FIGURE 4.

The neuroprotective effects of fluoxetine against Aβ_1-42-induced toxicity are mediated by TGF-β1. Mixed cortical cultures were challenged with Aβ_1-42 oligomers (1 μM) for 48 h in the absence or presence of fluoxetine (1 μM) applied alone or combined with the selective inhibitor of Smad-dependent TGF-β1 signaling, SB431542 (SB; 10 μM) or with a neutralizing antibody specific for TGF-β1 (anti-TGF-β1) applied at a concentration of 2 μg/ml. Aβ toxicity in mixed neuronal cultures was assessed by cell counting after trypan blue staining. Cell counts was performed in three random microscopic fields/well. Values are expressed as percentage of Aβ_1-42 toxicity and are means ± SEM of nine determinations ^∗p < 0.05 vs. Aβ alone (Aβ_1-42, vhl) and #Aβ + fluoxetine (Aβ_1-42, Flx, vhl) (One-way ANOVA + Bonferroni’s test).