Baicalin regulates depression behavior in mice exposed to chronic mild stress via the Rac/LIMK/cofilin pathway

[Display omitted] •The antidepressant effect of baicalin on chronic unpredictability stress mice was confirmed.•The antidepressant effect of baicalin was mediated by improved neuroplasticity.•Baicalin improved neuroplasticity by affecting the expressions of BDNF, thereby activating the Rac-Limk-cofilin pathway. Depression is a common disease that endangers people’s physical and mental health. Traditional Chinese medicine has advantages in treating the emotional and cognitive symptoms of depressive disorders. To study the effects of baicalin on the behavior and to clarify the underlying mechanism through evaluation of the Rac1-LIMK1-cofilin pathway. A chronic mild stress (CMS) model of depression was used. Baicalin was administered to the mice for the intervention, and the positive control group was treated with fluoxetine. Behavioral tests were conducted to observe the degree of depressive disorders. Synaptophysin (SYP), postsynaptic density protein-95 (PSD95), brain-derived neurotrophic factor (BDNF), tyrosine kinase receptors (TrkB), Rac1 and cofilin expression was determined using Western blot analysis, and mRNA was quantified using real-time PCR. Mice in the CMS group showed an increase in depression-like behavior (p