This latter observation that appears not to be associated with an elevated level of serum corticosterone, is in agreement with a recent study relating that Sort1−/− mice displayed elevated anxiety-like behavior and that chronically stressed wild-type mice showed an increase in the sortilin expression in neocortex and hippocampus leading to an increased depression-like behavior (Ruan et al., 2016). Here, SORT1 is linked to major depressive disorder.