OPEN Foundation

D. de Araujo

Changes in inflammatory biomarkers are related to the antidepressant effects of Ayahuasca

Abstract

Background: Ayahuasca is a traditional Amazon brew and its potential antidepressant properties have recently been explored in scientific settings. We conducted a double-blind placebo-controlled trial of ayahuasca with treatment-resistant depression patients (n = 28) and healthy controls (n = 45).

Aims: We are evaluating the blood inflammatory biomarkers: C-reactive protein and interleukin 6, as a potential consequence of ayahuasca intake and their correlation with serum cortisol and brain-derived neurotrophic factor levels. Blood samples were collected at pre-treatment and 48 hours after substance ingestion to assess the concentration of inflammatory biomarkers, together with administration of the Montgomery-Åsberg Depression Rating Scale.

Results: At pre-treatment, patients showed higher C-reactive protein levels than healthy controls and a significant negative correlation between C-reactive protein and serum cortisol levels was revealed (rho = -0.40, n = 14). C-reactive protein in those patients was not correlated with Montgomery-Åsberg Depression Rating Scale scores. We observed a significant reduction of C-reactive protein levels across time in both patients and controls treated with ayahuasca, but not with placebo. Patients treated with ayahuasca showed a significant correlation (rho = + 0.57) between larger reductions of C-reactive protein and lower depressive symptoms at 48 hours after substance ingestion (Montgomery-Åsberg Depression Rating Scale). No significant result with respect to interleukin 6 and brain-derived neurotrophic factor was found. Furthermore, these biomarkers did not predict the antidepressant response or remission rates observed.

Conclusions: These findings enhance the understanding of the biological mechanisms behind the observed antidepressant effects of ayahuasca and encourage further clinical trials in adults with depression.

Galvão-Coelho, N. L., de Menezes Galvão, A. C., de Almeida, R. N., Palhano-Fontes, F., Campos Braga, I., Lobão Soares, B., … & de Araujo, D. B. (2020). Changes in inflammatory biomarkers are related to the antidepressant effects of Ayahuasca. Journal of Psychopharmacology34(10), 1125-1133; 10.1177/0269881120936486
Link to full text

Subacute Effects of the Psychedelic Ayahuasca on the Salience and Default Mode Networks

Abstract

Background: Neuroimaging studies have just begun to explore the acute effects of psychedelics on large-scale brain networks’ functional organization. Even less is known about the neural correlates of subacute effects taking place days after the psychedelic experience. This study explores the subacute changes of primary sensory brain networks and networks supporting higher-order affective and self-referential functions 24 hours after a single session with the psychedelic ayahuasca.
Methods: We leveraged task-free functional magnetic resonance imaging data 1 day before and 1 day after a randomized placebo-controlled trial exploring the effects of ayahuasca in naïve healthy participants (21 placebo/22 ayahuasca). We derived intra- and inter-network functional connectivity of the salience, default mode, visual, and sensorimotor networks, and assessed post-session connectivity changes between the ayahuasca and placebo groups. Connectivity changes were associated with Hallucinogen Rating Scale scores assessed during the acute effects.
Results: Our findings revealed increased anterior cingulate cortex connectivity within the salience network, decreased posterior cingulate cortex connectivity within the default mode network, and increased connectivity between the salience and default mode networks 1 day after the session in the ayahuasca group compared to placebo. Connectivity of primary sensory networks did not differ between groups. Salience network connectivity increases correlated with altered somesthesia scores, decreased default mode network connectivity correlated with altered volition scores, and increased salience default mode network connectivity correlated with altered affect scores.
Conclusion: These findings provide preliminary evidence for subacute functional changes induced by the psychedelic ayahuasca on higher-order cognitive brain networks that support interoceptive, affective, and self-referential functions.

Pasquini, L., Palhano-Fontes, F., & de Araujo, D. B. (2019). Subacute effects of the psychedelic ayahuasca on the salience and default mode networks. medRxiv, 19007542., https://doi.org/10.1177/0269881120909409
Link to full text

The Impact of Ayahuasca on Suicidality: Results From a Randomized Controlled Trial.

Abstract

Suicide is a major public health problem. Given increasing suicide rates and limitations surrounding current interventions, there is an urgent need for innovative interventions for suicidality. Although ayahuasca has been shown to target mental health concerns associated with suicidality (i.e., depression and hopelessness), research has not yet explored the impact of ayahuasca on suicidality. Therefore, we conducted secondary analyses of a randomized placebo-controlled trial in which individuals with treatment-resistant depression were administered one dose of ayahuasca (n = 14) or placebo (n = 15). Suicidality was assessed by a trained psychiatrist at baseline, as well as 1 day, 2 days, and 7 days after the intervention. A fixed-effects linear mixed model, as well as between and within-groups Cohen’s d effect sizes were used to examine changes in suicidality. Controlling for baseline suicidality, we found a significant effect for time (p < .05). The effect of the intervention (i.e., ayahuasca vs. placebo) trended toward significance (p = .088). At all time points, we found medium between-group effect sizes (i.e., ayahuasca vs. placebo; day 1 Cohen’s d = 0.58; day 2 d = 0.56; day 7 d = 0.67), as well as large within-group (ayahuasca; day 1 Cohen’s d = 1.33; day 2 d = 1.42; day 7 d = 1.19) effect sizes, for decreases in suicidality. Conclusions: This research is the first to explore the impact of ayahuasca on suicidality. The findings suggest that ayahuasca may show potential as an intervention for suicidality. We highlight important limitations of the study, potential mechanisms, and future directions for research on ayahuasca as an intervention for suicidality. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02914769.

