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José Alexandre S. Crippa

23 papers in the library · 3,723 citations · publishing 0-2022

Papers

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Effects of ayahuasca on the endocannabinoid system of healthy volunteers and in volunteers with social anxiety disorder: Results from two pilot, proof‐of‐concept, randomized, placebo‐controlled trials

Human Psychopharmacology Clinical and Experimental February 2, 2022 Rafael G. Dos Santos, Juliana Mendes Rocha, Giordano Novak Rossi et al. 20 citations

Abstract Objective To assess endocannabinoid (anandamide, AEA; 2‐arachidonoylglycerol, 2‐AG) plasma levels in healthy volunteers and in volunteers with social anxiety disorder (SAD) after a single oral dose of ayahuasca or placebo. Methods Post hoc analysis of endocannabinoid plasma levels (baseline, 90 and 240 min after drug intake) from two parallel‐group, randomized, placebo‐controlled...

Harmine impairs memory performance of treated rats and nontreated cagemates.

Experimental and Clinical Psychopharmacology November 4, 2021 Tânia Cristina Libânio, R. Eufrásio, Suzy S Niigaki et al. 6 citations

The interest in psychedelic substances as potential treatments for psychiatric disorders is increasing. The β-carboline harmine, an Ayahuasca component, presents hallucinogenic and antidepressant effects. Although Ayuahuasca-and consequently harmine-is usually consumed in rituals, the role of social contexts in the behavioral effects of harmine has not been investigated yet. In this sense,...

Neuropharmacological Effects of the Main Phytocannabinoids: A Narrative Review.

Advances in experimental medicine and biology 2021 Rafael G. Dos Santos, Jaime E. C. Hallak, José Alexandre S. Crippa

Cannabis can synthetize more than 400 compounds, including terpenes, flavonoids, and more than 100 phytocannabinoids. The main phytocannabinoids are Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis-based products are used as medicines in several countries. In this text, we present an overview of the main neurochemical mechanisms of action of the phytocannabinoids, especially THC...

Serotonergic hallucinogens and recognition of facial emotion expressions: a systematic review of the literature

Therapeutic Advances in Psychopharmacology 2019 Juliana Mendes Rocha, Flávia de Lima Osório, José Alexandre S. Crippa et al. 44 citations

Background: Recognition of emotions in facial expressions (REFE) is a key aspect of social cognition. Anxiety and mood disorders are associated with deficits in REFE, and anxiolytics and antidepressants reverse these deficits. Recent studies have shown that serotonergic hallucinogens (i.e. ayahuasca, dimethyltryptamine, psilocybin, lysergic acid diethylamide [LSD], and mescaline) have...

Possible Interactions Between 5-HT2A Receptors and the Endocannabinoid System in Humans

Journal of Clinical Psychopharmacology October 19, 2018 Rafael G. Dos Santos, José Alexandre S. Crippa, Flávia de Lima Osório et al. 9 citations

dos Santos, Rafael Guimarães PhD; Crippa, José Alexandre MD, PhD; Osório, Flávia de Lima PhD; Rocha, Juliana M. BSc; Rossi, Giordano Novak BSc; Marchioni, Camila BSc; Queiroz, Maria Eugênia Costa PhD; Silveira, Gabriela O. BSc; Yonamine, Mauricio PhD; Hallak, Jaime Eduardo Cecilio MD, PhD Author Information

Well-being, problematic alcohol consumption and acute subjective drug effects in past-year ayahuasca users: a large, international, self-selecting online survey

Scientific Reports November 3, 2017 Will Lawn, Jaime E. C. Hallak, José Alexandre S. Crippa et al. 78 citations

Abstract Ayahuasca is a natural psychedelic brew, which contains dimethyltryptamine (DMT). Its potential as a psychiatric medicine has recently been demonstrated and its non-medical use around the world appears to be growing. We aimed to investigate well-being and problematic alcohol use in ayahuasca users, and ayahuasca’s subjective effects. An online, self-selecting, global survey examining...

Assessing the Psychedelic “After-Glow” in Ayahuasca Users: Post-Acute Neurometabolic and Functional Connectivity Changes Are Associated with Enhanced Mindfulness Capacities

The International Journal of Neuropsychopharmacology May 17, 2017 Frederic Sampedro, Mario de la Fuente Revenga, Marta Valle et al. 205 citations

Background: Ayahuasca is a plant tea containing the psychedelic 5-HT2A agonist N,N-dimethyltryptamine and harmala monoamine-oxidase inhibitors. Acute administration leads to neurophysiological modifications in brain regions of the default mode network, purportedly through a glutamatergic mechanism. Post-acutely, ayahuasca potentiates mindfulness capacities in volunteers and induces rapid and...

