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

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 imagery task, we found that Ayahuasca produces a robust increase in the activation of several occipital, temporal, and frontal areas. In the primary visual area, the effect was comparable in magnitude to the activation levels of natural image with the eyes open. Importantly, this effect was specifically correlated with the occurrence of individual perceptual changes measured by psychiatric scales. The activity of cortical areas BA30 and BA37, known to be involved with episodic memory and the processing of contextual associations, was also potentiated by Ayahuasca intake during imagery. Finally, we detected a positive modulation by Ayahuasca of BA 10, a frontal area involved with intentional prospective imagination, working memory and the processing of information from internal sources. Therefore, our results indicate that Ayahuasca seeings stem from the activation of an extensive network generally involved with vision, memory, and intention. By boosting the intensity of recalled images to the same level of natural image, Ayahuasca lends a status of reality to inner experiences. It is therefore understandable why Ayahuasca was culturally selected over many centuries by rain forest shamans to facilitate mystical revelations of visual nature. Hum Brain Mapp, 2012. (c) 2011 Wiley Periodicals, Inc.

Gas Chromatographic Analysis of Dimethyltryptamine and beta-Carboline Alkaloids in Ayahuasca, an Amazonian Psychoactive Plant Beverage

Introduction - Ayahuasca is obtained by infusing the pounded stems of Banisteriopsis caapi in combination with the leaves of Psychotria viridis. P. viridis is rich in the psychedelic indole N,N-dimethyltryptamine, whereas B. caapi contains substantial amounts of beta-carboline alkaloids, mainly harmine, harmaline and tetrahydroharmine, which are monoamine-oxidase inhibitors. Because of differences in composition in ayahuasca preparations, a method to measure their main active constituents is needed. Objective - To develop a gas chromatographic method for the simultaneous determination of dimethyltryptamine and the main beta-carbolines found in ayahuasca preparations. Methodology - The alkaloids were extracted by means of solid phase extraction (C(18)) and detected by gas chromatography with nitrogen/phosphorous detector. Results - The lower limit of quantification (LLOQ) was 0.02 mg/mL for all analytes. The calibration curves were linear over a concentration range of 0.02-4.0 mg/mL (r(2) > 0.99). The method was also precise (RSD < 10%). Conclusion - A simple gas chromatographic method to determine the main alkaloids found in ayahuasca was developed and validated. The method can be useful to estimate administered doses in animals and humans for further pharmacological and toxicological investigations of ayahuasca. Copyright (C) 2009 John Wiley & Sons, Ltd.

qNMR: An applicable method for the determination of dimethyltryptamine in ayahuasca, a psychoactive plant preparation

Ayahuasca is an Amazonian plant beverage obtained by infusing the pounded stems of Banisteriopsis caapi in combination with the leaves of Psychotria viridis. P. viridis contains the psychedelic indole N,N-dimethyltryptamine (DMT). This association has a wide range of use in religious rituals around the world. In the present work, an easy, fast and non-destructive method by Nuclear Magnetic Resonance of proton ((1)H NMR) for quantification of DMT in ayahuasca samples was developed and validated. 2,5-Dimethoxybenzaldehyde (DMBO) was used as internal standard (IS). For this purpose, the area ratios produced by protons of DMT (N(CH(3))(2)) at 2.70 ppm, singlet, (6H) and for DMBO (Ar(OCH(3))(2)) at 3.80 and 3.89 ppm, doublet, (6H) were used for quantification. The lower limit of quantification (LLOQ) was 12.5 mu g/mL and a good intra-assay precision was also obtained (relative standard deviation < 5.1%). The present (1)H NMR method is not time consuming and can be readily applied to monitor this tryptamine in plant preparations. We believe that qNMR can be used for identification and quantification of many plant-based products and metabolites with important advantages, while comparing with other analytical techniques. (C) 2010 Phytochemical Society of Europe. Published by Elsevier B. V. All rights reserved.

