The PI3K/AKT/NRF2 Signaling Pathway Involved in the Improvement of CUMS-Induced Depressive-like Behaviors by Apigenin

Background/Objectives: Apigenin, a naturally occurring flavonoid, has shown promising antidepressant-like effects in previous studies. However, its precise mechanisms remain unclear. This study aims to investigate the underlying neurobiological mechanisms mediating the antidepressant effects of apigenin in chronic unpredictable mild stress (CUMS)-induced mice. Methods: The male mice were subjected to 4-week CUMS, with or without treatment, followed by behavioral testing. Network pharmacology analysis was employed to predict relevant signaling pathways. The mRNA and protein expression levels of the PI3K/AKT/NRF2 pathway were measured. Oxidative stress was assessed through the measurement of malondialdehyde, glutathione, and superoxide dismutase levels. Results: Apigenin significantly ameliorated CUMS-induced depression-like behaviors. The PI3K/AKT pathway may mediate the antidepressant properties of apigenin with both PI3K and AKT emerging as core target molecules. Apigenin restored the activity of the PI3K/AKT/NRF2 pathway and oxidative stress in the hippocampus downregulated by CUMS. Conclusions: The present study demonstrates that apigenin ameliorates depression-like behaviors in mice exposed to CUMS and mitigates oxidative stress in the hippocampus, which is associated with the PI3K/AKT/NRF2 signaling pathway.