Fig. 1

VCP is highly expressed in HCN cells and degraded through autophagy following insulin withdrawal. a VCP was abundantly expressed in HCN cells compared with hippocampal tissue prepared from 8-week-old rat and embryonic primary hippocampal neurons (9 days in vitro). b VCP was particularly localized in hippocampal neural stem cells in vivo, as indicated by arrowheads. GFAP and MAP2 were used as NSC and neuronal markers, respectively. Scale bar, 20 μm. c VCP protein level was significantly decreased at 48 h following insulin withdrawal. Quantitative analysis of VCP levels was normalized to β-actin. Quantitative data are represented at the mean ± SD (n = 3). Statistical significance was determined with an One-way ANOVA test by Tukey’s multiple comparison test. *p < 0.05. d VCP expression levels were decreased in ex vivo organotypic hippocampal slice culture following insulin withdrawal for 24 h. Arrow indicates the VCP-expressing HCN cells in I(+) condition, while arrowheads show the loss of VCP expression in I(-) condition. Scale bar, 20 μm. e Expression levels of VCP mRNA were not changed by insulin withdrawal. Quantitative data are represented at the mean ± SD (n = 3). n.s. not significant. f Degradation of VCP was prevented by Bafilomycin A1 treatment (BafA1, 30 nM for 3 h before harvest) following 48 h insulin withdrawal