Anxiety, panic, and hopelessness during and after ritual ayahuasca intake in a woman with generalized anxiety disorder: A case report

Journal of Psychedelic Studies April 1, 2017 Rafael G. Dos Santos, Flávia de Lima Osório, José Alexandre S. Crippa et al. 7 citations

Ayahuasca is a dimethyltryptamine- and β-carboline-rich hallucinogenic beverage traditionally used by indigenous groups of Northwest Amazonian for ritual and therapeutic purposes. Animal and human studies suggest that ayahuasca has antidepressant and anxiolytic potentials and has a good safety profile. However, anxiety-like reactions may also occur after ayahuasca intake, although they are...

Effects of Ayahuasca and its Alkaloids on Drug Dependence: A Systematic Literature Review of Quantitative Studies in Animals and Humans

Journal of Psychoactive Drugs May 26, 2016 Amanda Amorin Nunes, Rafael G. Dos Santos, Flávia de Lima Osório et al. 92 citations

Recently, the anti-addictive potential of ayahuasca, a dimethyltryptamine(DMT)- and β-carboline-rich hallucinogenic beverage traditionally used by indigenous groups of the Northwest Amazon and currently by syncretic churches worldwide, has received increased attention. To better evaluate this topic, we performed a systematic literature review using the PubMed database to find quantitative...

Antidepressive, anxiolytic, and antiaddictive effects of ayahuasca, psilocybin and lysergic acid diethylamide (LSD): a systematic review of clinical trials published in the last 25 years

Therapeutic Advances in Psychopharmacology March 18, 2016 Rafael G. Dos Santos, Flávia de Lima Osório, José Alexandre S. Crippa et al. 306 citations

To date, pharmacological treatments for mood and anxiety disorders and for drug dependence show limited efficacy, leaving a large number of patients suffering severe and persistent symptoms. Preliminary studies in animals and humans suggest that ayahuasca, psilocybin and lysergic acid diethylamide (LSD) may have antidepressive, anxiolytic, and antiaddictive properties. Thus, we conducted a...

Antidepressive and anxiolytic effects of ayahuasca: a systematic literature review of animal and human studies

Brazilian Journal of Psychiatry March 1, 2016 Rafael G. Dos Santos, Flávia de Lima Osório, José Alexandre S. Crippa et al. 158 citations

Considering the need for new drugs that produce fewer adverse effects and are more effective in reducing anxiety and depression symptomatology, the described effects of ayahuasca and its alkaloids should be further investigated.

Antidepressant Effects of a Single Dose of Ayahuasca in Patients With Recurrent Depression

Journal of Clinical Psychopharmacology December 11, 2015 Rafael Faria Sanches, Flávia de Lima Osório, Rafael G. Dos Santos et al. 468 citations

Ayahuasca is an Amazonian botanical hallucinogenic brew which contains dimethyltryptamine, a 5-HT2A receptor agonist, and harmine, a monoamine-oxidase A inhibitor. Our group recently reported that ayahuasca administration was associated with fast-acting antidepressive effects in 6 depressive patients. The objective of the present work was to assess the antidepressive potentials of ayahuasca in...

The Psychedelic State Induced by Ayahuasca Modulates the Activity and Connectivity of the Default Mode Network

PLoS One February 18, 2015 Fernanda Palhano-Fontes, Kátia C. Andrade, Luís Fernando Tófoli et al. 461 citations

The experiences induced by psychedelics share a wide variety of subjective features, related to the complex changes in perception and cognition induced by this class of drugs. A remarkable increase in introspection is at the core of these altered states of consciousness. Self-oriented mental activity has been consistently linked to the Default Mode Network (DMN), a set of brain regions more...

Long-term use of psychedelic drugs is associated with differences in brain structure and personality in humans

European Neuropsychopharmacology January 16, 2015 José Carlos Bouso, Fernanda Palhano-Fontes, Antoni Rodrı́guez-fornells et al. 221 citations

Psychedelic agents have a long history of use by humans for their capacity to induce profound modifications in perception, emotion and cognitive processes. Despite increasing knowledge of the neural mechanisms involved in the acute effects of these drugs, the impact of sustained psychedelic use on the human brain remains largely unknown. Molecular pharmacology studies have shown that...

Effects of cannabinoid drugs on the deficit of prepulse inhibition of startle in an animal model of schizophrenia: the SHR strain

Frontiers in Pharmacology 2014 Raquel Levin, Fernanda Fiel Peres, Valéria de Almeida et al. 73 citations

Clinical and neurobiological findings suggest that the cannabinoids and the endocannabinoid system may be implicated in the pathophysiology and treatment of schizophrenia. We described that the spontaneously hypertensive rats (SHR) strain presents a schizophrenia behavioral phenotype that is specifically attenuated by antipsychotic drugs, and potentiated by proschizophrenia manipulations. Based...

