TNF and major depressive disorder: Key targets including AKT1, TNF, IL-6, and EGFR were identified as central to YHD's action.<h4>Discussion</h4>YHD alleviates PCPA-induced depression-like behaviors in mice by modulating 5-HT levels, correcting metabolic imbalances in tryptophan and riboflavin pathways, and regulating neuroinflammation, neurotransmitter systems, and cellular signaling via targets such as AKT1 and TNF.