New evidence piles up for the use of psychedelics in the fight against depression. Classical psychedelics seem to be longer-lasting in their effect than ketamine. And people can be fooled into thinking they are tripping, by carefully manipulating the setting.

A single psilocybin dose is associated with long-term increased mindfulness, preceded by a proportional change in neocortical 5-HT2A receptor binding

Authors: Martin Korsbak Madsen, Patrick MacDonald Fisher, Dea Siggaard Stenbæk, Sara Kristiansen, Daniel Burmester, Szabolcs Lehel, Tomas Páleníček, Martin Kuchař, Claus Svarer, Brice Ozenne & Gitte M. Knudsen

Published: 2 Mar 2020

One sentence summary: Long-term (3 months) follow-up of a single high dose of psilocybin confirms increased Openness (OCEAN), and finds mindfulness to be positively influenced and the latter correlated negatively with 5-HT2AR (serotonin) binding.

“A single dose of the serotonin 2A receptor (5-HT2AR) agonist psilocybin can have long-lasting beneficial effects on mood, personality, and potentially on mindfulness, but underlying mechanisms are unknown. Here, we for the first time conduct a study that assesses psilocybin effects on cerebral 5-HT2AR binding with [11C]Cimbi-36 positron emission tomography (PET) imaging and on personality and mindfulness. Ten healthy and psychedelic-naïve volunteers underwent PET neuroimaging of 5-HT2AR at baseline (BL) and one week (1W) after a single oral dose of psilocybin (0.2–0.3 mg/kg). Personality (NEO PI-R) and mindfulness (MAAS) questionnaires were completed at BL and at three-months follow-up (3M). Paired t-tests revealed statistically significant increases in personality Openness (puncorrected = 0.04, mean change [95%CI]: 4.2[0.4;∞]), which was hypothesized a priori to increase, and mindfulness (pFWER = 0.02, mean change [95%CI]: 0.5 [0.2;0.7]). Although 5-HT2AR binding at 1W versus BL was similar across individuals (p-uncorrected = 0.8, mean change [95%CI]: 0.007 [−0.04;0.06]), a post hoc linear regression analysis showed that change in mindfulness and 5-HT2AR correlated negatively (β [95%CI] = −5.0 [−9.0; −0.9], pFWER= 0.046). In conclusion, we confirm that psilocybin intake is associated with long-term increases in Openness and – as a novel finding – mindfulness, which may be a key element of psilocybin therapy. Cerebral 5-HT2AR binding did not change across individuals but the negative association between changes in 5-HT2AR binding and mindfulness suggests that individual change in 5-HT2AR levels after psilocybin is variable and represents a potential mechanism influencing long-term effects of psilocybin on mindfulness.”

Natural Psychoplastogens As Antidepressant Agents

Authors: Jakub Benko & Stanislava Vranková

Published: 5 March 2020

One sentence summary: Compounds (psychedelics, but also analogs) that increase plasticity in the brain, rapidly, can maybe treat depression better than antidepressants.

“Increasing prevalence and burden of major depressive disorder presents an unavoidable problem for psychiatry. Existing antidepressants exert their effect only after several weeks of continuous treatment. In addition, their serious side effects and ineffectiveness in one-third of patients call for urgent action. Recent advances have given rise to the concept of psychoplastogens. These compounds are capable of fast structural and functional rearrangement of neural networks by targeting mechanisms previously implicated in the development of depression. Furthermore, evidence shows that they exert a potent acute and long-term positive effects, reaching beyond the treatment of psychiatric diseases. Several of them are naturally occurring compounds, such as psilocybin, N,N-dimethyltryptamine [DMT], and 7,8-dihydroxyflavone. Their pharmacology and effects in animal and human studies were discussed in this article.“

More about psychoplastogens in this article.

Psychedelics, but Not Ketamine, Produce Persistent Antidepressant-like Effects in a Rodent Experimental System for the Study of Depression

Authors: Meghan Hibicke, Alexus N. Landry, Hannah M. Kramer, Zoe K. Talman & Charles D. Nichols

Published: 5 Mar 2020

One sentence summary: In rats, only ‘classical’ psychedelics had long-lasting effects (and had those without ‘therapy’), ketamine only had transient effects (<5 weeks).

