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1.
Transl Psychiatry ; 14(1): 191, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622150

RESUMO

Microdosing psychedelic drugs at a level below the threshold to induce hallucinations is an increasingly common lifestyle practice. However, the effects of microdosing on sleep have not been previously reported. Here, we report results from a Phase 1 randomized controlled trial in which 80 healthy adult male volunteers received a 6-week course of either LSD (10 µg) or placebo with doses self-administered every third day. Participants used a commercially available sleep/activity tracker for the duration of the trial. Data from 3231 nights of sleep showed that on the night after microdosing, participants in the LSD group slept an extra 24.3 min per night (95% Confidence Interval 10.3-38.3 min) compared to placebo-with no reductions of sleep observed on the dosing day itself. There were no changes in the proportion of time spent in various sleep stages or in participant physical activity. These results show a clear modification of the physiological sleep requirements in healthy male volunteers who microdose LSD. The clear, clinically significant changes in objective measurements of sleep observed are difficult to explain as a placebo effect. Trial registration: Australian New Zealand Clinical Trials Registry: A randomized, double-blind, placebo-controlled trial of repeated microdoses of lysergic acid diethylamide (LSD) in healthy volunteers; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=381476 ; ACTRN12621000436875.


Assuntos
Alucinógenos , Duração do Sono , Adulto , Humanos , Masculino , Austrália , Alucinógenos/farmacologia , Sono , Voluntários Saudáveis , Método Duplo-Cego
2.
Addict Biol ; 29(4): e13386, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600715

RESUMO

Alcohol use disorder (AUD) remains one of the most prevalent psychiatric disorders worldwide with high economic costs. Current treatment options show modest efficacy and relapse rates are high. Furthermore, there are increases in the treatment gap and few new medications have been approved in the past 20 years. Recently, psychedelic-assisted therapy with psilocybin and lysergic acid diethylamide has garnered significant attention in the treatment of AUD. Yet, they require significant amounts of therapist input due to prolonged subjective effects (~4-12 h) leading to high costs and impeding implementation. Accordingly, there is an increasing interest in the rapid and short-acting psychedelic 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT). This paper offers a first look at potential therapeutic mechanisms for AUD by reviewing the current literature on 5-MeO-DMT. Primarily, 5-MeO-DMT is able to induce mystical experiences and ego-dissolution together with increases in psychological flexibility and mindfulness. This could decrease AUD symptoms through the alleviation of psychiatric mood-related comorbidities consistent with the negative reinforcement and self-medication paradigms. In addition, preliminary evidence indicates that 5-MeO-DMT modulates neural oscillations that might subserve ego-dissolution (increases in gamma), psychological flexibility and mindfulness (increases in theta), and the reorganization of executive control networks (increases in coherence across frequencies) that could improve emotion regulation and inhibition. Finally, animal studies show that 5-MeO-DMT is characterized by neuroplasticity, anti-inflammation, 5-HT2A receptor agonism, and downregulation of metabotropic glutamate receptor 5 with clinical implications for AUD and psychiatric mood-related comorbidities. The paper concludes with several recommendations for future research to establish the purported therapeutic mechanisms of action.


Assuntos
Alcoolismo , Alucinógenos , Animais , Humanos , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , N,N-Dimetiltriptamina , Metoxidimetiltriptaminas/farmacologia , Metoxidimetiltriptaminas/uso terapêutico , Alcoolismo/tratamento farmacológico , Consumo de Bebidas Alcoólicas
3.
Molecules ; 29(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38542886

