OPEN Foundation

Toxicology

Neurochemical and Behavioral Profiling in Male and Female Rats of the Psychedelic Agent 25I-NBOMe

Abstract

4-Iodo-2,5-dimethoxy-N-(2-methoxybenzyl)phenethylamine (25I-NBOMe), commonly called “N-Bomb,” is a synthetic phenethylamine with psychedelic and entactogenic effects; it was available on the Internet both as a legal alternative to lysergic acid diethylamide (LSD) and as a surrogate of 3,4-methylenedioxy-methamphetamine (MDMA), but now it has been scheduled among controlled substances. 25I-NBOMe acts as full agonist on serotonergic 5-HT2A receptors. Users are often unaware of ingesting fake LSD, and several cases of intoxication and fatalities have been reported. In humans, overdoses of “N-Bomb” can cause tachycardia, hypertension, seizures, and agitation. Preclinical studies have not yet widely investigated the rewarding properties and behavioral effects of this compound in both sexes. Therefore, by in vivo microdialysis, we evaluated the effects of 25I-NBOMe on dopaminergic (DA) and serotonergic (5-HT) transmissions in the nucleus accumbens (NAc) shell and core, and the medial prefrontal cortex (mPFC) of male and female rats. Moreover, we investigated the effect of 25I-NBOMe on sensorimotor modifications as well as body temperature, nociception, and startle/prepulse inhibition (PPI). We showed that administration of 25I-NBOMe affects DA transmission in the NAc shell in both sexes, although showing different patterns; moreover, this compound causes impaired visual responses in both sexes, whereas core temperature is heavily affected in females, and the highest dose tested exerts an analgesic effect prominent in male rats. Indeed, this drug is able to impair the startle amplitude with the same extent in both sexes and inhibits the PPI in male and female rats. Our study fills the gap of knowledge on the behavioral effects of 25I-NBOMe and the risks associated with its ingestion; it focuses the attention on sex differences that might be useful to understand the trend of consumption as well as to recognize and treat intoxication and overdose symptoms.

Miliano, C., Marti, M., Pintori, N., Castelli, M. P., Tirri, M., Arfè, R., & De Luca, M. A. (2019). Neurochemical and Behavioral Profiling in Male and Female Rats of the Psychedelic Agent 25I-NBOMe. Frontiers in Pharmacology10., 10.3389/fphar.2019.01406
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Locomotor effects of 3,4-methylenedioxymethamphetamine (MDMA) and its deuterated form in mice: psychostimulant effects, stereotypy, and sensitization

Abstract

Rationale

There is a renewed interest in the use of 3,4-methylenedioxymethamphetamine (MDMA) for treating psychiatric conditions. Although MDMA has entered phase II clinical trials and shows promise as an adjunct treatment, there is an extensive literature detailing the potential neurotoxicity and adverse neurobehavioral effects associated with MDMA use. Previous research indicates that the adverse effects of MDMA may be due to its metabolism into reactive catechols that can enter the brain and serve directly as neurotoxicants. One approach to mitigate MDMA’s potential for adverse effects is to reduce O-demethylation by deuterating the methylenedioxy ring of MDMA. There are no studies that have evaluated the effects of deuterating MDMA on behavioral outcomes.

Objectives

The purpose of the present study was to assess the motor-stimulant effects of deuterated MDMA (d2-MDMA) and compare them to MDMA in male mice.

Methods

Two experiments were performed to quantify mouse locomotor activity and to vary the drug administration regimen (single bolus administration or cumulative administration).

Results

The results of Experiments 1 and 2 indicate that d2-MDMA is less effective at eliciting horizontal locomotion than MDMA; however, the differences between the compounds diminish as the number of cumulative administrations increase. Both d2-MDMA and MDMA can elicit sensitized responses, and these effects cross-sensitize to the prototypical drug of abuse methamphetamine. Thus, d2-MDMA functions as a locomotor stimulant similar to MDMA, but, depending on the dosing regimen, may be less susceptible to inducing sensitization to stereotyped movements.

