In addition, lipocalin 2 (Lcn2) was upregulated in PVT of mice with depressive behavior induced by dextran sulfate sodium (DSS), and the depressive behavior was reduced when Lcn2 was silenced, which indicated that the increase of Lcn2 in PVT was an important pathway of depression induced by DSS (155). This evidence concerns the gene LCN2 and major depressive disorder.