Biology subjects

Yonamine, M.

Publications and source records attributed to Yonamine, M..

3 recordsLinked to original sources

bioRxiv2024

Effect Of Ayahuasca on Experimental Models of Ethanol Addiction and Immunohistochemistry Analysis in Rodents

BackgroundAyahuasca, a psychoactive Amazonian preparation, is increasingly studied for substance-use disorders. ObjectivesInvestigate whether oral lyophilised-ayahuasca attenuates ethanol-induced conditioned place preference (CPP) in mice and alters {Delta}FosB expression in nucleus accumbens (NAc). MethodsMale Swiss mice received water or ayahuasca (130-1950 mg/kg, p.o.) 30 min before each of eight ethanol pairings (2g/kg i.p.) in a CPP paradigm. A separate cohort underwent acute toxicology (650-5000mg/kg) with behavioural-observation and rotarod. Alkaloids were quantified by LC-MS/MS. {Delta}FosB-immunoreactive nuclei were counted in NAc 24h after the CPP post-test. ResultsAlkaloids levels were within traditional ranges. High-dose ayahuasca(5000 mg/kg) produced transient-serotonergic-syndrome-like signs and rotarod locomotor-deficit; lower doses did not express toxicity. Ethanol produced a moderate-CPP in controls({Delta}Time{approx}+60s), whereas ayahuasca-pretreatment abolished preference at all doses({Delta}Time within{+/-}7s). One-way ANOVA on {Delta}Time showed a robust-Treatment effect(F(3,36)=8.83, p=0.00016); Tukey tests: control differed from each ayahuasca group (all p<0.05), with no differences among ayahuasca doses. {Delta}FosB density did not differ among groups(p>0.05). ConclusionsAyahuasca was well tolerated at ceremonies-equivalent doses and blocked ethanol-induced-CPP across all doses, while {Delta}FosB levels in NAc were unchanged at 24h. Limitations on the CPP baseline and {Delta}FosB results may limit sensitivity, generalisability and interpretation. Findings provide preliminary evidence that ayahuasca-pretreatment may blunt ethanol-context preference, reinforcing the need of replication with stronger reward baselines, naive controls and complementary molecular markers.

pharmacology and toxicology↗

bioRxiv2020

Molecular and functional basis of a novel Amazonian Dark Earth Esterase 1 (Ade1) with hysteresis behavior and quorum-quenching activity

Amazon Dark Earth (ADE) soil is rich in organic compounds and its fertility has been associated with a high diversity of microorganisms. Herein, we investigate the biochemical and functional features of a novel esterase, Ade1, obtained from a metagenomic library of Amazonian Dark Earth soils of the Amazonian Rainforest, in Brazil. The esterases cleave ester bonds to form a carboxylic and an alcohol group. Esterases and lipases are enzymes found in almost all living organisms, demonstrating their biological relevance. We reported that Ade1 belongs to an /{beta}-hydrolase superfamily. We suggest that Ade1 is a moonlighting enzyme with hysteresis behavior and quorum-quenching activity, which may play a key role in the metabolism of a Gram-negative proteobacteria. In addition, molecular dynamics simulations reveal that the hysteresis behavior is directly associated with structural properties of the cap domain. Our findings reveal details of the molecular basis, catalytic and structural mechanisms of a novel /{beta}-hydrolase, which may be applied to other esterases of biotechnological, food, and/or pharmaceutical interest. O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

biochemistry↗

bioRxiv2017

Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomised placebo-controlled trial

Major Depressive Disorder affects about 350 million people worldwide, and about one-third of the patients are considered treatment-resistant. Furthermore, available antidepressants take usually two weeks for the onset of their antidepressant effect. Recent open label trials show that psychedelics, such as ayahuasca and psilocybin, hold promise as fast-onset antidepressants. Although promising, these studies were not controlled for the placebo effect. To address this issue, and to further test the antidepressant effects of ayahuasca, we conducted a parallel arm, double-blind randomised placebo-controlled trial, in patients with treatment-resistant major depression. Thirty-five patients with treatment-resistant major depression received a single dose of ayahuasca or placebo. We measured as primary outcome the change in the Hamilton Depression Rating scale (HAM-D) seven days after the dosing session, and as secondary outcomes the changes in Montgomery-[A]sberg Depression Rating Scale (MADRS), and response rates at one day (D1), two days (D2) and seven days (D7) after dosing, and remission rates at D7. This study is registered with http://clinicaltrials.gov (NCT02914769). We observed robust evidence of rapid antidepressant effects of a single dosing session with ayahuasca when compared to placebo. HAM-D scores at D7 were significantly lower in patients treated with ayahuasca than in those treated with placebo (p=0{middle dot}019; Cohens d=0{middle dot}98). MADRS scores were significantly reduced in the ayahuasca group compared to the placebo group at all endpoints (at D1 and D2, p=0{middle dot}04; at D7, p<0{middle dot}0001). Between-group effect sizes increased from D1 to D7 (D1: Cohens d=0{middle dot}84; D2: Cohens d=0{middle dot}84; D7: Cohens d=1{middle dot}49). Response rates were high for both groups at D1 and D2, and were significantly higher in the ayahuasca group only at D7 (64% vs. 27%; OR = 4{middle dot}95; p = 0{middle dot}04; NNT = 2{middle dot}66). Remission rate was not significantly different between groups. Our study provides new evidence of rapid antidepressant effects of ayahuasca for treatment-resistant major depression.

clinical trials↗