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1.
Int J Neuropsychopharmacol ; 20(9): 698-711, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28525587

RESUMEN

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 sustained antidepressant effects in treatment-resistant patients. However, the mechanisms underlying these fast and maintained effects are poorly understood. Here, we investigated in an open-label uncontrolled study in 16 healthy volunteers ayahuasca-induced post-acute neurometabolic and connectivity modifications and their association with mindfulness measures. Methods: Using 1H-magnetic resonance spectroscopy and functional connectivity, we compared baseline and post-acute neurometabolites and seed-to-voxel connectivity in the posterior and anterior cingulate cortex after a single ayahuasca dose. Results: Magnetic resonance spectroscopy showed post-acute reductions in glutamate+glutamine, creatine, and N-acetylaspartate+N-acetylaspartylglutamate in the posterior cingulate cortex. Connectivity was increased between the posterior cingulate cortex and the anterior cingulate cortex, and between the anterior cingulate cortex and limbic structures in the right medial temporal lobe. Glutamate+glutamine reductions correlated with increases in the "nonjudging" subscale of the Five Facets Mindfulness Questionnaire. Increased anterior cingulate cortex-medial temporal lobe connectivity correlated with increased scores on the self-compassion questionnaire. Post-acute neural changes predicted sustained elevations in nonjudging 2 months later. Conclusions: These results support the involvement of glutamate neurotransmission in the effects of psychedelics in humans. They further suggest that neurometabolic changes in the posterior cingulate cortex, a key region within the default mode network, and increased connectivity between the anterior cingulate cortex and medial temporal lobe structures involved in emotion and memory potentially underlie the post-acute psychological effects of ayahuasca.


Asunto(s)
Banisteriopsis/química , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Alucinógenos/farmacología , Atención Plena , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Mapeo Encefálico , Femenino , Estudios de Seguimiento , Ácido Glutámico/metabolismo , Voluntarios Sanos , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Factores de Tiempo
2.
Psychopharmacology (Berl) ; 233(5): 823-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26612618

RESUMEN

BACKGROUND: Ayahuasca is a psychotropic plant tea used for ritual purposes by the indigenous populations of the Amazon. In the last two decades, its use has expanded worldwide. The tea contains the psychedelic 5-HT2A receptor agonist N,N-dimethyltryptamine (DMT), plus ß-carboline alkaloids with monoamine-oxidase-inhibiting properties. Acute administration induces an introspective dream-like experience characterized by visions and autobiographic and emotional memories. Studies of long-term users have suggested its therapeutic potential, reporting that its use has helped individuals abandon the consumption of addictive drugs. Furthermore, recent open-label studies in patients with treatment-resistant depression found that a single ayahuasca dose induced a rapid antidepressant effect that was maintained weeks after administration. Here, we conducted an exploratory study of the psychological mechanisms that could underlie the beneficial effects of ayahuasca. METHODS: We assessed a group of 25 individuals before and 24 h after an ayahuasca session using two instruments designed to measure mindfulness capacities: The Five Facets Mindfulness Questionnaire (FFMQ) and the Experiences Questionnaire (EQ). RESULTS: Ayahuasca intake led to significant increases in two facets of the FFMQ indicating a reduction in judgmental processing of experiences and in inner reactivity. It also led to a significant increase in decentering ability as measured by the EQ. These changes are classic goals of conventional mindfulness training, and the scores obtained are in the range of those observed after extensive mindfulness practice. CONCLUSIONS: The present findings support the claim that ayahuasca has therapeutic potential and suggest that this potential is due to an increase in mindfulness capacities.


