In a previous study, 30-day treatment with paeoniflorin (20 mg/kg, i.p.)was shown to reverse CUS-induced depression-like behaviors in mice by increasing BDNF and postsynaptic density protein 95 (PSD-95) expression and dendritic spine density (Liu et al., 2019) (Figure 6). This evidence concerns the gene BDNF and depressive symptom measurement.