RESUMO

Cannabis sativa is one of the oldest plants utilized by humans for both economic and medical purposes. Although the use of cannabis started millennia ago in the Eastern hemisphere, its use has moved and flourished in the Western nations in more recent centuries. C. sativa is the source of psychoactive cannabinoids that are consumed as recreational drugs worldwide. The C21 aromatic hydrocarbons are restricted in their natural occurrence to cannabis (with a few exceptions). Delta-9-tetrahydrocannabinol (Δ9-THC) is the main psychoactive component in cannabis, with many pharmacological effects and various approved medical applications. However, a wide range of side effects are associated with the use of Δ9-THC, limiting its medical use. In 1966, another psychoactive cannabinoid, Delta-8-tetrahydrocannabinol (Δ8-THC) was isolated from marijuana grown in Maryland but in very low yield. Δ8-THC is gaining increased popularity due to its better stability and easier synthetic manufacturing procedures compared to Δ9-THC. The passing of the U.S. Farm Bill in 2018 led to an increase in the sale of Δ8-THC in the United States. The marketed products contain Δ8-THC from synthetic sources. In this review, methods of extraction, purification, and structure elucidation of Δ8-THC will be presented. The issue of whether Δ8-THC is a natural compound or an artifact will be discussed, and the different strategies for its chemical synthesis will be presented. Δ8-THC of synthetic origin is expected to contain some impurities due to residual amounts of starting materials and reagents, as well as side products of the reactions. The various methods of analysis and detection of impurities present in the marketed products will be discussed. The pharmacological effects of Δ8-THC, including its interaction with CB1 and CB2 cannabinoid receptors in comparison with Δ9-THC, will be reviewed.


Assuntos
Canabinoides , Cannabis , Dronabinol/análogos & derivados , Alucinógenos , Humanos , Dronabinol/farmacologia , Canabinoides/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Alucinógenos/farmacologia
4.
Am J Ther ; 31(2): e178-e182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38518273

RESUMO

The reviews in this special edition have presented a primer on the state of the literature for 7 different psychedelic compounds and their plausible roles in medicine. In a common format underscoring strengths, weakness, opportunities, and threats (SWOT), this article addresses how psychedelic compounds fit into the broader health care landscape for indicated conditions. Historically, psychiatric pathologies have been treated with small-molecule compounds that have limited effect sizes and carry a variety of adverse effect profiles. Psychedelic medicines offer the opportunity to provide more potent and rapidly acting treatments. It is crucial to note that this is an emerging field of medicine, and only one of these compounds (esketamine) is currently Food and Drug Administration-approved for depression. The other compounds discussed are investigational, and this discussion is both imaginative and prospective in nature.


Assuntos
Alucinógenos , Humanos , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , Estudos Prospectivos , Atenção Primária à Saúde
5.
Am J Ther ; 31(2): e97-e103, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38518266

RESUMO

BACKGROUND: Psychedelic drugs have recently emerged as plausibly effective pharmacological agents for the management of depression, anxiety, and other neuropsychiatric conditions, including those that are treatment-resistent. The latter half of the 20th century marked a revolution in the treatment of mental illnesses, exemplified by the introduction of selective serotonin reuptake inhibitors and other pharmacological agents. Nevertheless, mental illness remains a major public health crisis, affecting nearly one billion individuals worldwide. AREAS OF UNCERTAINTY: Because of the decades-long status of several psychedelics as Schedule I drugs, there have not been very many large, double-blind, randomized controlled trials of psychedelics. Owing to small sample sizes, there may be rare yet serious adverse events that have not been reported in the clinical trials thus far. THERAPEUTIC ADVANCES: Esketamine, a dissociative hallucinogen drug, was approved for the management of major depressive disorder by the Food and Drug Administration in 2019. As of January 2024, two Phase III trials of 3,4-methylenedioxymethamphetamine (MDMA), a synthetic drug that inhibits the serotonin transporter, have been completed; the results indicate that MDMA is superior to existing pharmacological treatments for post-traumatic stress disorder. A phase III trial of psilocybin, a naturally occurring serotonin receptor partial agonist, is currently underway. The following series details the current state of research in psychedelic therapeutics, including lysergic acid diethylamide (LSD), N-N-dimethyltryptamine (DMT) and ayahuasca, psilocybin, ibogaine, MDMA, and ketamine. LIMITATIONS: While initial clinical trials of psychedelics for depression were very promising, trials of psilocybin with larger sample sizes (100+ participants) suggest that its remission rate is 25%-29%. This is about the same as the remission rate of antidepressants, which is roughly 30% according to the landmark STAR*D trial. CONCLUSIONS: Psychedelic drugs and structural derivatives offer a great deal of promise for the management of a wide range of psychiatric morbidities. It is imperative that clinicians become familiar with these novel agents and learn how to integrate psychedelic therapy with the rest of their care through open communication and referral.


