Fig. 3.

Neuroprotection by Chi-DSNPs on H₂O₂ Challenged BV-2 Cells. a BV-2 cells were incubated with 0.1 mg/ml Chi-DSNPs of different sizes immediately or 15 min after challenging with 5500 μM H₂O₂. The data in H₂O₂ treated groups was normalized and compared with medium–medium treated group (***P < 0.001). The administration of 5 μm filtered group Chi-DSNPs, both at 0 min and post 15 min, enhanced cell viability significantly compared with H₂O₂-medium treated group (^{^^}P < 0.01). Trypan blue was used to detect dead cells. All data was represented mean ± SD. b BV-2 cells were pre-incubated with 0.2 mg/ml Chi-DSNPs (pre-filtered with 1.2 or 5 μm syringe filter) for 4 h and then challenged with 50 μM H₂O₂ for 20 h. Cell proliferation was detected by WST assay. Data represented as mean ± SD. Cell proliferation was inhibited significantly by long-exposure of H₂O₂. An increasing of cell proliferation was observed in H₂O₂ challenged cells treated with 1.2 μm filtered Chi-DSNPs group (1.2 μm-NPs), and no difference was detected between injured control and Chi-DSNPs treatment (*P < 0.05, **P < 0.01, ***P < 0.001)