Studies have shown that during diabetes the DNA binding ability of Nrf2 is significantly reduced in retinal cells, and in contrast, the binding between Nrf2 and its inhibitor, Kelch like-ECH-associated protein 1 (Keap1) is increased resulting in enhanced Nrf2 degradation and decreased Nrf2 translocation to the nucleus [193, 194]. This evidence concerns the gene NFE2L2 and diabetes mellitus.