“Psilocybin shows efficacy to alleviate depression in human clinical trials for six or more months after only one or two treatments. Another hallucinogenic drug, esketamine, has recently been U.S. Food and Drug Administration (FDA)-approved as a rapid-acting antidepressant. The mechanistic basis for the antidepressant effects of psilocybin and ketamine appear to be conserved. The efficacy of these two medications has not, however, been directly compared either clinically or preclinically. Further, whether or not a profound subjective existential experience is necessary for psilocybin to have antidepressant effects is unknown. To address these questions, we tested psilocybin, lysergic acid diethylamide (LSD), and ketamine in a rat model for depression. As in humans, a single administration of psilocybin or LSD produced persistent antidepressant-like effects in our model. In contrast, ketamine produced only a transient antidepressant-like effect. Our results indicate that classic psychedelics may have therapeutic efficacy that is more persistent than that of ketamine, and also suggest that a subjective existential experience may not be necessary for therapeutic effects.”

Tripping on nothing: placebo psychedelics and contextual factors

Authors: Jay A. Olson, Leah Suissa-Rocheleau, Michael Lifshitz, Amir Raz & Samuel P. L. Veissiere

Published: 7 Mar 2020

One sentence summary: In a highly-suggestible environment (setting), participants (61%) who took a placebo though they felt (some) effects of the drug.

“Rationale Is it possible to have a psychedelic experience from a placebo alone? Most psychedelic studies find few effects in the placebo control group, yet these effects may have been obscured by the study design, setting, or analysis decisions. Objective We examined individual variation in placebo effects in a naturalistic environment resembling a typical psychedelic party.
Methods Thirty-three students completed a single-arm study ostensibly examining how a psychedelic drug affects creativity. The 4-h study took place in a group setting with music, paintings, coloured lights, and visual projections. Participants consumed a placebo that we described as a drug resembling psilocybin, which is found in psychedelic mushrooms. To boost expectations, confederates subtly acted out the stated effects of the drug and participants were led to believe that there was no placebo control group. The participants later completed the 5-Dimensional Altered States of Consciousness Rating Scale, which measures changes in conscious experience.
Results There was considerable individual variation in the placebo effects; many participants reported no changes while others showed effects with magnitudes typically associated with moderate or high doses of psilocybin. In addition, the majority (61%) of participants verbally reported some effect of the drug. Several stated that they saw the paintings on the walls “move” or “reshape” themselves, others felt “heavy. . . as if gravity [had] a stronger hold”, and one had a “come down” before another “wave” hit her.
Conclusion Understanding how context and expectations promote psychedelic-like effects, even without the drug, will help researchers to isolate drug effects and clinicians to maximise their therapeutic potential.“

Updating the dynamic framework of thought: Creativity and psychedelics

Authors: Manesh Girn, Caitlin Mills, Leor Roseman, Robin L. Carhart-Harris, Kalina Christoff

Published: 8 Mar 2020

One sentence summary: In an updated model, the authors say the psychedelic state may facilitate creative generation.

“Contemporary investigations regard creativity as a dynamic form of cognition that involves movement between the dissociable stages of creative generation and creative evaluation. Our recently proposed Dynamic Framework of Thought (Christoff et al., 2016) offered a conceptualization of these stages in terms of an interplay between sources of constraint and variability on thought. This initial conceptualization, however, has yet to be fully explicated and given targeted discussion. Here, we refine this framework’s account of creativity by highlighting the dynamic nature of creative thought, both within and between the stages of creative generation and evaluation. In particular, we emphasize that creative generation in particular is best regarded as a product of multiple, varying mental states, rather than being a singular mental state in and of itself. We also propose that the psychedelic state is a mental state with high potential for facilitating creative generation and update the Dynamic Framework of Thought to incorporate this state. This paper seeks to highlight the dynamic nature of the neurocognitive processes underlying creative thinking and to draw attention to the potential utility of psychedelic substances as experimental tools in the neuroscience of creativity.”