Determination of dimethyltryptamine and beta-carbolines (ayahuasca alkaloids) in plasma samples by LC-MS/MS

Background: Ayahuasca is a psychoactive plant beverage originally used by indigenous people throughout the Amazon Basin, long before its modern use by syncretic religious groups established in Brazil, the USA and European countries. The objective of this study was to develop a method for quantification of dimethyltryptamine and beta-carbolines in human plasma samples. Results: The analytes were extracted by means of C18 cartridges and injected into LC-MS/MS, operated in positive ion mode and multiple reaction monitoring. The LOQs obtained for all analytes were below 0.5 ng/ml. By using the weighted least squares linear regression, the accuracy of the analytical method was improved at the lower end of the calibration curve (from 0.5 to 100 ng/ml; r(2)> 0.98). Conclusion: The method proved to be simple, rapid and useful to estimate administered doses for further pharmacological and toxicological investigations of ayahuasca exposure.

Neurobehavioral, reflexological and physical development of Wistar rat offspring exposed to ayahuasca during pregnancy and lactation

Ayahuasca is a hallucinogenic beverage prepared by the decoction of plants native to the Amazon Basin region. The beverage has been used throughout the world by members of some syncretic religious movements. Despite the recent legalization of ayahuasca in Brazil for religious purposes, there is little pre-clinical and clinical information attesting to its safety, particularly in relation to the use during pregnancy. The aim of the current work was to determine the effects of perinatal exposure to ayahuasca (from the 6th day of pregnancy to the 10th day of lactation) on physical, reflexology and neurobehavioral parameters of the Wistar rat offspring. The offspring showed no statistically significant changes in the physical and reflexology parameters evaluated. However, in adult rats, perinatally exposed to ayahuasca, an increase in frequency of entries in open arms in elevated plus-maze test, a decrease in total time of interaction in social interaction test, a decrease in time of latency for the animal to start swimming and a decrease of the minimum convulsant dose induced by pentylenetetrazol were observed. In conclusion, our results showed that the use of ayahuasca by mothers during pregnancy and lactation reduced the general anxiety and social motivation of the rat offspring. Besides, it promoted a higher sensitivity for initiation and spread of seizure activity.

Maternal and Developmental Toxicity of Ayahuasca in Wistar Rats

INTRODUCTION: Ayahuasca is a psychotropic plant beverage initially used by shamans throughout the Amazon region during traditional religious cult. In recent years, ayahuasca has also been used in ceremonies of a number of modern syncretic religious groups, including pregnant women. However, no documented study has been performed to evaluate the risk of developmental toxicity of ayahuasca. METHODS: In the present work, maternal and developmental toxicity was evaluated in Wistar rats. Ayahuasca was administered to pregnant rats in three different doses [the equivalent typical dose (TD) administered to humans, five-fold TD and 10-fold TD] during the gestational period (6-20 days). RESULTS: Dams treated with the highest ayahuasca dose showed maternal toxicity with decrease of weight gain and food intake. Visceral fetal findings were observed in all treatment groups. Skeletal findings were observed in the intermediate- and high-dose groups. The fetuses deriving from the highest dose group also presented a decrease in body weight. CONCLUSIONS: From these results, it is possible to conclude that there is a risk of maternal and developmental toxicity following ayahuasca exposure and that the level of toxicity appears to be dose-dependent. Birth Defects Res (Part B) 89:207-212, 2010. (C) 2010 Wiley-Liss, Inc.

The natural hallucinogen 5-MeO-DMT, component of Ayahuasca, disrupts cortical function in rats: reversal by antipsychotic drugs

5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) is a natural hallucinogen component of Ayahuasca, an Amazonian beverage traditionally used for ritual, religious and healing purposes that is being increasingly used for recreational purposes in US and Europe. 5MeO-DMT is of potential interest for schizophrenia research owing to its hallucinogenic properties. Two other psychotomimetic agents, phencyclidine and 2,5-dimethoxy-4-iodo-phenylisopropylamine (DOI), markedly disrupt neuronal activity and reduce the power of low frequency cortical oscillations (<4 Hz, LFCO) in rodent medial prefrontal cortex (mPFC). Here we examined the effect of 5-MeO-DMT on cortical function and its potential reversal by antipsychotic drugs. Moreover, regional brain activity was assessed by blood-oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI). 5-MeO-DMT disrupted mPFC activity, increasing and decreasing the discharge of 51 and 35% of the recorded pyramidal neurons, and reducing (−31%) the power of LFCO. The latter effect depended on 5-HT1A and 5-HT2A receptor activation and was reversed by haloperidol, clozapine, risperidone, and the mGlu2/3 agonist LY379268. Likewise, 5-MeO-DMT decreased BOLD responses in visual cortex (V1) and mPFC. The disruption of cortical activity induced by 5-MeO-DMT resembles that produced by phencyclidine and DOI. This, together with the reversal by antipsychotic drugs, suggests that the observed cortical alterations are related to the psychotomimetic action of 5-MeO-DMT. Overall, the present model may help to understand the neurobiological basis of hallucinations and to identify new targets in antipsychotic drug development.

