Behavioural Brain Research
August 23, 2021
Carolina Aparecida Faria Almeida, Antônio Alves Pereira-Júnior, Jéssica Gonçalves Rangel et al.
33 citations
Repeated ethanol administration to mice produced behavioral sensitization, a model of alcohol use disorder. Subsequent daily treatment with ayahuasca (1.76 mg/kg DMT) for eight days attenuated that sensitization. Ayahuasca also reduced the anxiety-like behavior triggered by ethanol withdrawal and prevented ethanol-induced changes in 5-HT1a receptor and prodynorphin levels in the hippocampus, while reducing ethanol's effects on the dynorphin/prodynorphin ratio in the striatum. The results suggest ayahuasca may modulate neuroplastic changes caused by ethanol.
Frontiers in chemistry
January 1, 2020
Gabriela de Oliveira Silveira, Felipe Rebello Lourenço, Vítor Bruno et al.
12 citations
A greener, faster method using hollow fiber liquid-phase microextraction (HF-LPME) and LC-MS/MS was developed to measure DMT and three harmala alkaloids in human urine. The method avoids large amounts of toxic solvents. It detects DMT at 1.0 ng/ml and harmala alkaloids at 2.0 ng/ml, with a quantifiable range of 5-200 ng/ml. Precision, accuracy, and recovery (above 80%) met acceptance criteria. Analysis of urine from four subjects confirmed the method's feasibility. The approach offers a simple, time-saving alternative for studying ayahuasca components in biological samples.
Journal of Psychopharmacology
September 22, 2025
Vítor Bruno, Martha López-canul, Brandon Richardson et al.
3 citations
Psilocybin, at a dose of 10 mg/kg administered every other day, does not produce conditioned place preference (CPP) in Sprague-Dawley rats, indicating a lack of rewarding or reinforcing effects under this regimen. During conditioning, psilocybin increased head twitching, wet-dog shaking, and defecation, while decreasing grooming, body licking, and rearing compared to vehicle. However, 48 hours after the final injection, no behavioral differences remained between groups. These findings suggest that psilocybin's acute behavioral effects are transient and that it does not induce reward-related learning in the CPP paradigm, though further research is needed to assess addiction liability across different protocols.
Progress in Neuro-Psychopharmacology and Biological Psychiatry
October 1, 2025
Brandon Richardson, Antonio Inserra, Michael Pileggi et al.
2 citations
Psilocybin and lisuride both activate 5-HT2A receptors, but only psilocybin triggers the head twitch response (HTR) in mice, a proxy for hallucinogenic activity. In adult male C57BL/6N mice, psilocybin (0.3–3 mg/kg) inhibited serotonin neuron firing in the dorsal raphe nucleus via 5-HT2A receptors, while lisuride (0.1–0.5 mg/kg) did not. Both drugs reduced dopamine neuron firing in the substantia nigra, but lisuride's effect was more sensitive to 5-HT2A antagonism. Psilocybin elicited HTR; lisuride did not. Only high-dose lisuride reduced immobility in the forced swim test. Both drugs reduced locomotion in open field and elevated plus maze tests. Principal component analysis separated the drug effects, indicating distinct neurobiological pathways: psilocybin produces psychedelic-like, serotonin-dominant effects, while lisuride displays dopamine-linked improvements in coping behavior.
December 13, 2019
Vítor Bruno
1 citation
Ayahuasca, a psychoactive beverage containing DMT, is used by indigenous populations in religious rituals. Recent studies propose hallucinogens as treatments for central nervous system disorders like depression, anxiety, and addiction. This study tested whether ayahuasca could prevent the expression of cocaine-induced behavioral sensitization in C57Bl/6 mice. At lower doses (1.76 and 3.0 mg/kg DMT), ayahuasca did not prevent sensitization. Higher doses (15, 30, and 45 mg/kg DMT) did prevent it. However, analysis of serotonin receptors 5-HT1A and 5-HT2A in the prefrontal cortex, striatum, and hippocampus showed no significant differences between groups. These results suggest ayahuasca may be a promising therapeutic strategy for cocaine addiction, warranting further research.