Use of Benefit Enhancement Strategies among 5-Methoxy-N,N-Dimethyltryptamine (5-MeO-DMT) Users: Associations with Mystical, Challenging, and Enduring Effects

Authors: Rafael Lancelotta & Alan K. Davis

Published: 10 Mar 2020

One sentence summary: Not drinking, meditation, support, and shamanistic rituals (benefit enhancement strategies) helped users that were surveyed (n = 515) getting the most out of the DMT experience.

“5-Methoxy-N,N-Dimethyltryptamine (5-MeO-DMT) is a potent, fast-acting psychedelic. Anecdotal reports from 5-MeO-DMT users suggest that they employ a variety of benefit enhancement (BE) strategies aimed to increase positive effects and decrease any potential challenging effects of the substance, but no empirical study has investigated this claim. We examined the prevalence of BE strategy use using secondary data from a survey of 5-MeO-DMT users (n = 515; M_age = 35.4, SD = 11.7; Male = 79%; White/Caucasian = 86%). Results indicated that BE strategy use was common in this sample. As a secondary aim, we assessed whether the use of BE strategies was associated with acute subjective (i.e., mystical-type, challenging) and persisting effects of 5-MeO-DMT among a subset of respondents who reported using 5-MeO-DMT once in their lifetime (n = 116). Results showed that the use of several BE strategies were associated with significantly more intense mystical-type effects and enduring beliefs about the personal meaning and spiritual significance of their experience, and some BE strategies were associated with less intense or challenging experiences. Data suggests that BE strategies are commonly used, and that the use of BE strategies may be associated with increases in positive mystical-type and enduring effects. The causal influence of BE strategies on acute/persisting effects of 5-MeO-DMT should be examined in longitudinal research.”

Reviewing the Potential of Psychedelics for the Treatment of PTSD

Authors: Erwin Krediet, Tijmen Bostoen, Joost Breeksema, Annette van Schagen, Torsten Passie & Eric Vermetten

Published: 14 Mar 2020

One sentence summary: Overview of where we stand in regard to PTSD and psychedelics (in the widest sense) as a possible novel treatment option.

“There are few medications with demonstrated efficacy for the treatment of posttraumatic stress disorder (PTSD). Treatment guidelines have unequivocally designated psychotherapy as a first line treatment for PTSD. Yet, even after psychotherapy, PTSD often remains a chronic illness, with high rates of psychiatric and medical comorbidity. Meanwhile, the search and development of drugs with new mechanisms of action has stalled. Therefore, there is an urgent need to explore not just novel compounds, but novel approaches for the treatment of PTSD. A promising new approach involves the use of psychedelic drugs. Within the past few years, two psychedelics have received breakthrough designations for psychiatric indications from the US Food and Drug Administration, and several psychedelics are currently being investigated for the treatment of PTSD. This review discusses four types of compounds: 3,4-methylenedioxymethamphetamine (MDMA), ketamine, classical psychedelics (e.g. psilocybin and LSD) and cannabinoids. We describe the therapeutic rationale, the setting in which they are being administered, and their current state of evidence in the treatment of PTSD. Each compound provides unique qualities for the treatment of PTSD, from their use to rapidly target symptoms, to their use as adjuncts to facilitate psychotherapeutic treatments. Several questions are formulated that outline an agenda for future research.”

Long-term effects of psychedelic drugs: A systematic review

Authors: Jacob S. Aday, Cayla M. Mitzkovitz, Emily K. Bloescha, Christopher C. Davoli & Alan K. Davis

Published: 15 Mar 2020

One sentence summary: Summarizing the (long term) mostly positive, therapeutic, effects of psychedelics in research papers (34 articles selected).

“Research into the basic effects and therapeutic applications of psychedelic drugs has grown considerably in recent years. Yet, pressing questions remain regarding the substances’ lasting effects. Although individual studies have begun monitoring sustained changes, no study to-date has synthesized this information. Therefore, this systematic review aims to fill this important gap in the literature by synthesizing results from 34 contemporary experimental studies which included classic psychedelics, human subjects, and follow-up latencies of at least two weeks. The bulk of this work was published in the last five years, with psilocybin being the most frequently administered drug. Enduring changes in personality/attitudes, depression, spirituality, anxiety, wellbeing, substance misuse, meditative practices, and mindfulness were documented. Mystical experiences, connectedness, emotional breakthrough, and increased neural entropy were related to these long-term changes in psychological functioning. Finally, with proper screening, preparation, supervision, and integration, limited aversive side effects were noted by study participants. Future researchers should focus on including larger and more diverse samples, lengthier longitudinal designs, stronger control conditions, and standardized dosages.”

