To explore whether palmitic acid (PA) can induce ferroptosis in pancreatic beta-cell line MIN6 cells.

Pancreatic beta-cell line MIN6 cells were divided into normal group, PA group (1.0 mmol/L), PA+apoptosis inhibitor (Z-VAD-FMK) group (5 μmol/L), PA+ ferrostain-1(Fer-1) group (5 μmol/L), PA+ necrostatin-1(Nec-1) group (5 μmol/L). Each group was set three parallels. Cell viability was detected by CCK8 method. Cellular ultrastructure was assessed with electron microscopy. FerroOrange was used to detect intracellular Fe²⁺. The lipid peroxidation assay kit was used to detect the concentration of malondialdehyde (MDA). Flow cytometry was used to detect intracellular reactive oxygen species (ROS) levels. Real-time quantitative polymerase chain reaction was used to detect the mRNA levels of caspase3, receptor-interacting protein kinase 3 (RIPK3), acyl-CoA synthetase long-chain family member 4 (ACSL4), prostaglandin endoperoxidase synthase 2 (Ptgs2), arachidonate lipoxygenase 15 (ALOX15), ferritin heavy chain (FTH), ferritin light chain (FTL), and glutathione peroxidase 4 (GPX4). Western blotting was used to detect the proteins levels of cleaved caspase3, RIPK3, ACSL4, ALOX15 and Ptgs2. The t-test was used to compare two groups.

Compared with the PA group, cell viability of MIN6 was higher in PA+Z-VAD-FMK group, PA+Fer-1 group or PA+Nec-1 group (P<0.01). MIN6 cells, which were treated with PA to exhibit the characteristic morphologic features, were associated with apoptosis, necrosis and ferroptosis under electron microscope. Compared with the control group, in PA group, the levels of the cellular intracellular Fe²⁺, MDA and total lipid ROS were increased. The mRNA relative expression levels of caspase3, RIPK3, ACSL4, Ptgs2 and ALOX15 were increased. The mRNA relative expression levels of FTH and GPX4 were decreased. The protein relative expression levels of cleaved caspase3, RIPK3, ACSL4, ALOX15 and Ptgs2 were increased (all P<0.01). Compared with the PA group, in PA+Fer-1 group, the levels of cellular intracellular Fe²⁺, MDA and total lipid ROS were decreased. The mRNA relative expression levels of ACSL4, Ptgs2 and ALOX15 were decreased. The mRNA relative expression levels of FTH and GPX4 were increased. The protein relative expression levels of ACSL4, ALOX15 and Ptgs2 were decreased (all P<0.01).

PA could induce ferroptosis in pancreatic beta-cell line MIN6 cells.

Palmitic acid; Ferroptosis; MIN6 cells