Zeifman, R., Palhano-Fontes, F., Hallak, J., Nunes, E. A., Maia-de-Oliveira, J. P., & de Araujo, D. B. (2019). The Impact of Ayahuasca on Suicidality: Results From a Randomized Controlled Trial. Frontiers in Pharmacology10, 1325.
Link to full text

Shannon entropy of brain functional complex networks under the influence of the psychedelic Ayahuasca

Abstract

The entropic brain hypothesis holds that the key facts concerning psychedelics are partially explained in terms of increased entropy of the brain’s functional connectivity. Ayahuasca is a psychedelic beverage of Amazonian indigenous origin with legal status in Brazil in religious and scientific settings. In this context, we use tools and concepts from the theory of complex networks to analyze resting state fMRI data of the brains of human subjects under two distinct conditions: (i) under ordinary waking state and (ii) in an altered state of consciousness induced by ingestion of Ayahuasca. We report an increase in the Shannon entropy of the degree distribution of the networks subsequent to Ayahuasca ingestion. We also find increased local and decreased global network integration. Our results are broadly consistent with the entropic brain hypothesis. Finally, we discuss our findings in the context of descriptions of “mind-expansion” frequently seen in self-reports of users of psychedelic drugs.
Viol, A., Palhano-Fontes, F., Onias, H., de Araujo, D. B., & Viswanathan, G. M. (2016). Shannon entropy of brain functional complex networks under the influence of the psychedelic Ayahuasca. arXiv preprint arXiv:1611.00358. 10.1038/s41598-017-06854-0
Link to full text

Short term changes in the proteome of human cerebral organoids induced by 5-methoxy-N,N-dimethyltryptamine

Abstract

Dimethyltryptamines are hallucinogenic serotonin-like molecules present in traditional Amerindian medicine (e.g. Ayahuasca, Virola) recently associated with cognitive gains, antidepressant effects and changes in brain areas related to attention, self-referential thought, and internal mentation. Historical and technical restrictions impaired understanding how such substances impact human brain metabolism. Here we used shotgun mass spectrometry to explore proteomic differences induced by dimethyltryptamine (5-methoxy-N,N-dimethyltryptamine, 5-MeO-DMT) on human cerebral organoids. Out of the 6,728 identified proteins, 934 were found differentially expressed in 5-MeO-DMT-treated cerebral organoids. In silico systems biology analyses support 5-MeO-DMT’s anti-inflammatory effects and reveal a modulation of proteins associated with the formation of dendritic spines, including proteins involved in cellular protrusion formation, microtubule dynamics and cytoskeletal reorganization. Proteins involved in long-term potentiation were modulated in a complex manner, with significant increases in the levels of NMDAR, CaMKII and CREB, but a reduction of PKA and PKC levels. These results offer possible mechanistic insights into the neuropsychological changes caused by the ingestion of substances rich in dimethyltryptamines.

Dakic, V., Nascimento, J. M., Sartore, R. C., de Moraes Maciel, R., de Araujo, D. B., Ribeiro, S., … & Rehen, S. K. (2017). Short term changes in the proteome of human cerebral organoids induced by 5-methoxy-N, N-dimethyltryptamine. bioRxiv, 108159.
Link to full text

Treating Addiction: Perspectives from EEG and Imaging Studies on Psychedelics

Abstract

Despite reports of apparent benefits, social and political pressure beginning in the late 1960s effectively banned scientific inquiry into psychedelic substances. Covert examination of psychedelics persisted through the 1990s; the turn of the century and especially the past 10 years, however, has seen a resurgent interest in psychedelic substances (eg, LSD, ayahuasca, psilocybin). This chapter outlines relevant EEG and brain imaging studies evaluating the effects of psychedelics on the brain. This chapter also reviews evidence of the use of psychedelics as adjunct therapy for a number of psychiatric and addictive disorders. In particular, psychedelics appear to have efficacy in treating depression and alcohol-use disorders.

Tófoli, L. F., & de Araujo, D. B. (2016). Treating Addiction: Perspectives from EEG and Imaging Studies on Psychedelics. International Review of Neurobiology. 10.1016/bs.irn.2016.06.005
Link to full text

30 April - Q&A with Rick Strassman

X