ESR1 and retinal degeneration: For example, 17β-estradiol upregulates the Nrf2 pathway via activation of the estrogen receptor to suppress light-induced rat retinal degeneration (Zhu et al., 2015), and S-(−)equol induces endothelial cell survival by activation of the Nrf2 pathway via ERα and ERβ (Zhang et al., 2013).