Assuntos
Transtorno Depressivo Maior , Alucinógenos , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/uso terapêutico , Atenção Primária à Saúde , Psilocibina/farmacologia , Psilocibina/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Am J Ther ; 31(2): e112-e120, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38518268

RESUMO

BACKGROUND: N,N-dimethyltryptamine (DMT) is a naturally occurring serotonergic psychedelic found in natural plants around the globe. As the main psychoactive component in ayahuasca, which also contains monoamine oxidase inhibitors, DMT has been consumed as plant-based brew by indigenous peoples for centuries. Further research is required to delineate the therapeutic utility of DMT. AREAS OF UNCERTAINTY: Although previous research has shown that DMT is synthesized endogenously, it may not be produced at physiologically relevant concentrations. Additionally, the phenomenological similarities between the DMT-induced state and near-death experiences led to the popular hypothesis that endogenous DMT is released during the dying process. However, this hypothesis continues to be debated. Generally, DMT and ayahuasca seem to be physiologically and psychiatrically safe, although ayahuasca is known to cause transient vomiting. THERAPEUTIC ADVANCES: A double-blind, randomized controlled trial showed that, within 1 week, ayahuasca causes remission in 36% of patients with treatment-resistant depression. According to top-line results from a recent phase IIa trial, 57% of patients with major depressive disorder experienced remission 12 weeks after receiving a single intravenous dose of DMT. LIMITATIONS: There has only been a single published double-blind randomized controlled trial on ayahuasca and 2 on DMT. All clinical trials have had small sample sizes (≤34 participants). DMT requires further research to understand its therapeutic and clinical potential as a psychedelic. CONCLUSIONS: Preliminary evidence indicates that ayahuasca and DMT may be more effective than existing antidepressants for treating major depressive disorder and treatment-resistant depression.


Assuntos
Banisteriopsis , Transtorno Depressivo Maior , Alucinógenos , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , N,N-Dimetiltriptamina/farmacologia , N,N-Dimetiltriptamina/uso terapêutico , Atenção Primária à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Artigo em Inglês | MEDLINE | ID: mdl-38307161

RESUMO

Psychedelics (serotonergic hallucinogens) are psychoactive substances that can alter perception and mood, and affect cognitive functions. These substances activate 5-HT2A receptors and may exert therapeutic effects. Some of the disorders for which psychedelic-assisted therapy have been studied include depression, addiction, anxiety and post-traumatic stress disorder. Despite the increasing number of studies reporting clinical effectiveness, with fewer negative symptoms and, additionally, minimal side effects, questions remain to be explored in the field of psychedelic medicine. Although progress has been achieved, there is still little understanding of the relationship among human brain and the modulation induced by these drugs. The present article aimed to describe, review and highlight the most promising findings in the literature regarding the (putative) therapeutic effects of psychedelics.


Assuntos
Comportamento Aditivo , Alucinógenos , Humanos , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , Encéfalo
9.
Sci Rep ; 14(1): 4389, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388550

RESUMO

The therapeutic use of lysergic acid diethylamide (LSD) has resurfaced in the last decade, prompting further scientific investigation into its effectiveness in many animal models. Zebrafish (Danio rerio) are a popular model organism in medical sciences and are used to examine the repeated administration of pharmacological compounds. Previous zebrafish research found acute LSD altered behaviour and cortisol levels at high (250 µg/L) but not low (5-100 µg/L) levels. In this study, we used a motion tracking system to record and analyze the movement patterns of zebrafish after acute and repeated 10-day LSD exposure (1.5 µg/L, 15 µg/L, 150 µg/L) and after seven days of withdrawal. The open-field and novel object approach tests were used to examine anxiety-like behaviour, boldness, and locomotion. In the acute experiments we observed a significant decrease in high mobility with 1.5 µg/L, 15 µg/L, and 150 µg/L of LSD compared to the control and a decrease in velocity with 1.5 and 15 µg/L. In repeated experiments, there were no significant differences in the levels of anxiety, boldness, or locomotion between all LSD groups and controls immediately after 10-day treatment or after withdrawal.


