NeuroImage
July 12, 2017
Candace R. Lewis, Katrin H. Preller, Rainer Kraehenmann et al.
105 citations
Psilocybin, a hallucinogen, significantly enhances cerebral blood flow in key brain regions. In a study involving 30 participants, cerebral perfusion increased by 22% in the insula and 18% in the anterior cingulate cortex after psilocybin administration. This neurophysiological effect highlights its potential therapeutic applications in internal medicine and psychology. By influencing neurotransmitter receptor activity, psilocybin may alter behavior and emotional processing, suggesting exciting avenues for drug studies focused on psychedelics and their chemical synthesis from alkaloids.
Frontiers in Psychiatry
February 6, 2023
Candace R. Lewis, Joseph Tafur, Sophie Spencer et al.
29 citations
Epigenetic changes in hypothalamic-pituitary-adrenal (HPA) axis genes may predict successful psychotherapy for post-traumatic stress disorder (PTSD). In a pilot sub-study of a Phase 3 clinical trial, 23 participants (16 receiving MDMA-assisted therapy, 7 receiving placebo with therapy) provided saliva samples. Methylation at 259 CpG sites across three HPA genes (CRHR1, FKBP5, NR3C1) was measured before and after treatment. Methylation changes across both groups significantly predicted symptom reduction on 37 of the sites, with two surviving false discovery rate correction. The MDMA group showed greater methylation change on one NR3C1 site compared to placebo. Therapy-related PTSD symptom improvements may be linked to DNA methylation changes in HPA genes, and such changes may be larger with MDMA-assisted therapy.
Biomedicines
February 18, 2020
Candace R. Lewis, Katrin H. Preller, B. Blair Braden et al.
27 citations
Psilocybin, the psychoactive compound in psilocybe mushrooms, primarily affects serotonin 2A receptors, which are highly expressed in the cingulate cortex. In healthy adults (n = 55) given oral psilocybin at low (0.160 mg/kg) or high (0.215 mg/kg) doses, greater thickness of the rostral anterior cingulate predicted higher subjective ratings on emotional sub-scales of the Five-Dimensional Altered State of Consciousness questionnaire, after controlling for sex and age. The caudal and posterior cingulate did not show this effect. These findings suggest that individual differences in brain structure, specifically cingulate cortex thickness, contribute to the wide variability in subjective psychedelic experiences, extending the traditional set and setting hypothesis.
Research Square
November 5, 2025
Sarah E. Mennenga, Toni J. Hanson, Moira G. Semple et al.
2 citations
Psilocybin reverses age-related behavioral and epigenetic alterations in aged mice. Male and female C57BL/6 mice (11 months old) received two doses of psilocybin (1mg/kg) or saline one week apart. Psilocybin improved learning and memory in females and reduced depressive-like behavior across sexes. Genome-wide DNA methylation profiling in the prefrontal cortex and hippocampus revealed widespread, sex- and region-specific effects, with the right hippocampus of females showing the most extensive gene-level changes. Differentially methylated loci were enriched for pathways related to synaptic organization, axon guidance, and neuroimmune signaling.
bioRxiv Preprint Server
July 3, 2025
Moira G. Semple, Sarah E. Mennenga, Ryan Smith et al.
1 citation
preprint
Psychedelic compounds like ketamine and MDMA induce widespread DNA methylation changes in brain-enriched genes, with ketamine altering 1,210 CpG sites and MDMA affecting 2,074 CpG sites. These changes occur in genes involved in neuroplasticity, immune regulation, and mental processes, with overlapping effects in genes such as PTPRN2 and SHANK2. The findings suggest shared epigenetic mechanisms through which psychedelics may drive increased neuroplasticity and produce lasting molecular changes relevant to neuroimmune function and psychiatric health.
Translational Psychiatry
July 11, 2026
Moira G. Semple, Sarah E. Mennenga, Ryan Smith et al.
Ketamine and MDMA, compounds known as psychoplastogens, show therapeutic potential for mood and trauma-related disorders, but their molecular mechanisms are not fully understood. In a study analyzing blood samples from 20 ketamine-treated participants and saliva samples from 16 MDMA-treated participants, DNA methylation changes were examined using a Brain-Epigenome-Wide Association Study targeting brain-relevant genes. Ketamine was associated with 405 significantly altered genes and 169 functional networks, while MDMA was linked to 346 altered genes and 183 networks. Both compounds converged on pathways related to neuroplasticity and neuroimmune regulation, suggesting they induce peripheral epigenetic changes that engage molecular pathways relevant to psychiatric health.