Nrf2 expression and GSH concentrations were significantly reduced in the Diabetes group compared with Controls (all p < 0.001), whereas spermidine treatment significantly increased both parameters compared with Diabetes (p < 0.01; p < 0.001, respectively), although values remained below those of Controls (p < 0.05; p < 0.01, respectively). Here, NFE2L2 is linked to diabetes mellitus.