Formononetin attenuates corticosterone-induced depressive-like behaviors and neuronal damage via ERα/ERK-CREB-BDNF signaling pathway

ObjectivesFormononetin (FMN) is known for its significant neuroprotective effects, this study aims to investigate the antidepressant potential and underlying mechanisms of FMN.‌MethodsAntidepressant efficacy was evaluated in corticosterone (CORT)-induced depression models. In vivo, CORT-exposed mice received FMN to assess behavioral and hippocampal changes (dendritic spine density, synaptic markers: MAP-2/GAP-43). In silico, network pharmacology and molecular docking predicted FMN’s binding affinity and enriched pathways. In vitro, HT22 cells pretreated with FMN (10 μM, 6 h) were subjected to CORT injury, with mechanistic validation via ERα antagonist (MPP) and ERK inhibitor (PD98059).Key findingsFMN alleviated depressive-like behaviors and preserved hippocampal integrity in mice. Bioinformatics analysis revealed FMN’s strong binding to ER subtypes and enrichment in estrogen/MAPK pathways. In vitro, FMN pretreatment activated the ERK-CREB-BDNF axis in CORT-injured HT22 cells, enhancing neuronal survival and synaptic function. The activation was ERα/ERK-dependent, as evidenced by the abolition of protective effects following pharmacological inhibition with MPP (ERα antagonist) or PD98059 (ERK inhibitor). Concomitantly, in vivo FMN treatment restored hippocampal p-ERK/ERK ratios in mice, directly corroborating the ERK-CREB-BDNF pathway activation and highlighting its efficacy in reversing CORT-induced signaling deficits.ConclusionFMN exerts antidepressant effects via ERα-mediated neurotrophic signaling (ERK-CREB-BDNF), offering a mechanistic foundation for natural antidepressant development.