Nelumbo nucifera Gaertn Stems (Hegeng) Improved Depression Behavior in CUMS Mice by Regulating NCAM and GAP-43 Expression

BACKGROUND: Nelumbo nucifera Gaertn stem (Hegeng [HG]) is a traditional Chinese medicine that is used to treat mental symptoms in East Asia. However, scientific evidence is generally lacking to support this traditional claim. Aim of the Study. This study's aim is to investigate the antidepression effect of HG and to further explore the possible molecular mechanisms that are involved in its actions. Materials and Methods. HG aqueous extract was administered intragastrically for 21 days after the chronic unpredictable mild stress (CUMS) procedure, and its effect on memory, learning, and emotion was assessed using animal behavioral tests. HG aqueous extract was characterized using HPLC. Immunofluorescence was used to measure the neural cell-adhesion molecule (NCAM) and growth-associated protein-43 (GAP-43) expression. RESULTS: Depression-like behaviors increased in the CUMS group compared with the control (CON) group, while they were reduced in the high-dose HG (H-HG) and fluoxetine (FLU) groups (p < 0.05). Additionally, NCAM and GAP-43 expression was reduced in the CUMS group compared with the CON group, but it increased in the H-HG and FLU groups (p < 0.05). CONCLUSIONS: These findings show the potential antidepressant effects of HG through mechanisms involving regulation of NCAM and GAP-43. This provides a new theoretical basis for its potential application as an antidepressant-like agent.