Fig. 8

ER stress response to N-GQDs was caused by RyR channel mediated calcium imhomeostasis in BV2 cells. a Representative fluorescent images of ER calcium level in BV2 cells showed green using meg-Fluo4 dye with HBSS containing EDTA without calcium and magnesium. The ER showed red using ER-Tracker Red, and the nucleus showed blue using DAPI, Scale bar: 20 µm; b, c the protein expressions of GRP78, CHOP and ATF4 in BV2 cells using western blotting analysis. BV2 cells were pre-treated with dantrolene and BAPTA-AM for 2 h and then exposed to 100 µg/mL N-GQDs for 24 h (n = 3). Data are showed as mean ± SD of three independent experiments. The one-way ANOVA followed by the Dunnett’s t test were used to determine statistical significance (*P < 0.05, **P < 0.01, ***P < 0.001 vs. the control or 100 µg/mL N-GQDs)