Fig 2: Effect of DMF on oxidative stress on SHSY5Y cells in high glucose. (A) Representative Western blots of proteins extracted from SHSY5Y cells treated as indicated above the blots. Blots were probed with the indicated antibodies. ß-actin and laminin were used as loading controls. (B) Quantitative analyses of the blots revealed a significant decrease in HO-1 levels in the HG group compared to the CTL group. While 0.1 mM DMF did not affect HO-1 levels, 1 mM DMF prevented the HG-induced decrease in HO-1 levels. *** p < 0.001 vs. CTR; ### p < 0.001 vs. HG. (C) Quantitative analyses of the blots revealed a significant decrease in MnSOD levels following high glucose exposure. Notably, DMF prevented the decrease in MnSOD and increased MnSOD steady-state levels beyond the CTL group *** p < 0.001 vs. CTR; ## p < 0.01 vs. HG; ### p < 0.001 vs. HG. (D) Quantitative analyses of the blots revealed a significant decrease in catalase levels following high glucose exposure. Concentrations of 0.1 mM and 1 mM DMF significantly increased the expression of catalase compared to the HG group. *** p < 0.001 vs. CTR; ## p < 0.01 vs. HG; ### p < 0.001 vs. HG. (E) Quantitative analyses of the blots revealed a significant decrease in Nrf-2 levels following high glucose exposure. Concentrations of 0.1 mM and 1 mM DMF significantly increased the expression of Nrf-2 compared to HG group. *** p < 0.001 vs. CTR; # p < 0.05 vs. HG; ### p < 0.001 vs. HG. (F,G) GSH and ROMO1 levels in culture media were measured by ELISA. GSH levels were significantly reduced by high glucose exposure. A concentration of 0.1 mM DMF prevented such a decrease, however 1 mM DMF exacerbated the effects of high glucose on GSH levels. Glucose deprivation significantly increased ROMO1 levels; this increase was attenuated by DMF. In panel (B): p < 0.05 vs. CTR; ## p < 0.01 vs. HG. In panels (C–E): *** p < 0.001; ### p < 0.001 vs. HG. Data are representative of at least three independent experiments (n = 3). Statistical analysis was performed by One-way ANOVA, followed by multiple comparisons performed by Bonferroni’s test.