The neuroprotective effects of different acetylated neutral oligosaccharides in PC12 cells. (A) PC12 cells were treated with or without different N-acetylated chitosan oligosaccharides N-2~4 at indicated concentrations for 2 h. Then cells were treated with glutamate for another 24 h before performing a resazurin assay. The untreated normal cells (control) were assigned values of 100 and the results presented as mean ± SD (n = 4). Significance: # p < 0.05 vs. normal control group; * p < 0.05 vs. glutamate treated control group. (B) PC12 cells were treated with or without peracetylated chitobiose Q-2, lactose, acetylated lactose, cellobiose, or acetylated cellobiose at indicated concentrations for 2 h. Then cells were treated with glutamate for another 24 h. The untreated normal cells (control) were assigned values of 100 and the results presented as mean ± SD (n = 3). Significance: ## p < 0.01 vs. normal control group; * p < 0.05, ** p < 0.01 vs. glutamate treated control group.