Conclusion
Our study indicates that CGA and CP extracts prevented depressive behavior and thereby have potential as natural antidepressants.
Results
Depression-like phenotypes were induced in mice by daily injection of stress hormone for 1-2 weeks. The brains of these animals exhibited reduced brain-derived neurotrophic factor expression and increased astrocytic hypertrophy, which are typical markers of depression in animal models. Stress hormone injection 1) upregulated monoamine oxidase B (MAOB) expression and 2) reduced spine numbers along neuronal dendrites, which indicates synaptic depression. The oral administration of CGA (30 mg kg-1 ) or CP (300 mg kg-1 ) prevented MAOB activation following reactive oxygen species (ROS) production and had an ameliorative effect on depressive behavioral tests (e.g., tail suspension and forced swim tests). In vitro assays performed on cultured C8-D1A cells revealed that CGA and CP inhibited MAOB activity and ROS production.