Peracetylated chitosan oligosaccharides protect PC12 cells against glutamate-induced Cyto C release from mitochondria. (A) After being pretreated with 200 μg/mL of different PACO monomers Q-2, Q-3 and Q-4 for 2 h and 4 mM of glutamate for another 24 h, the protein levels of Cyto C were evaluated by western blot. Blots were also probed for β-actin as loading controls. The result shown is a representative of three separate experiments with similar results; (B) Quantification of immunoblot for the ratio of Cyto C to β-actin. The ratio for non-treated control cells was assigned values of 1.0 and the data 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. (C–H) After being pretreated with 200 μg/mL of PACO monomers Q-2, Q-3 and Q-4 for 2 h, PC12 cells were exposed to 4 mM glutamate for 24 h. Then the levels of Cyto C in the cytoplasm were detected by immunofluorescence assay using anti-Cyto C antibody. C: Normal control, D: Glu, E: Glu + HupA, F: Glu + Q2, G: Glu + Q3, H: Glu + Q4. Scale bar represents 20 μm.