FIG. 4.

Sulforaphane-modulated Nrf2-Keap1 interactions in the transcription of phase II antioxidant enzymes. Sulforaphane has the ability to induce nuclear translocation of Nrf2 through the disruption of the Nrf2-Keap1 complex via the degradative loss of Keap1 via conformational changes. Specific modifications of Keap1 release Nrf2 from sequestration, promoting its nuclear translocation and activation. Activation of Nrf2 in the nucleus occurs through its heterodimerization with small Maf transcription factors to form a complex that binds to the antioxidant/electrophile response element (ARE/EpRE) that is found in the promoters of many phase II enzymes, ultimately leading to ARE-driven gene expression (and subsequent upregulation of phase II antioxidant enzymes).