Fig. 1.

AMPK activation suppresses neuronal polarization in cultured hippocampal neurons. (A) Time course for AMPK activation (pAMPK) by AICAR (2 mM) in day 1 in vitro (DIV1) hippocampal neurons. (B) Incubation of DIV1 neurons with AICAR and metformin (200 µM) on AMPK activation. (C) Neurons were pretreated with compound C (CC) (20 µM) for 1 hour followed by 30-min incubation with AICAR. (D) Illustration of AICAR treatment paradigm with corresponding polarization stages. (E to G) Effect of AMPK activation by AICAR and metformin on neuronal polarization. (H to J) Measurement of nonaxonal neurite length, axon length, and the total growth. (K and L) Expression of wild-type (WT) or kinase-dead (KD) AMPK on neuronal polarity. Cell numbers of statistical analysis are indicated at the top of bar graphs. *P < 0.05, two-population Student’s t test [(F) and (H) to (J)], or analysis of variance (ANOVA) with Tukey post-test [(G) and (L)]. Scale bar, 20 µm.