Frontiers in Psychiatry
May 14, 2024
Zijia Yu, Lisa Burback, Olga Winkler et al.
38 citations
A scoping review of 24 articles found that four psychedelic drugs—ayahuasca, psilocybin, LSD, and the entactogen MDMA—consistently alter brain functional connectivity in healthy individuals. The drugs decreased connectivity within the default mode network and increased sensory and thalamocortical connectivity. These neurophysiological changes correlated with subjective experiences such as altered consciousness, mood elevation, and mystical experiences, suggesting a brain network basis for the drugs' psychological effects. The review provides a potential neural mechanism for psychedelics' subjective effects but notes that direct clinical evidence is needed to advance therapeutic outcomes.
Research Square
May 6, 2025
Zitong Wang, Brett Robbins, R. L. Zhuang et al.
In an animal model of treatment-resistant depression, psilocybin produced a significant and lasting reduction in behavioral despair and cognitive impairment. The compound increased thyroid-stimulating hormone levels without altering the hypothalamic-pituitary-adrenal axis, countering stress-induced TSH reductions that may serve as a proxy marker of therapeutic response. Changes in cannabinoid receptor type I after psilocybin administration suggest possible modulation of the endocannabinoid system, though causal links remain unconfirmed. These findings highlight psilocybin's potential to treat treatment-resistant depression through targeting previously unexplored biological pathways.
The International Journal of Neuropsychopharmacology
February 1, 2025
Zitong Wang, Yanbo Zhang, Xin‐min Li
Psilocybin at 1.0 mg/kg reduced depressive-like behavior and cognitive impairment in stressed Wistar rats but not in treatment-resistant Wistar-Kyoto rats. It downregulated ACTH and corticosterone in Wistar rats, upregulated TSH and melatonin in both strains, and increased BDNF levels in blood and brain regions including the prefrontal cortex, amygdala, hippocampus, and hypothalamus. Psilocybin also upregulated CB1R and TrkB, activated Akt, ERK, and mTOR pathways, and increased 2-AG levels across brain regions. The findings suggest psilocybin mitigates stress-induced HPA axis dysregulation by modulating BDNF signaling mediated by the endocannabinoid system, offering insights into antidepressant mechanisms.