Asunto(s)
Banisteriopsis , Atención Plena , Extractos Vegetales/farmacología , Adulto , Carbolinas/farmacología , Femenino , Humanos , Juicio/efectos de los fármacos , Masculino , Persona de Mediana Edad , Inhibidores de la Monoaminooxidasa/farmacología , Receptor de Serotonina 5-HT2A/efectos de los fármacos , Agonistas de Receptores de Serotonina/farmacología , Encuestas y Cuestionarios
4.
PLoS One ; 10(9): e0137202, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26421727

RESUMEN

Ritual use of ayahuasca, an amazonian Amerindian medicine turned sacrament in syncretic religions in Brazil, is rapidly growing around the world. Because of this internationalization, a comprehensive understanding of the pharmacological mechanisms of action of the brew and the neural correlates of the modified states of consciousness it induces is important. Employing a combination of electroencephalogram (EEG) recordings and quantification of ayahuasca's compounds and their metabolites in the systemic circulation we found ayahuasca to induce a biphasic effect in the brain. This effect was composed of reduced power in the alpha band (8-13 Hz) after 50 minutes from ingestion of the brew and increased slow- and fast-gamma power (30-50 and 50-100 Hz, respectively) between 75 and 125 minutes. Alpha power reductions were mostly located at left parieto-occipital cortex, slow-gamma power increase was observed at left centro-parieto-occipital, left fronto-temporal and right frontal cortices while fast-gamma increases were significant at left centro-parieto-occipital, left fronto-temporal, right frontal and right parieto-occipital cortices. These effects were significantly associated with circulating levels of ayahuasca's chemical compounds, mostly N,N-dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine and some of their metabolites. An interpretation based on a cognitive and emotional framework relevant to the ritual use of ayahuasca, as well as it's potential therapeutic effects is offered.


Asunto(s)
Banisteriopsis/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Adulto , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Ondas Encefálicas/efectos de los fármacos , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Adulto Joven
7.
Biomed Chromatogr ; 26(3): 301-13, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21710581

RESUMEN

There is an increasing interest in potential medical applications of ayahuasca, a South American psychotropic plant tea with a long cultural history of indigenous medical and religious use. Clinical research into ayahuasca will require specific, sensitive and comprehensive methods for the characterization and quantitation of these compounds and their metabolites in blood. A combination of two analytical techniques (high-performance liquid chromatography with ultraviolet and/or fluorescence detection and gas chromatography with nitrogen-phosphorus detection) has been used for the analysis of some of the constituents of ayahuasca in blood following its oral consumption. We report here a single methodology for the direct analysis of 14 of the major alkaloid components of ayahuasca, including several known and potential metabolites of N,N-dimethyltryptamine and the harmala alkaloids in blood. The method uses 96-well plate/protein precipitation/filtration for plasma samples, and analysis by HPLC-ion trap-ion trap-mass spectrometry using heated electrospray ionization to reduce matrix effects. The method expands the list of compounds capable of being monitored in blood following ayahuasca administration while providing a simplified approach to their analysis. The method has adequate sensitivity, specificity and reproducibility to make it useful for clinical research with ayahuasca.


Asunto(s)
Banisteriopsis/química , Extractos Vegetales/sangre , Cromatografía Líquida de Alta Presión/métodos , Humanos , Masculino , Estándares de Referencia , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos
8.
J Clin Psychopharmacol ; 31(6): 717-26, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22005052

RESUMEN

Ayahuasca is an Amazonian psychotropic plant tea combining the 5-HT2A agonist N,N-dimethyltryptamine (DMT) and monoamine oxidase-inhibiting ß-carboline alkaloids that render DMT orally active. The tea, obtained from Banisteriopsis caapi and Psychotria viridis, has traditionally been used for religious, ritual, and medicinal purposes by the indigenous peoples of the region. More recently, the syncretistic religious use of ayahuasca has expanded to the United States and Europe. Here we conducted a double-blind randomized crossover clinical trial to investigate the physiological impact of ayahuasca in terms of autonomic, neuroendocrine, and immunomodulatory effects. An oral dose of encapsulated freeze-dried ayahuasca (1.0 mg DMT/kg body weight) was compared versus a placebo and versus a positive control (20 mg d-amphetamine) in a group of 10 healthy volunteers. Ayahuasca led to measurable DMT plasma levels and distinct subjective and neurophysiological effects that were absent after amphetamine. Both drugs increased pupillary diameter, with ayahuasca showing milder effects. Prolactin levels were significantly increased by ayahuasca but not by amphetamine, and cortisol was increased by both, with ayahuasca leading to the higher peak values. Ayahuasca and amphetamine induced similar time-dependent modifications in lymphocyte subpopulations. Percent CD4 and CD3 were decreased, whereas natural killer cells were increased. Maximum changes occurred around 2 hours, returning to baseline levels at 24 hours. In conclusion, ayahuasca displayed moderate sympathomimetic effects, significant neuroendocrine stimulation, and a time-dependent modulatory effect on cell-mediated immunity. Future studies on the health impact of long-term ayahuasca consumption should consider the assessment of immunological status in regular users.