Talanta
January 27, 2026
Fabiana Pereira Santos, Beatriz Aparecida Passos Bismara Paranhos, Thaisa Meira Sandini et al.
A greener analytical method using dispersive liquid-liquid microextraction and LC-MS/MS was developed to measure N,N-dimethyltryptamine (DMT) and three β-carbolines (harmine, harmaline, tetrahydroharmine) in human hair. The method was sensitive, with limits of quantification from 3 to 8 pg/mg, and linear up to 1000 pg/mg. Recovery was low (36-58%), but selectivity showed no interference. Applied to six real samples, DMT concentrations ranged from 21.5 to 204.4 pg/mg, while β-carbolines were generally higher, with harmine reaching over 1000 pg/mg. The method uses less organic solvent than conventional hair extraction, advancing green analytical toxicology for psychoactive alkaloids.
Archives of Toxicology
November 12, 2025
Gilles Salles, Carolina Aparecida de Faria Almeida, Isabella de Carvalho Alves et al.
Ayahuasca compounds N,N-dimethyltryptamine (DMT) and harmine (HRE), both alone and combined, partially protected human SH-SY5Y neuroblastoma cells from cocaine-induced toxicity. Cells exposed to cocaine with DMT and/or HRE showed increased viability compared to cocaine-only groups. Flow cytometry indicated partial to complete protection against apoptosis, and western blot revealed reduced expression of the apoptosis marker caspase-8 in co-treated cells. These findings suggest Ayahuasca-derived alkaloids merit further research for neuroprotection and treatment of substance use disorders.
Psychopharmacology
October 31, 2025
Vítor Bruno, Lídia Emmanuela Wiazowski Spelta, Matheus Lujan Pereira et al.
Ayahuasca, a brew containing DMT and β-carbolines used in indigenous rituals, has shown potential for treating substance use disorders. In C57Bl/6 mice, ayahuasca at a high dose (15 mg DMT/kg) induced rewarding effects, but these were weaker than those of cocaine. When mice were conditioned with cocaine and later treated with ayahuasca (12.5 or 15 mg DMT/kg), the brew prevented the reinstatement of cocaine-induced conditioned place preference after a cocaine challenge. The findings suggest ayahuasca may have therapeutic value for cocaine use disorder by reducing relapse to drug-seeking behavior.
Research Square
July 25, 2025
Vítor Bruno, Lídia Emmanuela Wiazowski Spelta, Matheus Lujan Pereira et al.
Ayahuasca, a psychedelic brew used in indigenous rituals, reduced the reinstatement of cocaine-induced conditioned place preference in C57Bl/6 mice, suggesting potential for treating cocaine use disorder. While ayahuasca itself produced rewarding effects at the highest dose tested (15 mg DMT/kg), these were weaker than those of cocaine (10 mg/kg). Treatment with ayahuasca (12.5 or 15 mg DMT/kg) after cocaine conditioning and before a cocaine challenge effectively prevented the reactivation of drug-associated contextual preference. The findings indicate therapeutic value for ayahuasca in cocaine use disorder, though research in humans remains limited.
Digital Library of Theses and Dissertations (Universidade de São Paulo)
May 12, 2025
Vítor Bruno
In male C57Bl/6 mice, ayahuasca at 15 mg DMT/kg produced a conditioned place preference, indicating reinforcing potential. Ayahuasca did not prevent the acquisition of cocaine-induced CPP, but acute administration of ayahuasca (12.5 or 15 mg DMT/kg) blocked the expression of cocaine CPP, and both doses prevented reinstatement of cocaine CPP. Gene expression analysis in the prefrontal cortex showed upregulation of Arc, Cebpd, Egr1, Egr2, Egr4, Fos, Junb, and Nr4a1, and downregulation of Reln. In male Sprague-Dawley rats, psilocybin (10 mg/kg) did not produce CPP under either alternate-day or consecutive-day conditioning. Consecutive-day psilocybin reduced neuronal activity in the ventral tegmental area after 48 hours of withdrawal, without observable behavioral changes.