Fig. 4

HMGB2 mediates LPS-induced autophagy of alveolar epithelial cells by stimulating ROS to produce oxidative stress and activating JNK signalling. A and B The expressions of miR-223 and HMGB2 in A549 cells transfected with sh-HMGB2 or sh-NC plus LPS were assessed by RT-qPCR. C Representative western blot results of HMGB2, JNK, p-JNK and β-actin expressions in A549 cells transfected with sh-HMGB2 or sh-NC plus LPS. D The effect of HMGB2 knockdown plus LPS treatment or LPS treatment on A549 cell apoptosis was assessed by flow cytometry. E The Fluorescent probe was used to detect the ROS level in A549 cells transfected with sh-HMGB2 or sh-NC plus LPS treatment. F The 8-OHdG concentrations in A549 cells transfected with sh-HMGB2 or sh-NC plus LPS treatment were assessed by ELISA. G Western blot analysis of the autophagy-related proteins in A549 cells transfected with sh-HMGB2 or sh-NC plus LPS treatment. H The concentrations of TNF-α, IL-1β and IL-6 in A549 cells transfected with sh-HMGB2 or sh-NC plus LPS treatment were assessed by ELISA. I The expression level of HMGB2 in A549 cells after LPS induction and the addition of PS600125 (20 μm/L) was detected by RT-qPCR. J HMGB2, JNK, p-JNK and β-actin protein levels in LPS induced A549 cells or LPS induced and PS600125 treated cells were assessed by western blot. K The effect of LPS treatment or LPS plus PS600125 treatments on A549 cell apoptosis was assessed by flow cytometry. L The Fluorescent probe was used to detect ROS level in LPS induced A549 cells or LPS-treated and PS600125 treated cells. M ELISA detected the concentrations of 8-OHdG in LPS induced A549 cells or LPS induced and PS600125 treated cells. N Western blot analysis of the autophagy-related proteins in LPS induced A549 cells or LPS induced and PS600125 treated cells. O The concentrations of TNF-α, IL-1β and IL-6 in LPS induced A549 cells or LPS induced and PS600125-treated cells were assessed by ELISA. n=3. *P < 0.05, ** P < 0.01, *** P < 0.001