Inhibition of AMPK in SCD1-deficient INS-1E cells increases DNMT1 protein levels and prevents gDNA hypomethylation under conditions of SCD1 deficiency. (A,B) DNMT1 levels in INS-1E cells that were co-treated with the SCD1 inhibitor A939572 (SCD1i) (A), siSCD1 (B), palmitic acid (16:0), and 10 µM compound c to block AMPK. The levels of AMPK phosphorylation at Thr172 (pAMPK Thr172) and SIRT1 and DNMT1 protein content were measured by Western blot. (C,D) Effect of AMPK inhibition by compound c on gDNA methylation levels in INS-1E cells with the inhibition of SCD1 activity (C) and SCD1 gene silencing (siSCD1) (D). * p < 0.05, vs. Vehicle/siCtrl; ^ p < 0.05, vs. 16:0/16:0+siCtrl, & p < 0.05, && p < 0.005, vs. siSCD1/SCD1i; # p < 0.05, ## p < 0.005, vs. SCD1i/siSCD1+16:0. The data are expressed as the mean ± SD of three independent experiments. AMPK: adenosine monophosphate-activated protein kinase; SIRT1: NAD-dependent deacetylase sirtuin-1.