Nature
June 1, 2024
Audrey L Warren, David Lankri, Michael J Cunningham et al.
74 citations
Psychedelic substances like LSD and psilocybin show potential for treating neuropsychiatric disorders, primarily acting through the serotonin 5-HT2A receptor. However, 5-HT1A also contributes to the effects of tryptamine hallucinogens, especially 5-MeO-DMT from Colorado River toad toxin. Using cryo-EM structures, medicinal chemistry, and mouse behavior, researchers mapped how 5-MeO-DMT engages 5-HT1A. They characterized molecular determinants of signaling potency, efficacy, and selectivity at both 5-HT1A and 5-HT2A. A 5-HT1A-selective analogue of 5-MeO-DMT lacked hallucinogenic effects but retained anxiolytic-like and antidepressant-like activity in socially defeated animals, uncovering molecular aspects that may aid developing new neuropsychiatric medications.
Biological psychiatry
March 28, 2025
Astrid M Cardona-Acosta, Lyonna F Parise, Carlos A Bolaños-Guzmán et al.
2 citations
Stress-induced disorders such as depression, anxiety, PTSD, and postpartum depression are increasingly common, yet current treatments are limited. This review examines ketamine as a potential preventive treatment, summarizing preclinical and clinical findings on (R,S)-ketamine and its metabolites (2R,6R)- and (2S,6S)-hydroxynorketamine. It explores underlying mechanisms involving brain regions, circuits, and glutamatergic, dopaminergic, serotonergic, and inflammatory processes. The review also notes limitations including age- and sex-specific efficacy, adverse effects, and legal and ethical concerns. Future research directions and clinical integration are discussed. The literature underscores the need for further study to weigh ketamine's benefits and risks as a prophylactic.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
June 1, 2026
Trevonn M Gyles, Eric M Parise, Molly Estill et al.
Treatment-resistant depression (TRD) affects about one-third of people with major depressive disorder, but its molecular basis is unclear. In a mouse model, chronic social defeat stress was followed by sequential treatment with fluoxetine and ketamine, allowing classification into antidepressant-responsive and non-responsive animals. RNA sequencing of the nucleus accumbens and prefrontal cortex revealed distinct transcriptional signatures. Prior fluoxetine exposure primed some mice for molecular and behavioral response to ketamine, but this priming was absent in non-responders, indicating that resistance stems not from treatment failure alone but from a lack of adaptive molecular priming. Gene co-expression network analysis identified modules linked to stress susceptibility and antidepressant resistance, offering insight into gene networks underlying TRD.