CQ, being a chaperone able to trespass the BBB, rather than acting as metal chelator to remove metal ions, can redistribute zinc to brain post-synaptic targets leading to events such as TrkB activation and pro-BDNF conversion with beneficial effects on cognitive function in amyloid protein pre-cursor transgenic mice, AD model, and ZnT3 KO mice (White et al., 2006). This evidence concerns the gene NTRK2 and Alzheimer disease.