Figure 2. AICAR-mediated AMPK activation induces tau phosphorylation in primary neurons.

Primary neurons at 15 DIV were treated for the indicated times with the AMPK activator AICAR (1 mM). AMPK and ACC expression and activation were monitored by Western-blot (WB) using antibodies against AMPK, p-Thr¹⁷²AMPK (pAMPK), ACC, p-Ser⁷⁹ACC (pACC) and actin (a). Quantifications of the ratios AMPK/actin (b) pAMPK/AMPK (c) and pACC/ACC (d). WB analysis (e) and quantification of total tau (f) and phosphorylated tau at epitopes Ser^262/356 (g), Thr²³¹ (h), Ser^396/404 (i) and Ser²⁰² (j) expressed in ratios. Cytotoxicity assay following 6 h and 24 h AICAR treatments in primary neurons at 15 DIV determined using the lactate dehydrogenase (LDH) test (k). Treatment with 0.9% Triton X-100 was used as a positive control. Results represent mean ± SD, n = 4–6. a.u., arbitrary units. *p < 0.05, **p < 0.01, ***p < 0.001 compared to Ctrl, One way ANOVA with Bonferroni’s post hoc test.