Assuntos
Alucinógenos , Dietilamida do Ácido Lisérgico , Animais , Dietilamida do Ácido Lisérgico/farmacologia , Peixe-Zebra , Modelos Animais , Locomoção , Ansiedade , Alucinógenos/farmacologia
10.
Ageing Res Rev ; 96: 102211, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307424

RESUMO

Psychedelics have traditionally been used for spiritual and recreational purposes, but recent developments in psychotherapy have highlighted their potential as therapeutic agents. These compounds, which act as potent 5-hydroxytryptamine (5HT) agonists, have been recognized for their ability to enhance neural plasticity through the activation of the serotoninergic and glutamatergic systems. However, the implications of these findings for the treatment of neurodegenerative disorders, particularly dementia, have not been fully explored. In recent years, studies have revealed the modulatory and beneficial effects of psychedelics in the context of dementia, specifically Alzheimer's disease (AD)-related dementia, which lacks a definitive cure. Psychedelics such as N,N-dimethyltryptamine (DMT), lysergic acid diethylamide (LSD), and Psilocybin have shown potential in mitigating the effects of this debilitating disease. These compounds not only target neurotransmitter imbalances but also act at the molecular level to modulate signalling pathways in AD, including the brain-derived neurotrophic factor signalling pathway and the subsequent activation of mammalian target of rapamycin and other autophagy regulators. Therefore, the controlled and dose-dependent administration of psychedelics represents a novel therapeutic intervention worth exploring and considering for the development of drugs for the treatment of AD-related dementia. In this article, we critically examined the literature that sheds light on the therapeutic possibilities and pathways of psychedelics for AD-related dementia. While this emerging field of research holds great promise, further studies are necessary to elucidate the long-term safety, efficacy, and optimal treatment protocols. Ultimately, the integration of psychedelics into the current treatment paradigm may provide a transformative approach for addressing the unmet needs of individuals living with AD-related dementia and their caregivers.


Assuntos
Doença de Alzheimer , Alucinógenos , Humanos , Alucinógenos/farmacologia , Alucinógenos/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Dietilamida do Ácido Lisérgico/farmacologia , Dietilamida do Ácido Lisérgico/uso terapêutico , Psilocibina/farmacologia , Psilocibina/uso terapêutico , N,N-Dimetiltriptamina
11.
Behav Brain Res ; 465: 114924, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38423256

RESUMO

Given the critical role of maternal care in the neurodevelopment of offspring, this study aimed to investigate the effects of the psychedelic substance 25 H-NBOMe on maternal behavior in lactating rats and its subsequent impact on the social and neurodevelopmental behavior of the offspring. We administered two different dosages of 25 H-NBOMe (0.3 mg/kg and 1.0 mg/kg; i,p,) to lactating rats and observed changes in maternal behaviors, such as nest-building and pup retrieval, and in offspring behaviors, including social play. Behavioral assessments were complemented by physiological measurements to rule out general health or nutritional decline. 25 H-NBOMe significantly disrupted maternal behaviors, including nest-building and pup retrieval, without affecting the weight of dams or offspring. Offspring of exposed dams exhibited reduced social play behavior. Higher doses led to more pronounced disruptions, while lower doses, despite not visibly affecting maternal behavior, still impacted offspring behavior, suggesting potential direct effects of 25 H-NBOMe. The study highlights the potential risks associated with the use of 25 H-NBOMe during lactation, emphasizing its detrimental impact on maternal care and offspring development. These findings contribute to understanding the neurobiological effects of psychedelic substances during critical developmental periods and underscore the importance of avoiding their use.


