Fig. 2: PXDN silence reduces cell death by promoting autophagy.

A H9C2 cells were treated with 50 μM si-negative control (NC) or si-PXDN in serum-free medium for 24 h, and treated with 400 μM palmitate acid (PA) or bovine serum albumin (BSA) for another 24 h. Cell survival was evaluated using fluorescence staining with calcein acetoxymethyl ester (Calcein-AM) for live cells in green and ethidium homodimer-1 (EthD-1) for dead cells in red. The percentage of cell death was shown in the right side (scale bar = 50 μM, n = 4). B AC16 cells were treated with si-NC or si-PXDN in serum-free medium for 24 h, and treated with PA or BSA for another 24 h. Cell survival was evaluated using fluorescence staining. The percentage of cell death was shown in the right side (scale bar = 50 μM, n = 4). C Autophagosomes and autolysosomes in H9C2 with si-NC or si-PXDN in the absence or presence of PA were detected by transmission electron microscopy. Black Arrow referred to autophagosomes and white arrow referred to autolysosomes. The number of autophagosomes and autolysosomes per cell was shown in the right side (scale bar = 20 μm in top and 6 μm in bottom, respectively. n = 3). D H9C2 cells were treated with 50 μM si-NC or si-PXDN in serum-free medium for 24 h, and treated with 400 μM PA or BSA with or without 1 μM DC661 for another 24 h. PXDN, LC3II, and p62 levels were detected by Western blot and quantitative analyses were shown below (n = 4–8). Data were presented as mean ± SEM. One-way ANOVA test was used. *P < 0.05, **P < 0.01, ***P < 0.001.