Loading
Tryptophan and Brain Disorders · Journal article
The International Journal of Neuropsychopharmacology · September 1, 2026
Raises a question worth testing. It does not answer one.
This is an in vitro mechanistic study showing that psilocin dose- and time-dependently suppresses interferon-α, interferon-β, TNF-α, and IDO1 mRNA expression in Poly I:C-stimulated human PBMCs at concentrations corresponding to clinical psilocybin doses. The findings are exploratory and do not establish clinical relevance, causality in vivo, or the functional significance of these changes for mood, immunity, or clinical efficacy.
In vitro single-arm experimental study. Peripheral blood mononuclear cells from healthy donors; setting and eligibility criteria not specified. Intervention: Psilocin (0.03–30 μM) added at 2, 6, or 24 hours post-Poly I:C stimulation. Compared with: Poly I:C stimulation alone (no psilocin).
Psilocin at 0.1 μM (physiologically relevant after 25 mg psilocybin) significantly decreased IFN-α, IFN-β, TNF-α, and IDO1 expression when added 2 or 6 hours post-Poly I:C stimulation Psilocin treatment at 24 hours post-stimulation reduced only IFN-β and IDO1 levels, demonstrating time-dependent effects Poly I:C (10–80 μg/mL) induced robust upregulation of IFN-α, IFN-β, IL-1β, IL-6, and IDO1 mRNA expression in PBMCs
Safety was not reported in the material analysed. Check the source before drawing any conclusion about harm.
This finding raises the hypothesis that psilocin's clinical effects in depression and PTSD may involve peripheral immune modulation; however, the in vitro setting, absence of patient data, and unclear functional consequences prevent any change to clinical practice. Future work must establish whether these immune changes occur in vivo, persist with standard dosing, and correlate with clinical outcomes.
In vitro mechanistic study in healthy donor cells using a viral mimetic; demonstrates psilocin's immunomodulatory effects on gene expression but lacks clinical outcome data, disease-relevant populations, or validation in vivo.
As stated by the source record.
Quoted from the source exactly as published.
This finding raises the hypothesis that psilocin's clinical effects in depression and PTSD may involve peripheral immune modulation; however, the in vitro setting, absence of patient data, and unclear functional consequences prevent any change to clinical practice. Future work must establish whether these immune changes occur in vivo, persist with standard dosing, and correlate with clinical outcomes.
Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.
Abstract Background Serotonergic psychedelics have recently re-emerged as promising therapeutic agents in psychiatry, showing positive outcomes in clinical trials for treatment-resistant depression, major depression, and PTSD. However, their effects on the immune system are poorly characterized. It remains unclear whether these compounds exert immunomodulatory effects that contribute to their behavioural and clinical efficacy while maintaining a favourable safety profile. Among these agents, psilocybin, metabolized in vivo to the active compound psilocin, has received the most clinical attention. Aims & Objectives This study aimed to investigate whether psilocin influences antiviral immune signalling in human peripheral blood mononuclear cells (PBMCs) stimulated with the viral mimetic polyinosinic:polycytidylic acid (Poly I:C). Specifically, it sought to determine the timing and extent of psilocin’s immunomodulatory effects on cytokine and interferon responses. Method PBMCs from healthy donors were isolated, cultured, and stimulated with Poly I:C (10–80 μg/mL) for 2–72 hours to activate aTLR3-mediated inflammatory, anti-viral response. mRNA expression levels of IFN-α, IFN-β, IL-1β, IL-6, and IDO1 were quantified by real-time quantitative PCR (RT-qPCR). Cell number and viability were assessed via trypan blue exclusion. Psilocin (0.03–30 μM) was added at 2, 6, or 24 hours after Poly I:C stimulation (40 μg/mL for 24 hours), and effects on cytokine gene expression were evaluated. Results Poly I:C stimulation induced robust upregulation of IFN-α, IFN-β, IL-1β, IL-6, and IDO1 mRNA expression. At a concentration of 0.1 μM, Psilocin treatment at 2 or 6 hours post-stimulation significantly decreased IFN-α, IFN-β, TNF-α, and IDO1 expression, whereas treatment at 24 hours post-stimulation reduced only IFN-β and IDO1 levels. The lowest effective psilocin concentration (0.1 μM) corresponded to physiologically relevant plasma levels following oral administration of a standard 25 mg psilocybin dose. Discussion & Conclusions These findings indicate that psilocin exerts time-dependent immunomodulatory effects on antiviral signalling pathways in human PBMCs. Direct immunomodulation suggests that psilocin is not only capable of acting in the brain but also of influencing peripheral immune signalling. Notably, the lowest concentration tested (0.1 μM) corresponds to physiologically relevant plasma levels following oral administration of a standard 25 mg psilocybin dose. Future investigations will evaluate psilocin’s effects on immune activation induced by other stimuli, including bacterial lipopolysaccharide (LPS), and determine whether related serotonergic psychedelics such as dimethyltryptamine (DMT) and lysergic acid diethylamide (LSD) produce comparable immunomodulatory activity. Immune cells express serotonin receptors including 5-HT2A, so modulation of IFN responses supports a functional role for serotonergic signalling in innate immunity. It will also be important to establish the mechanisms by which serotonergic psychedelics produce these immunomodulatory effects. Moreover, changes in interferon signalling could be one pathway linking psychedelic exposure to downstream effects on mood, inflammation and behaviour.
Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.