Ethnographie de l'usage rituel d'ayahuasca au Québec

L’ayahuasca est une décoction de plantes originaires de la forêt amazonienne. Elle contient la vigne nommée ayahuasca (Banistereopsis caapi) et un arbuste (Psychotria viridis). Ces plantes contiennent des substances psychoactives. Respectivement il s’agit de l’harmine et de la diméthyle-tryptamine (DMT). Ce mélange est utilisé par plusieurs peuples autochtones du bassin amazonien depuis une époque qui précède la Conquête. L’ayahuasca est utilisée par ces peuples à des fins chamaniques. Au début du 20e siècle, la demande en caoutchouc a engendrée une migration de travailleurs dans ces régions. Un de ces travailleurs d’origine africaine est entré en contact avec cette substance. De croyance chrétienne, il a interprété son expérience comme une rencontre avec le divin. Ceci l’a amené à fonder dans les années 30 une église syncrétique nommée Santo Daime. Depuis, l’utilisation rituelle d’ayahuasca est répandue dans le monde. Aujourd’hui, On retrouve au Québec des groupes faisant un usage rituel d’ayahuasca. Ce mémoire est une ethnographie d’un groupe actif au Québec. Ce groupe a fait l’objet d’observations participantes durant l’été 2010. L’étude a démontré que la participation aux cérémonies d’ayahuasca engendre des prises de conscience et le travail de groupe en permet l’intégration dans le quotidien des participants. De plus, la structure rituelle garanti un usage non abusif.

Alterações da default mode network provocadas pela ingestão de Ayahuasca investigadas por Ressonância Magnética Funcional

Ayahuasca is psychotropic beverage that has been used for ages by indigenous populations in South America, notably in the Amazon region, for religious and medicinal purposes. The tea is obtained by the decoction of leaves from the Psychotria viridis with the bark and stalk of a shrub, the Banisteriopsis caapi. The first is rich in N-N-dimethyltryptamine (DMT), which has an important and well-known hallucinogenic effect due to its agonistic action in serotonin receptors, specifically 5-HT2A. On the other hand, β-carbolines present in B. caapi, particularly harmine and harmaline, are potent monoamine oxidase inhibitors (MAOi). In addition, the tetrahydroharmine (THH), also present in B. caapi, acts as mild selective serotonin reuptake inhibitor and a weak MAOi. This unique composition induces a number of affective, sensitive, perceptual and cognitive changes in individuals under the effect of Ayahuasca. On the other hand, there is growing interest in the Default Mode Network (DMN), which has been consistently observed in functional neuroimaging studies. The key components of this network include structures in the brain midline, as the anterior medial frontal cortex, ventral medial frontal cortex, posterior cingulate cortex, precuneus, and some regions within the inferior parietal lobe and middle temporal gyrus. It has been argued that DMN participate in tasks involving self-judgments, autobiographical memory retrieval, mental simulations, thinking in perspective, meditative states, and others. In general, these tasks require an internal focus of attention, hence the conclusion that the DMN is associated with introspective mental activity. Therefore, this study aimed to evaluate by functional magnetic resonance imaging (fMRI) changes in DMN caused via the ingestion of Ayahuasca by 10 healthy subjects while submitted to two fMRI protocols: a verbal fluency task and a resting state acquisition. In general, it was observed that Ayahuasca causes a reduction in the fMRI signal in central nodes of DMN, such as the anterior cingulate cortex, the medial prefrontal cortex, the posterior cingulate cortex, precuneus and inferior parietal lobe. Furthermore, changes in connectivity patterns of the DMN were observed, especially a decrease in the functional connectivity of the precuneus. Together, these findings indicate an association between the altered state of consciousness experienced by individuals under the effect of Ayahuasca, and changes in the stream of spontaneous thoughts leading to an increased introspective mental activity