Asunto(s)
Banisteriopsis/química , Dextroanfetamina/farmacología , N,N-Dimetiltriptamina/farmacología , Extractos Vegetales/farmacología , Administración Oral , Adulto , Estudios Cruzados , Método Doble Ciego , Alucinógenos/aislamiento & purificación , Alucinógenos/farmacocinética , Alucinógenos/farmacología , Humanos , Inmunidad Celular , Masculino , N,N-Dimetiltriptamina/aislamiento & purificación , N,N-Dimetiltriptamina/farmacocinética , Prolactina/sangre , Factores de Tiempo , Adulto Joven
9.
Biomed Chromatogr ; 25(9): 970-84, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21058415

RESUMEN

Ayahuasca, also known as caapi or yage among various South American groups, holds a highly esteemed and millennia-old position in these cultures' medical and religious pharmacopeia. There is now an increasing interest in the potential for modern medical applications of ayahuasca, as well as concerns regarding its increasing potential for abuse. Toxicological and clinical research to address these issues will require information regarding its metabolism and clearance. Thus, a rapid, sensitive and specific method for characterization and quantitation of the major constituents and of the metabolites of ayahuasca in urine is needed. The present research provides a protocol for conducting such analyses. The characteristics of the method, conducted by sample dilution and using HPLC-electrospray ionization (ESI)-selected reaction monitoring (SRM)-tandem mass spectrometry, are presented. The application of the analytical protocol to urine samples collected from three individuals that were administered ayahuasca has also been demonstrated. The data show that the major metabolite of the hallucinogenic component of ayahuasca, N,N-dimethyltryptamine (DMT), is the corresponding N-oxide, the first time this metabolite has been described in in vivo studies in humans. Further, very little DMT was detected in urine, despite the inhibition of monoamine oxidase afforded by the presence of the harmala alkaloids in ayahuasca. The major harmala alkaloid excreted was tetrahydroharmine. Other excretion products and metabolites were also identified and quantified. The method described would be suitable for use in further toxicological and clinical research on ayahuasca.


Asunto(s)
Banisteriopsis/química , Cromatografía Líquida de Alta Presión/métodos , N,N-Dimetiltriptamina/orina , Extractos Vegetales/orina , Plantas Medicinales/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Humanos , N,N-Dimetiltriptamina/metabolismo , Extractos Vegetales/metabolismo , América del Sur
10.
J Chromatogr A ; 1216(51): 8960-8, 2009 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-19926090

RESUMEN

A direct injection/liquid chromatography-electrospray ionization-tandem mass spectrometry procedure has been developed for the simultaneous quantitation of 11 compounds potentially found in the increasingly popular Amazonian botanical medicine and religious sacrament ayahuasca. The method utilizes a deuterated internal standard for quantitation and affords rapid detection of the alkaloids by a simple dilution assay, requiring no extraction procedures. Further, the method demonstrates a high degree of specificity for the compounds in question, as well as low limits of detection and quantitation despite using samples for analysis that had been diluted up to 200:1. This approach also appears to eliminate potential matrix effects. Method bias for each compound, examined over a range of concentrations, was also determined as was inter- and intra-assay variation. Its application to the analysis of three different ayahuasca preparations is also described. This method should prove useful in the study of ayahuasca in clinical and ethnobotanical research as well as in forensic examinations of ayahuasca preparations.


Asunto(s)
Alcaloides/análisis , Banisteriopsis/química , Cromatografía Liquida/métodos , Plantas Medicinales/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Triptaminas/análisis , Alcaloides/química , Brasil , Peso Molecular , Psicotrópicos/análisis , Psicotrópicos/química , Estándares de Referencia , Reproducibilidad de los Resultados , Factores de Tiempo , Triptaminas/química
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