Fig. 4.
Zn deficiency induces apoptotic cell death in rat cortical neurons. Rat cortical neurons were incubated for 12, 18, or 24 h in control non-chelated medium (C) or chelated media containing 1.5 (1.5 Zn) or 15 μM (15 Zn) Zn. a Cell viability was measured as described in “Materials and methods” section. Results are shown as means ± SEM of four independent experiments. * Significantly different compared to C and 15 μM Zn groups (P < 0.01, one-way ANOVA test). b (Left panel) Caspase-3 activity was measured after 18 h incubation in control non-chelated medium (C) or chelated medium containing 1.5 μM Zn without (1.5 Zn) or with the addition of 0.5 mM α-lipoic acid. (Right panel) Western blot for full-length and cleaved-PARP in total cell extracts isolated from rat cortical neurons incubated for 18 h in the corresponding media. Results are shown as means ± SEM (Fig. 3a, b left panel) or means (Fig. 3b right panel) of two to three independent experiments. * Significantly different compared to C group (P < 0.05, one-way ANOVA test). c Apoptotic cells were also visualized by TUNEL assay and fluorescence microscopy after incubating rat cortical neurons for 24 h in the corresponding media. Fluo fluorescein, PI propidium iodide fluorescence