DISCURSOS SOBRE O USO RELIGIOSO DO PSICOATIVO AYAHUASCA

O tema Discursos sobre o uso religioso do psicoativo Ayahuasca , foi pesquisado de acordo com o método da análise do discurso, tendo como metodologia a coleta de dados na pesquisa bibliográfica e documental. O objetivo da presente dissertação é apresentar os diferentes discursos que são expressões das linguagens diversas que tem sido praticadas nos setores sociais que tratam do tema Ayahuasca. Todas as questões da vida tem em seu entorno discursos dos mais variados tipos, perfis e vertentes; discursos são como cursos de rios que correm e muitas vezes se interligam. Quando observamos os diferentes discursos e diálogos, que envolvem a ayahuasca, podemos perceber a imensa variação de ideias e grupos sociais envolvidos na discussão dos problemas pertinentes ao tema. Ao analisar o discurso taxonômico, percebemos a complexidade dos elementos que compõem os dois vegetais que são utilizados na confecção do chá. Observamos na linguagem histórico-antropológica um imenso caldeirão de culturas e conceitos, que se entrelaçam formando um mosaico de relações que se conectam. Atentando para o interdiscurso acadêmico científico listamos os diferentes grupos que estão estudando a ayahuasca e seus temas. No discurso e linguagem midiática encontramos as manchetes, que marcam os anos de existência dos diferentes grupos e seus respectivos conflitos, que contêm a linguagem policial, e que versam sobre os temas que envolvem a ayahuasca historicamente e contemporaneamente. Nos deparamos também com o discurso jurídico e regulador do Estado, que possui a documentação e os dispositivos de legalização sobre o uso da ayahuasca. Finalmente a linguagem e discurso das ciências da religião, que procura obter respostas sociais ao nascimento de religiosidade nas culturas, temas esses que estão cheios de símbolos, rituais e imaginários, que só podem ser explorados e entendidos dentro de seus próprios contextos quando utilizando das ferramentas da antropologia, da sociologia e da psicologia da religião.

Avaliação toxicológica da ayahuasca em ratos Wistar : comportamento e toxicidade reprodutiva em machos

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-Graduação em Ciências da Saúde, 2016.

The Psychedelic State Induced By Ayahuasca Modulates The Activity And Connectivity Of The Default Mode Network.

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 active during rest than during the execution of a goal-directed task. Here we used fMRI technique to inspect the DMN during the psychedelic state induced by Ayahuasca in ten experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians composed by a mixture of compounds that increase monoaminergic transmission. In particular, we examined whether Ayahuasca changes the activity and connectivity of the DMN and the connection between the DMN and the task-positive network (TPN). Ayahuasca caused a significant decrease in activity through most parts of the DMN, including its most consistent hubs: the Posterior Cingulate Cortex (PCC)/Precuneus and the medial Prefrontal Cortex (mPFC). Functional connectivity within the PCC/Precuneus decreased after Ayahuasca intake. No significant change was observed in the DMN-TPN orthogonality. Altogether, our results support the notion that the altered state of consciousness induced by Ayahuasca, like those induced by psilocybin (another serotonergic psychedelic), meditation and sleep, is linked to the modulation of the activity and the connectivity of the DMN.

