Corticosterone-induced neuronal dysfunction in hippocampal cultures: a novel in vitro model for stress-related...

Major depression is associated with hippocampal pathology induced by prolonged exposure to stress hormones; yet, research predominantly utilizes animal models, which entail considerable costs, time, and translational constraints. While various studies have been conducted to investigate the neurotoxic effects of CORT, these research efforts have frequently been dispersed, concentrating on single endpoints or making use of immortalized cell lines that are less relevant. As a result, these studies have not adequately represented the integrated nature of neuronal dysfunction. To address this, we established and verified a complete, multi-parametric in vitro model involving the use of primary hippocampal neurons that were treated with corticosterone. This study effectively incorporates various aspects of stress-induced neuropathology. Our integrated approach demonstrates that corticosterone treatment resulted in concentration-dependent reductions in neuronal viability, increased reactive oxygen species production, disrupted mitochondrial membrane potential, attenuated neurite outgrowth, and impaired neuronal polarization. Furthermore, corticosterone significantly downregulated expression of key neurogenic markers (BDNF, TrkB, and DCX), mirroring the neurotrophic deficits observed in depression. The model demonstrated predictive validity through its response to fluoxetine, which ameliorated neuronal differentiation impairments and restored neurotrophic signaling. This primary hippocampal neuron-corticosterone system offers researchers an efficient platform for mechanistic investigations and preliminary screening of potential antidepressant compounds, potentially facilitating more targeted subsequent in vivo studies while reducing animal usage. By replicating multiple aspects of stress-induced neuronal dysfunction, it represents a valuable tool for depression research and therapeutic development.