Acute Effects of 2C-E in Humans: An Observational Study

Authors: Esther Papaseit, Eulalia Olesti, Clara Pérez-Mañá, Marta Torrens, Marc Grifell, Mireia Ventura, Oscar J. Pozo, Elizabeth B. de Sousa Fernandes Perna, Johannes G. Ramaekers, Rafael de la Torre & Magí Farré

Published: 15 Mar 2020

One sentence summary: 2C-E peaks at 2 hours and produces effects similar to 2C-B.

“2,5-Dimethoxy-4-ethylphenethylamine (2C-E) is psychedelic phenylethylamine, with a chemical structure similar to mescaline, used as new psychoactive substance (NPS). It inhibits norepinephrine and serotonin uptake and, more relevant, acts as a partial agonist of the serotonin 2A (5-HT2A), 2B (5-HT2B), and (5-HT2C) receptors. Consumers have reported that 2C-E induces mild-moderate psychedelic effects, but its pharmacology in humans, including pharmacological effects and pharmacokinetics, have not yet studied. To assess the acute effects of 2C-E on physiological and subjective effects and evaluate its pharmacokinetics, an observational study was carried-out. Ten recreational users of psychedelics self-administered a single oral dose of 2C-E (6.5, 8, 10, 15, or 25 mg). Blood pressure and heart rate were evaluated at baseline, 2, 4, and 6 h post-administration. Three rating scales were administered to evaluate subjective effects: a set of Visual Analog Scales (VAS), the 49-item short form version of the Addiction Research Centre Inventory (ARCI), and the Evaluation of the Subjective Effects of Substances with Abuse Potential (VESSPA-SSE) at baseline, 2, 4, and 6 h after self-administration. To assess 2C-E concentrations oral fluid (saliva) was collected during 6 h. 2C-E induced primarily alterations in perceptions, hallucinations, and euphoric-mood. Saliva maximal concentrations were achieved 2 h after self-administration. Administration of oral 2C-E at recreational doses produces a group of psychedelic-like effects such to 2C-B and other serotonin-acting drugs.”

Metabolic engineering of Saccharomyces cerevisiae for the production of psilocybin and related tryptamine derivatives

Authors: N. Milne, P. Thomsen, N. Mølgaard Knudsen, P. Rubaszka, M. Kristensen & I. Borodina

Published: 27 Mar 2020

One sentence summary: Production of psilocybin in bakers yeast (Saccharomyces cerevisiae) achieved.

“Psilocybin is a tryptamine-derived psychoactive alkaloid found mainly in the fungal genus Psilocybe, among others, and is the active ingredient in so-called “magic mushrooms”. Although its notoriety originates from its psychotropic properties and popular use as a recreational drug, clinical trials have recently recognized psilocybin as a promising candidate for the treatment of various psychological and neurological afflictions. In this work, we demonstrate the de novo biosynthetic production of psilocybin and related tryptamine derivatives in Saccharomyces cerevisiae by expression of a heterologous biosynthesis pathway sourced from Psilocybe cubensis. Additionally, we achieve improved product titers by supplementing the pathway with a novel cytochrome P450 reductase from P. cubensis. Further rational engineering resulted in a final production strain producing 627 ± 140 mg/L of psilocybin and 580 ± 276 mg/L of the dephosphorylated degradation product psilocin in triplicate controlled fed-batch fermentations in minimal synthetic media. Pathway intermediates baeocystin, nor norbaeocystin as well the dephosphorylated baeocystin degradation product norpsilocin were also detected in strains engineered for psilocybin production. We also demonstrate the biosynthetic production of natural tryptamine derivative aeruginascin as well as the production of a new-to-nature tryptamine derivative N-acetyl-4-hydroxytryptamine. These results lay the foundation for the biotechnological production of psilocybin in a controlled environment for pharmaceutical applications, and provide a starting point for the biosynthetic production of other tryptamine derivatives of therapeutic relevance.”