Hominis Placenta modulates PTSD-like behaviors in SPSS-induced PTSD mice: Regulating energy metabolism and neuronal activity.

The symptoms of post-traumatic stress disorder (PTSD) include re-experiencing trauma, avoidance behaviors, negative alterations in cognition and mood. However, the underlying molecular mechanisms are unclear. Dysfunction of hypothalamic-pituitary-adrenal axis (HPA-axis) and dysregulation of glutamatergic and GABAergic systems were shown during PTSD. Therefore, regulating hormonal change or glutamate energy metabolism are considered as a therapeutic approach to alleviate this condition. Herbal medicine may be effective in treating PTSD due to its ability to target multiple underlying mechanisms with various compounds. Hominis placenta (HP) is a traditional medicine widely used in East Asia for various conditions. However, the effect on PTSD has not been clarified. We aimed to investigate the effects of HP treatment in single-prolonged stress with shock (SPSS)-induced PTSD mice and explore its possible mechanisms. HP treatment at ST36 acupoints, combined with herbal medicine and acupuncture point stimulation, was applied three times/week for 2 weeks. HP treatment effectively alleviated anxiety and cognitive decline in SPSS-induced PTSD mice, as detected by Open field and the Y-maze test. Additionally, HP decreased the corticosterone levels and proinflammatory cytokines in the serum, modulated brain energy metabolism, and inhibited glutamate excitotoxicity, while regulating neuronal activity through modulating brain-derived neurotrophic factor (BDNF) levels, as demonstrated by western blot and immunohistochemistry, and flow cytometry analyses. These findings reveal that HP treatment effectively alleviates PTSD-like behaviors by regulating energy metabolism and neuronal activity though modulation of the HPA-axis and BDNF levels in PTSD mice, indicating that HP treatment is a promising therapeutic approach for PTSD.