The DG is one of the earliest and most vulnerable hippocampal regions affected by AD pathology.[38] Moreover, substantial Aβ plaque accumulation has been reported in this area,[39] and astrocytes in the DG are actively involved in Aβ clearance through endocytosis and autophagy.[40] Based on these pathological and functional characteristics, we selected the DG as the injection site to maximize the therapeutic impact of Mt3 activation. The gene discussed is MT3; the disease is Alzheimer disease.