Psilocybin restores behavioral and neuroplastic deficits induced by chronic stress in rats.
Agnieszka Bysiek, Izabela Szpręgiel, Adam Wojtas, Marzena Maćkowiak, Agnieszka Wawrzczak-Bargieła, Monika Leśkiewicz, Ewa Trojan, Katarzyna Kamińska, Weronika Kumorek, Wiktor Bilecki, Krystyna Gołembiowska
Progress in Neuro-Psychopharmacology and Biological Psychiatry June 20, 2026 DOI: 10.1016/j.pnpbp.2026.111710 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Stressed rats |
| Intervention | Psilocybin |
| Dose | 0.6 mg/kg, s.c., 7 days apart |
| Topics | Neuroplasticity Psilocybin |
| Keywords | Behavior |
| Key findings | Psilocybin reversed anhedonia, produced antidepressant and anxiolytic effects, and induced hippocampal neurogenesis in stressed rats. |
Abstract
Psychedelics have emerged as a promising novel therapeutic approach for major depressive disorder (MDD). Altered activity and structural atrophy of the prefrontal cortex, hippocampus, and limbic structures are associated with depressive disorders. Psilocybin may reverse the loss of synaptic connections and restore the function of these brain regions. In this study, we investigated the effects of psilocybin on rat behavior, hippocampal neurogenesis, expression level of brain-derived neurotrophic factor (BDNF) and hypothalamic-pituitary-adrenal (HPA) axis activity. Psilocybin administered in two doses (0.6 mg/kg, s.c., 7 days apart) reversed anhedonia in stressed rats, produced antidepressant-like effects in the forced swim test (FST), and exerted anxiolytic activity in the light/dark box (LDB), elevated plus maze (EPM), and open field (OF) tests in stressed animals. Psilocybin induced hippocampal neurogenesis as evidenced by increasing the number of BrdU-positive cells (an exogenous marker of cell proliferation and survival), DCX-positive cells (a marker of immature neurons), and Ki-67-positive cells (an endogenous marker of cell proliferation) in stressed animals. Stress-induced reductions in BDNF expression levels appeared to be associated with normalization of HPA axis activity. These findings underscore the role of psilocybin-induced neuroplasticity in the antidepressant and anxiolytic mechanisms of psychedelics.
Comparable studies
Other preclinical and animal studies on psilocybin, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Psilocybin induces rapid and persistent growth of dendritic spines in frontal cortex in vivo Mice | 2021 | Observational cohort | |
| Harnessing psilocybin: antidepressant-like behavioral and synaptic actions of psilocybin are independent of 5-HT2R activation in mice Mice | 2021 | Experimental study | |
| Psychedelics reopen the social reward learning critical period Mice | 2023 | Experimental study in mice | |
| Correlation between the potency of hallucinogens in the mouse head-twitch response assay and their behavioral and subjective effects in other species. C57BL/6J mice | 2020 | Experimental study with dose-response experiments | |
| Effects of psilocybin on hippocampal neurogenesis and extinction of trace fear conditioning Mice | 2013 | Experimental study |
Citations in the library
Cites 35
- Psilocybin with psychological support for treatment-resistant depression: an open-label feasibility study. The Lancet Psychiatry May 17, 2016
- Trial of Psilocybin versus Escitalopram for Depression New England Journal of Medicine April 14, 2021
- Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder JAMA Psychiatry November 4, 2020
- Single-Dose Psilocybin for a Treatment-Resistant Episode of Major Depression. New England Journal of Medicine November 3, 2022
- Psilocybin with psychological support for treatment-resistant depression: six-month follow-up. Psychopharmacology November 8, 2017
and 30 more in the library