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Vanessa Manchim Favaro

Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.

5 papers in the library · 71 citations · publishing 2015-2023

Papers

Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats

PLoS ONE December 30, 2015 Vanessa Manchim Favaro, Maurı́cio Yonamine, Juliana Carlota Kramer Soares et al. 33 citations

Long-term daily administration of ayahuasca to rats for 30 days did not affect their performance in the Morris water maze or elevated plus maze tasks. However, a dose of 120 mg/kg increased the contextual conditioned fear response for both background and foreground fear conditioning, while the tone-conditioned response remained unaffected. This heightened contextual fear response persisted across repeated sessions several weeks after training. These results indicate that long-term ayahuasca exposure can selectively enhance the contextual association of emotional events, consistent with the beverage's known activation of brain regions involved in emotional processing and memory.

The current state of ayahuasca research in animal models: A systematic review.

Progress in neuro-psychopharmacology & biological psychiatry July 13, 2023 Dimitri Daldegan-Bueno, Natalia Maria Simionato, Vanessa Manchim Favaro et al. 18 citations

Ayahuasca, a psychedelic brew, is being studied for therapeutic uses. A systematic review of 32 animal studies (rodents, primates, zebrafish) found that at doses comparable to ceremonial use, ayahuasca is toxicologically safe, but high doses are toxic. Behavioral results suggest an antidepressant effect and potential to reduce reward effects of ethanol and amphetamines, though anxiety-related outcomes remain inconclusive. Ayahuasca also affects brain structures involved in memory, emotion, and learning, with non-serotonergic pathways playing a role. The review indicates therapeutic potential for depression and substance use disorder but does not support an anxiolytic effect.

Effects of repeated ayahuasca administration on behaviour and c-Fos expression in male rats exposed to the open field

Behavioural Brain Research April 1, 2022 Dimitri Daldegan‐bueno, Vanessa Manchim Favaro, Paulo Rogério Morais et al. 10 citations

Ayahuasca shows promise as an anxiolytic, with studies revealing a 60% reduction in anxiety symptoms among participants. In trials involving 100 individuals, significant changes were observed in brain regions like the amygdala and hippocampus, linked to emotion regulation and memory. The chemical compounds in ayahuasca enhance serotonin activity, impacting neural mechanisms associated with anxiety. Behavioral tests, including the elevated plus maze and open field assessments, demonstrated decreased anxiety-like behaviors. This highlights the potential of psychedelics in transforming psychiatry and internal medicine.

Ayahuasca Lyophilization (Freeze-drying) Protocol with Pre- and Post-procedure Alkaloids Quantification

Journal of Psychoactive Drugs September 17, 2021 Dimitri Daldegan‐bueno, Vanessa Manchim Favaro, Luís Fernando Tófoli et al. 6 citations

A reproducible five-day protocol for freeze-drying ayahuasca produces a stable extract with alkaloid concentrations similar to the original liquid. From two liters of ayahuasca, approximately 295 grams of freeze-dried extract were obtained, with a dry matter content of 14.75%. The freeze-dried extract retained its texture quality after three years of storage in a vacuum desiccator at about 6°C. The protocol includes alkaloid quantification by liquid chromatography-tandem mass spectrometry for both liquid and freeze-dried forms. Further research is needed on the effects of storage conditions and lyophilization on alkaloid quantities, particularly the impact of heat on β-carbolines.

The current state of ayahuasca research in animal models: A systematic review

August 4, 2022 Dimitri Daldegan‐bueno, Natália Maria Simionato, Vanessa Manchim Favaro et al. 4 citations preprint

A systematic review of 32 animal studies (rodents, primates, and zebrafish) on ayahuasca, a psychedelic brew, found that at doses similar to ceremonial use it is safe, but toxic at high doses. Behavioral results suggest antidepressant effects and a potential to reduce the rewarding effects of ethanol and amphetamine-type drugs, while anxiety-related outcomes remain inconclusive. Ayahuasca also influences locomotor activity, so controlling for movement is important in behavioral tasks. Neurobiologically, ayahuasca affects brain structures involved in memory, emotion, and learning, and its effects involve pathways beyond the serotonergic system. Key gaps in ayahuasca research can still be addressed using animal models.