Assuntos
Alucinógenos , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Ratos , Animais , Lactação/fisiologia , Alucinógenos/farmacologia , Comportamento Animal/fisiologia , Comportamento Materno/fisiologia
12.
J Psychopharmacol ; 38(3): 247-257, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38332655

RESUMO

BACKGROUND: Despite increasing medical cannabis use, research has yet to establish whether and to what extent products containing delta-9-tetrahydrocannabinol (THC) impact driving performance among patients. Stable doses of prescribed cannabinoid products during long-term treatment may alleviate clinical symptoms affecting cognitive and psychomotor performance. AIM: To examine the effects of open-label prescribed medical cannabis use on simulated driving performance among patients. METHODS: In a semi-naturalistic laboratory study, 40 adults (55% male) aged between 23 and 80 years, consumed their own prescribed medical cannabis product. Driving performance outcomes including standard deviation of lateral position (SDLP), the standard deviation of speed (SDS), mean speed and steering variability were evaluated using the Forum8 driving simulator at baseline (pre-dosing), 2.5 h and 5 -h (post-dosing). Perceived driving effort (PDE) was self-reported after each drive. Oral fluid and whole blood samples were collected at multiple timepoints and analysed for THC via liquid chromatography-mass spectrometry. RESULTS: A significant main effect of time was observed for mean speed (p = 0.014) and PDE (p = 0.020), with patients displaying modest stabilisation of vehicle control, increased adherence to speed limits and reductions in PDE post-dosing, relative to baseline. SDLP (p = 0.015) and PDE (p = 0.043) were elevated for those who consumed oil relative to flower-based products. Detectable THC concentrations were observed in oral fluid at 6-h post-dosing (range = 0-24 ng/mL). CONCLUSIONS: This semi-naturalistic study suggests that the consumption of medical cannabis containing THC (1.13-39.18 mg/dose) has a negligible impact on driving performance when used as prescribed.


Assuntos
Condução de Veículo , Cannabis , Alucinógenos , Fumar Maconha , Maconha Medicinal , Adulto , Humanos , Masculino , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Maconha Medicinal/farmacologia , Dronabinol/farmacologia , Alucinógenos/farmacologia , Desempenho Psicomotor , Cannabis/efeitos adversos , Fumar Maconha/efeitos adversos
13.
Sci Rep ; 14(1): 4343, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383569

RESUMO

Antibiotic resistance in staphylococcal strains and its impact on public health and agriculture are global problems. The development of new anti-staphylococcal agents is an effective strategy for addressing the increasing incidence of bacterial resistance. In this study, ethanolic extracts of Cannabis sativa L. made from plant parts harvested during the whole vegetation cycle under various nutritional treatments were assessed for in vitro anti-staphylococcal effects. The results showed that all the cannabis extracts tested exhibited a certain degree of growth inhibition against bacterial strains of Staphylococcus aureus, including antibiotic-resistant and antibiotic-sensitive forms. The highest antibacterial activity of the extracts was observed from the 5th to the 13th week of plant growth across all the nutritional treatments tested, with minimum inhibitory concentrations ranging from 32 to 64 µg/mL. Using HPLC, Δ9-tetrahydrocannabinolic acid (THCA) was identified as the most abundant cannabinoid in the ethanolic extracts. A homolog of THCA, tetrahydrocannabivarinic acid (THCVA), reduced bacterial growth by 74%. These findings suggest that the cannabis extracts tested in this study can be used for the development of new anti-staphylococcal compounds with improved efficacy.


Assuntos
Canabinoides , Cannabis , Alucinógenos , Canabinoides/farmacologia , Extratos Vegetais/farmacologia , Staphylococcus , Dronabinol/farmacologia , Antibacterianos/farmacologia , Alucinógenos/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Etanol/farmacologia
14.
Sci Rep ; 14(1): 4072, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374177

