Insulin withdrawal activated GSK-3β. (A) Insulin withdrawal activated GSK-3β, as shown by the decrease in the inhibitory phosphorylation level of serine 9 and the reduction in the β-catenin level. Accompanied by inactivation of AKT, autophagy induction was manifested by an increase in the LC3-II level. Representative results from at least three independent experiments are shown. (B) Quantitative analyses of the LC3-II and β-catenin levels after normalization to β-actin, and phos-GSK-3β level after normalization to total-GSK-3β. Quantitative data are presented as the mean ± SD (n = 3). *p < 0.05, **p < 0.01. Statistical significance was determined with unpaired Student’s t- test.