BDNF expression in HMC3 cells upon Aβ42 exposure. In (A,B), cells were treated with Aβ42 (0.2 μM) alone or in combination with SIRT1-selective inhibitor EX527 (EX, 5 μM). In (A), Western blot analysis of the intracellular content of BDNF at 6 h in the presence of brefeldin A (5 μg/mL). A representative blot is shown. ELISA determinations of released BDNF are reported at 24 h (B) and 72 h (C). In panel (C), melatonin (MEL, 1 μM) was added to Aβ42, alone or in combination with EX or luzindole (LUZ, 25 μM). Results are the mean ± SEM of 3–5 independent experiments. * p < 0.05 vs. C and ** p < 0.05 vs. Aβ (B) or vs. Aβ+MEL (C) by one-way ANOVA followed by Newman Keuls test for significance.