Cannabis affects people differently: inter-subject variation in the psychotogenic effects of Δ9-tetrahydrocannabinol: a functional magnetic resonance imaging study with healthy volunteers

Psychological Medicine October 1, 2012 Zerrin Atakan, Sagnik Bhattacharyya, Paul Allen et al. 54 citations

BACKGROUND: Cannabis can induce transient psychotic symptoms, but not all users experience these adverse effects. We compared the neural response to Δ9-tetrahydrocannabinol (THC) in healthy volunteers in whom the drug did or did not induce acute psychotic symptoms. Method In a double-blind, placebo-controlled, pseudorandomized design, 21 healthy men with minimal experience of cannabis were...

Acute Effects of a Single, Oral dose of d9-tetrahydrocannabinol (THC) and Cannabidiol (CBD) Administration in Healthy Volunteers

Current Pharmaceutical Design September 12, 2012 Rocío Martín‐Santos, José Alexandre S. Crippa, Albert Batalla et al. 288 citations

RATIONALE: Animal and humans studies suggest that the two main constituents of cannabis sativa, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have quite different acute effects. However, to date the two compounds have largely been studied separately. OBJECTIVE: To evaluate and compare the acute pharmacological effects of both THC and CBD in the same human volunteers. METHODS: A...

Seeing with the eyes shut: Neural basis of enhanced imagery following ayahuasca ingestion

Human Brain Mapping September 16, 2011 Dráulio Barros de Araújo, Sidarta Ribeiro, Guillermo Cecchi et al. 241 citations

Abstract The hallucinogenic brew Ayahuasca, a rich source of serotonergic agonists and reuptake inhibitors, has been used for ages by Amazonian populations during religious ceremonies. Among all perceptual changes induced by Ayahuasca, the most remarkable are vivid “seeings.” During such seeings, users report potent imagery. Using functional magnetic resonance imaging during a closed‐eyes...

Performance of schizophrenic patients in the Stroop Color Word Test and electrodermal responsiveness after acute administration of cannabidiol (CBD)

Brazilian Journal of Psychiatry March 1, 2010 Jaime E. C. Hallak, João Paulo Machado‐de‐Sousa, José Alexandre S. Crippa et al. 122 citations

OBJECTIVE: The last decade has seen increasing evidence of dysfunctions in the endogenous cannabinoid system in schizophrenia and of its relationship with the typical cognitive impairment of the disorder. Studies in animal models, healthy volunteers, and psychotic patients clearly suggest an antipsychotic-like effect of cannabidiol. This study investigated the effects of cannabidiol on...

Modulation of effective connectivity during emotional processing by Δ9-tetrahydrocannabinol and cannabidiol

The International Journal of Neuropsychopharmacology September 24, 2009 Paolo Fusar‐poli, Paul Allen, Sagnik Bhattacharyya et al. 165 citations

Cannabis sativa, the most widely used illicit drug, has profound effects on levels of anxiety in animals and humans. Although recent studies have helped provide a better understanding of the neurofunctional correlates of these effects, indicating the involvement of the amygdala and cingulate cortex, their reciprocal influence is still mostly unknown. In this study dynamic causal modelling (DCM)...

Neuroimaging in cannabis use: a systematic review of the literature

Psychological Medicine July 23, 2009 Rocío Martín‐Santos, Ana B. Fagundo, José Alexandre S. Crippa et al. 207 citations

BACKGROUND: We conducted a systematic review to assess the evidence for specific effects of cannabis on brain structure and function. The review focuses on the cognitive changes associated with acute and chronic use of the drug. METHOD: We reviewed literature reporting neuroimaging studies of chronic or acute cannabis use published up until January 2009. The search was conducted using Medline,...

Interactive Effects of Ayahuasca and Cannabidiol in Social Cognition in Healthy Volunteers: A Pilot, Proof-of-Concept, Feasibility, Randomized-Controlled Trial.

Journal of Clinical Psychopharmacology Giordano Novak Rossi, Juliana Mendes Rocha, Flávia L. Osório et al. 12 citations

Serotonergic hallucinogens and cannabinoids may alter the recognition of emotions in facial expressions (REFE). Cannabidiol (CBD) attenuates the psychoactive effects of the cannabinoid-1 agonist tetrahydrocannabinol. Ayahuasca is a dimethyltryptamine-containing hallucinogenic decoction. It is unknown if CBD may moderate and attenuate the effects of ayahuasca on REFE. Seventeen healthy...