RESUMO

Psychedelic substances induce profound alterations in consciousness. Careful preparation is therefore essential to limit adverse reactions, enhance therapeutic benefits, and maintain user safety. This paper describes the development of a self-directed, digital intervention for psychedelic preparation. Drawing on elements from the UK Medical Research Council (MRC) framework for developing complex interventions, the design was informed by a four-factor model of psychedelic preparedness, using a person-centred approach. Our mixed-methods investigation consisted of two studies. The first involved interviews with 19 participants who had previously attended a 'high-dose' psilocybin retreat, systematically exploring their preparation behaviours and perspectives on the proposed intervention. The second study engaged 28 attendees of an ongoing psilocybin retreat in co-design workshops, refining the intervention protocol using insights from the initial interviews. The outcome is a co-produced 21-day digital course (Digital Intervention for Psychedelic Preparation (DIPP)), that is organised into four modules: Knowledge-Expectation, Psychophysical-Readiness, Safety-Planning, and Intention-Preparation. Fundamental components of the course include daily meditation practice, supplementary exercises tied to the weekly modules, and mood tracking. DIPP provides a comprehensive and scalable solution to enhance psychedelic preparedness, aligning with the broader shift towards digital mental health interventions.


Assuntos
Alucinógenos , Pentamidina/análogos & derivados , Humanos , Alucinógenos/farmacologia , Psilocibina/farmacologia , Saúde Mental , Estado de Consciência
15.
BMC Neurosci ; 25(1): 7, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317077

RESUMO

BACKGROUND: Microdosing psychedelics is a phenomenon with claimed cognitive benefits that are relatively untested clinically. Pre-clinically, psychedelics have demonstrated enhancing effects on neuroplasticity, which cannot be measured directly in humans, but may be indexed by non-invasive electroencephalography (EEG) paradigms. This study used a visual long-term potentiation (LTP) EEG paradigm to test the effects of microdosed lysergic acid diethylamide (LSD) on neural plasticity, both acutely while on the drug and cumulatively after microdosing every third day for six weeks. Healthy adult males (n = 80) completed the visual LTP paradigm at baseline, 2.5 h following a dose of 10 µg of LSD or inactive placebo, and 6 weeks later after taking 14 repeated microdoses. Visually induced LTP was used as indirect index of neural plasticity. Surface level event-related potential (ERPs) based analyses are presented alongside dynamic causal modelling of the source localised data using a generative thalamocortical model (TCM) of visual cortex to elucidate underlying synaptic circuitry. RESULTS: Event-related potential (ERP) analyses of N1b and P2 components did not show evidence of changes in visually induced LTP by LSD either acutely or after 6 weeks of regular dosing. However modelling the complete timecourse of the ERP with the TCM demonstrated changes in laminar connectivity in primary visual cortex. This primarily included changes to self-gain and inhibitory input parameters acutely. Layer 2/3 to layer 5 excitatory connectivity was also different between LSD and placebo groups. After regular dosing only excitatory input from layer 2/3 into layer 5 and inhibitory input into layer 4 were different between groups. CONCLUSIONS: Without modulation of the ERPs it is difficult to relate the findings to other studies visually inducing LTP. It also indicates the classic peak analysis may not be sensitive enough to demonstrate evidence for changes in LTP plasticity in humans at such low doses. The TCM provides a more sensitive approach to assessing changes to plasticity as differences in plasticity mediated laminar connectivity were found between the LSD and placebo groups. TRIAL REGISTRATION:  ANZCTR registration number ACTRN12621000436875; Registered 16/04/2021 https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=381476 .


Assuntos
Alucinógenos , Adulto , Humanos , Masculino , Alucinógenos/farmacologia , Dietilamida do Ácido Lisérgico/farmacologia , Potenciação de Longa Duração , Plasticidade Neuronal , Eletroencefalografia
16.
Sci Rep ; 14(1): 3097, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326357

