Heterogeneities of Site-Specific N‑Glycosylation in the Hippocampus of Depression-like Behavior Models in Mice Induced by Acute Stress and Chronic Stress

It is well established that acute and chronic stress
contributes to the onset and progression of depression, but the underlying
mechanisms have not been elucidated. Here an integrated N-glycoproteomic
and proteomic analysis was performed to investigate heterogeneities
of glycoprotein and site-specific glycosylation between the hippocampi
of control, acute stress-affected (AS), and chronic mild stress-affected
(CMS) mice. 1063 unique intact N-glycopeptides, 116 N-glycan compositions,
and 512 glycosylation sites were identified. CMS and AS had significant
effects on glycosylation. CMS reduced multiantenna glycosylation (N8H8
and N6H5F1S1) more strongly, while AS reduced multiantenna glycosylation
(N5H3F1) more strongly. CMS inhibited high-mannose synthesis with
high polymerization (N2H9 and N2H8), while AS inhibited high-mannose
synthesis with low polymerization (N2H6, H2H5). Furthermore, 26 and
39 glycosylation-related genes (GRGs) were identified in the AS and
CMS groups, separately. Functional enrichment analysis for GRGs in
the AS and CMS groups exhibited that the up-regulated functions were
leading edge membrane and cell adhesion molecule binding; meanwhile,
the down-regulated functions were cAMP signaling pathways. Finally,
tSNE analysis based on ScRNA-seq revealed that core GRGs were highly
expressed in astrocytes. All of these findings improve our understanding
of glycosylation in stress-related depression, providing valuable
data resources for depression pathogenesis exploration and novel therapeutic
target discovery.