Cola beverage consumption delays alveolar bone healing: a histometric study in rats

Epidemiological studies have suggested that cola beverage consumption may affect bone metabolism and increase bone fracture risk. Experimental evidence linking cola beverage consumption to deleterious effects on bone is lacking. Herein, we investigated whether cola beverage consumption from weaning to early puberty delays the rate of reparative bone formation inside the socket of an extracted tooth in rats. Twenty male Wistar rats received cola beverage (cola group) or tap water (control group) ad libitum from the age of 23 days until tooth extraction at 42 days and euthanasia 2 and 3 weeks later. The neoformed bone volume inside the alveolar socket was estimated in semi-serial longitudinal sections using a quantitative differential point-counting method. Histological examination suggested a decrease in the osteogenic process within the tooth sockets of rats from both cola groups, which had thinner and sparser new bone trabeculae. Histometric data confirmed that alveolar bone healing was significantly delayed in cola-fed rats at three weeks after tooth extraction (ANOVA, p = 0.0006, followed by Tukey's test, p < 0.01). Although the results of studies in rats cannot be extrapolated directly to human clinical dentistry, the present study provides evidence that cola beverage consumption negatively affect maxillary bone formation.

Sensory evaluation of black instant coffee beverage with some volatile compounds present in aromatic oil from roasted coffee

The oil obtained from Brazilian roasted coffee by supercritical CO2 extraction shows considerable aromatic properties, mainly composed by five aromatic compounds, 2-methylpyrazine; 2-furfurylalcohol, 2,5-dimethylpyrazine; γ-butyrolactone and 2-furfurylacetate. Sensory analyses were used to verify the influence of a mixture of these important classes of aromatic coffee compounds (pyrazines, furans and lactones) and of the roasted coffee aromatic oil on the coffee aroma and flavour of black instant freeze and spray-dried coffee beverages. In the acceptance evaluation of the aroma, the samples prepared with freeze-dried instant coffee without the mixture of volatile compounds (sample 4) were not significantly different from the freeze-dried instant coffee in which the aromatic coffee oil was added (sample 5) and from the sample prepared with freeze-dried coffee in which the mixture of the five volatile was added (sample 3), coincidentally from the same drying process. Therefore, sample (3) did not differ from samples prepared with spray dried instant coffee without (sample 1) and to which (sample 2) the mixture of volatile was added. Therefore, with respect to this attribute, the addition of this mixture did not interfere in this drink acceptance. Taking into consideration the flavor, samples prepared with freeze-dried instant coffee in which the aromatic coffee oil was added (5) and the samples with (3) and without (4) the mixture of the five volatile was added did not differ significantly, however sample (4) did not differ from samples (1) and (2). Regarding this attribute, the addition of the aromatic oil of roasted coffee or a mixture of volatile in samples of freeze-dried instant coffee had a better acceptance than those dried by spray dryer (1) and (2). Thus, the enrichment of drinks with the aromatic oil of roasted coffee, or even with the mixture of the five components did not influence the consumer acceptance with respect to the aroma, but exerts influence with respect to flavour.

Type of Alcoholic Beverage and Risk of Head and Neck Cancer-025EFA Pooled Analysis Within the INHANCE Consortium

The authors pooled data from 15 case-control studies of head and neck cancer (9,107 cases, 14,219 controls) to investigate the independent associations with consumption of beer, wine, and liquor. In particular, they calculated associations with different measures of beverage consumption separately for subjects who drank beer only (858 cases, 986 controls), for liquor-only drinkers (499 cases, 527 controls), and for wine-only drinkers (1,021 cases, 2,460 controls), with alcohol never drinkers (1,124 cases, 3,487 controls) used as a common reference group. The authors observed similar associations with ethanol-standardized consumption frequency for beer-only drinkers (odds ratios (ORs) = 1.6, 1.9, 2.2, and 5.4 for <= 5, 6-15, 16-30, and > 30 drinks per week, respectively; P(trend) < 0.0001) and liquor-only drinkers (ORs = 1.6, 1.5, 2.3, and 3.6; P < 0.0001). Among wine-only drinkers, the odds ratios for moderate levels of consumption frequency approached the null, whereas those for higher consumption levels were comparable to those of drinkers of other beverage types (ORs = 1.1, 1.2, 1.9, and 6.3; P < 0.0001). Study findings suggest that the relative risks of head and neck cancer for beer and liquor are comparable. The authors observed weaker associations with moderate wine consumption, although they cannot rule out confounding from diet and other lifestyle factors as an explanation for this finding. Given the presence of heterogeneity in study-specific results, their findings should be interpreted with caution.