Evaluation of the Cytotoxicity of Ayahuasca Beverages

Abstract

Ayahuasca is a beverage consumed at shamanic ceremonies and currently has gained popularity on recreational scenarios. It contains beta-carboline alkaloids and N,N-dimethyltryptamine, which possesses hallucinogenic effects. Only a few studies have elicited the psychoactive effects and the dose of such compounds on neurological dopaminergic cells or animals. In this work, we aimed to study the cytotoxic effects of these compounds present in ayahuasca beverages and on five different teas (Banisteriopsis caapi, Psychotria viridis, Peganum harmala, Mimosa tenuiflora and Dc Ab (commercial name)) preparations on dopaminergic immortalized cell lines. Moreover, a characterization of the derivative alkaloids was also performed. All the extracts were characterized by chromatographic systems and the effect of those compounds in cell viability and total protein levels were analyzed in N27 dopaminergic neurons cell line. This is the first article where cytotoxicity of ayahuasca tea is studied on neurological dopaminergic cells. Overall, results showed that both cell viability and protein contents decreased when cells were exposed to the individual compounds, as well as to the teas and to the two mixtures based on the traditional ayahuasca beverages.

Keywords: N,N-dimethyltryptamine; ayahuasca; beta-carboline alkaloids; cytotoxicity; mesencephalic dopaminergic neurons.

Figure 1

Chromatogram of Psychotria viridis.

Figure 2

(a) Structures of the tryptamine alkaloids detected from the methanolic extracts. (b) Extracted ion chromatograms (EICs) at m/z 205.1341. A complete chromatographic separation was observed for bufotenine (5-HO-DMT) and its structural isomer, psilocin (4-HO-DMT). (c) Detail of the main fragment ions and the fragmentation pathway proposed.

Figure 3

(a) Structures of the beta-carboline alkaloids detected from the methanolic extracts. (b–d). Detail of the main fragment ions and the fragmentation pathways proposed.

Figure 4

The effect of 0.2% of DMSO on N27 cell viability (24 h). The highest concentration used as a vehicle in the evaluation of the respective compounds was 0.2% of DMSO (Control—untreated cells (100 ± 0.00), DMT (1 µM; 84.86 ± 6.29), HMN (10 µM; 78.04 ± 20.13), HML (80 µM; 91.40 ± 5.89) and THH (10 µM; 90.49 ± 4.36); n = 3, values are shown as mean ± SEM; no significant difference was observed when performing ANOVA followed by Dunnett’s multiple comparison test).

Figure 5

The effects of (A) HMN, (B) HML, (C) THH and (D) DMT on N27 cell line viability (24 h), (n = 3, values are shown as mean ± SEM ** indicates values that are significantly different from control p < 0.01, one-way analysis of variance followed by Bonferroni’s multiple comparison test). CTR: Control.

Figure 6

The effects of P. harmala (16 and 80 µM), B. caapi (2 and 10 µM), M. tenuiflora (1 µM), P. viridis (1 µM) and Dc Ab (2 and 10 µM) on N27 cell viability (24 h); CTR—control, (n = 3, values are shown as mean ± SEM ** indicates values that are significantly different from control p < 0.01, one-way analysis of variance followed by Dunnett’s multiple comparison test).

Figure 7

The effects of tea plant extracts mixtures (P. viridis plus B. caapi and P. viridis plus P. harmala) on N27 cell viability (n = 3). The presented values are presented as mean ± SEM. ** indicates values that are significantly different from control (p < 0.05, one-way analysis of variance (ANOVA)). CTR—control.

Figure 8

Protein levels when N27 cells are exposed during 24 h to HMN, THH, HML and DMT; CTR (control with untreated cells; 0.59 ± 0.08), HMN 0.00064 µM (0.65 ± 0.04), HMN 10 µM (0.19 ± 0.02), THH 0.00064 µM (0.56 ± 0.09), THH 10 µM (0.32 ± 0.05), HML 0.00512 µM (0.59 ± 0.04) and HML 10 µM (0.14 ± 0.0006); DMT 0.0008 µM (0.73 ± 0.02); DMT 1 µM (0.59 ± 0.03). n = 3, values are shown as mean ± SEM * indicates values that are significantly different from control p < 0.05, one-way analysis of variance followed by Dunnett’s multiple comparison test. CTR—control.