The variable concentrations of ERα and ERβ may play a distinct role in the modulation of ROS generation. The mechanism of action of selective ER modulator (SERM) tamoxifen and pure anti-estrogen ICI182780 that bind to both ERα and ERβ shed some light on the overall knowledge about the role of SERMs in affecting the disorders like cancers [30]and neurological disorders like Alzheimer's disease, Parkinsonism etc. [31]