Naringin Protects against Tau Hyperphosphorylation in Aβ_25–35-Injured PC12 Cells through Modulation of ER, PI3K/AKT, and GSK-3β Signaling Pathways

Figure 4

Effect of naringin on the viability of PC12 cells injured by Aβ_25–35. Cell viability was measured by MTT assays after exposure to the following treatments. (a) PC12 cells were incubated with different concentrations of naringin (100 pM, 1 nM, 10 nM, 100 nM, 1 μM, 10 μM, 100 μM, and 1 mM) or E₂ (1 nM) for 24 hours. (b) PC12 cells were incubated with naringin (100 pM, 1 nM, 10 nM, 100 nM, 1 μM, 10 μM, and 100 μM) or E₂ (1 nM) for 2 hours, then treated with Aβ_25–35 (20 μM) for another 24 hours. (c) PC12 cells were precultured with ICI182780 (1 μM) or LY294002 (50 μM) for 1 hour, then treated with naringin (1 μM) or E₂ (1 nM) for 2 hours, and then treated with Aβ_25–35 (20 μM) for another 24 hours; or precultured with LiCl (10 mM) for 2 hours, then treated with Aβ_25–35 (20 μM) for another 24 hours. Data are expressed as the mean ± SD (). Compared with the untreated cells, *, **; compared with Aβ_2s5–35-treated cells, ^##; compared with the treatment group, ^▲▲.

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