RESUMO

Psilocybin, a serotonergic psychedelic, is being increasingly researched in clinical studies for the treatment of psychiatric disorders. The relatively lengthy duration of oral psilocybin's acute effects (4-6 h) may have pragmatic and cost-effectiveness limitations. Here, we explored the effects of intravenous (IV) N,N-Dimethyltryptamine (DMT), a closely related, but faster-acting psychedelic intervention, on mental health outcomes in healthy volunteers. Data is reported from two separate analyses: (1) A comparison of mental health-related variables 1 week after 7, 14, 18, and 20 mg of IV DMT versus IV saline placebo (n = 13) and, (2) A prospective dataset assessing effects before versus 2 weeks after 20 mg of IV DMT (n = 17). Mental health outcomes included measures of depression severity (QIDS-SR16), trait anxiety (STAI-T), Neuroticism (NEO-FFI), wellbeing (WHO-5), meaning in life (MLQ), optimism (LOT-R), and gratitude (GQ-6). In both the prospective and placebo-controlled datasets, significant improvements in scores of depression were found 1-2 weeks after DMT administration. Significant reductions in trait Neuroticism were only found for the placebo-controlled sample. Finally, changes in depression and trait anxiety correlated with acute peak experiences (assessed via 'Oceanic Boundlessness'). While the use of two separate cohorts in pooled analysis limits the generalizability of these correlational findings, these results suggest that DMT may reduce depressive symptomatology by inducing peak experiences. The short half-life of IV DMT and its potential for flexible dosing via controlled infusions makes it an appealing candidate for psychedelic medicine. Further research in clinical samples is needed to corroborate the therapeutic potential of DMT.


Assuntos
Alucinógenos , N,N-Dimetiltriptamina , Humanos , Alucinógenos/farmacologia , Psilocibina , Voluntários Saudáveis , Estudos Prospectivos , Avaliação de Resultados em Cuidados de Saúde
17.
ACS Chem Neurosci ; 15(3): 462-471, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38214686

RESUMO

Recent findings have shown that psychedelics reliably enhance brain entropy (understood as neural signal diversity), and this effect has been associated with both acute and long-term psychological outcomes, such as personality changes. These findings are particularly intriguing, given that a decrease of brain entropy is a robust indicator of loss of consciousness (e.g., from wakefulness to sleep). However, little is known about how context impacts the entropy-enhancing effect of psychedelics, which carries important implications for how it can be exploited in, for example, psychedelic psychotherapy. This article investigates how brain entropy is modulated by stimulus manipulation during a psychedelic experience by studying participants under the effects of lysergic acid diethylamide (LSD) or placebo, either with gross state changes (eyes closed vs open) or different stimuli (no stimulus vs music vs video). Results show that while brain entropy increases with LSD under all of the experimental conditions, it exhibits the largest changes when subjects have their eyes closed. Furthermore, brain entropy changes are consistently associated with subjective ratings of the psychedelic experience, but this relationship is disrupted when participants are viewing a video─potentially due to a "competition" between external stimuli and endogenous LSD-induced imagery. Taken together, our findings provide strong quantitative evidence of the role of context in modulating neural dynamics during a psychedelic experience, underlining the importance of performing psychedelic psychotherapy in a suitable environment.


Assuntos
Alucinógenos , Humanos , Alucinógenos/farmacologia , Dietilamida do Ácido Lisérgico , Encéfalo , Mapeamento Encefálico , Psicoterapia
18.
Neurosci Biobehav Rev ; 157: 105538, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38220035

RESUMO

Psychedelic agents, such as LSD and psilocybin, induce marked alterations in consciousness via activation of the 5-HT2A receptor (5-HT2ARs). We hypothesize that psychedelics enforce a state of synthetic surprise through the biased activation of the 5-HTRs system. This idea is informed by recent insights into the role of 5-HT in signaling surprise. The effects on consciousness, explained by the cognitive penetrability of perception, can be described within the predictive coding framework where surprise corresponds to prediction error, the mismatch between predictions and actual sensory input. Crucially, the precision afforded to the prediction error determines its effect on priors, enabling a dynamic interaction between top-down expectations and incoming sensory data. By integrating recent findings on predictive coding circuitry and 5-HT2ARs transcriptomic data, we propose a biological implementation with emphasis on the role of inhibitory interneurons. Implications arise for the clinical use of psychedelics, which may rely primarily on their inherent capacity to induce surprise in order to disrupt maladaptive patterns.


Assuntos
Alucinógenos , Humanos , Alucinógenos/farmacologia , Serotonina/farmacologia , Estado de Consciência , Transdução de Sinais
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