Figure 4

Valproate pretreatment protects β - cells from palmitate-induced apoptosis via GSK-3β inhibition. (A) With presence or absence of 1 mM VPA pretreatment, INS-1 cells were exposed to 0.25 mM PA for 48 h. The expressions of phospho-GSK-3β and cleaved caspase-3 were detected by Western blot. GAPDH protein served as loading control. The intensity of protein bands was quantified by densitometry and expressed as fold change compared with control. Data are mean ± SD of three independent experiments. **P < 0.01; ^§P < 0.001. (B) INS-1 cells were pretreated with VPA, LiCl or TDZD-8 before challenged with 0.25 mM PA for the times indicated on the X-axis. After the treatments, cell viability was measured by CCK-8 assay. The figure shows representative results of three independent experiments. The given values are mean ± SD of at least five duplicate wells. ^§P < 0.001 vs. 0.25 mM PA; &P < 0.001 vs. 0.25 mM PA + 1 mM VPA.