin V+/PI- cells. (G) The percentage of living cells was tested by trypan blue exclusion for PC12 cells exposed to glutamate and/or AGS-IV. All the data are presented as mean ± SEM of three independent experiments. ## < 0.01 versus vehicle and **P < 0.01 versus glutamate by one-way ANOVA analysis of variance with Tukey’s HSD post hoc test.