Conclusions

These findings indicate that d2-MDMA is behaviorally active and produces locomotor effects that are similar to MDMA, which warrant additional assessments of d2-MDMA’s behavioral and physiological effects to determine the conditions under which this compound may serve as a relatively safer alternative to MDMA for clinical use.
Berquist, M. D., Leth-Petersen, S., Kristensen, J. L., & Fantegrossi, W. E. (2020). Locomotor effects of 3, 4-methylenedioxymethamphetamine (MDMA) and its deuterated form in mice: psychostimulant effects, stereotypy, and sensitization. Psychopharmacology237(2), 431-442; https://doi.org/10.1007/s00213-019-05380-3

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Metabolism of lysergic acid diethylamide (LSD): an update.

Abstract

Lysergic acid diethylamide (LSD) is the most potent hallucinogen known and its pharmacological effect results from stimulation of central serotonin receptors (5-HT2). Since LSD is seen as physiologically safe compound with low toxicity, its use in therapeutics has been renewed during the last few years. This review aims to discuss LSD metabolism, by presenting all metabolites as well as clinical and toxicological relevance. LSD is rapidly and extensively metabolized into inactive metabolites; whose detection window is higher than parent compound. The metabolite 2-oxo-3-hydroxy LSD is the major human metabolite, which detection and quantification is important for clinical and forensic toxicology. Indeed, information about LSD pharmacokinetics in humans is limited and for this reason, more research studies are needed.
Libânio Osório Marta, R. F. (2019). Metabolism of lysergic acid diethylamide (LSD): an update. Drug metabolism reviews51(3), 378-387. https://doi.org/10.1080/03602532.2019.1638931
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Transformative Psychopharmacology: the Case of 5-Methoxy-N,N-Dimethyltryptamine

Abstract

Since the 2nd part of last century neo-shamanic rituals using mind-altering extracts from plants or animals have become increasingly popular in Europe and the USA. The first rituals coming to the west were based on drinking a special Amazonian tea, Ayahuasca, based on 2 different plants, with active compounds belonging to the class of the beta-carbolines (harmala alkaloids) and tryptamines. The use of such compounds will be described from the perspective of the transformative psychopharmacology: that part of psychopharmacology studying the use of psychoactive compounds to achieve a new balance, a transformation or healing and sometimes even leading to a cure. Examples of curing are meanwhile well documented, for instance the positive influence on drug abuse and addiction, alcoholism. The importance of the healing aspects of these rituals however are often neglected or overlooked. For users, these are key however. As medicine becomes more and more personalized and postmodern, it will be relevant to understand why patients and healthy people decide to participate in healing rituals based on psycho-active compounds. We will present the pharmacology, the transformative psychopharmacology, the effects and adverse events of 5-methoxy-N, N-dimethyltryptamine (5-MeO-DMT) and its place in postmodern medicine.

Jan M Keppel Hesselink (2019) Transformative Psychopharmacology: the Case of 5-Methoxy-N,N-Dimethyltryptamine. International Journal of Psychotherapy Practice and Research – 1(3):9-15., 10.14302/issn.2574-612X.ijpr-18-2503
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DARK Classics in Chemical Neuroscience: Atropine, Scopolamine, and Other Anticholinergic Deliriant Hallucinogens

Abstract

Anticholinergic drugs based on tropane alkaloids, including atropine, scopolamine, and hyoscyamine, have been used for various medicinal and toxic purposes for millennia. These drugs are competitive antagonists of acetylcholine muscarinic (M-) receptors that potently modulate the central nervous system (CNS). Currently used clinically to treat vomiting, nausea, and bradycardia, as well as alongside other anesthetics to avoid vagal inhibition, these drugs also evoke potent psychotropic effects, including characteristic delirium-like states with hallucinations, altered mood, and cognitive deficits. Given the growing clinical importance of anti-M deliriant hallucinogens, here we discuss their use and abuse, clinical importance, and the growing value in preclinical (experimental) animal models relevant to modeling CNS functions and dysfunctions.

Lakstygal, A., Kolesnikova, T., Khatsko, S., Zabegalov, K., Volgin, A., Demin, K., … & Kalueff, A. (2018). DARK classics in chemical neuroscience: atropine, scopolamine and other anticholinergic deliriant hallucinogens. ACS chemical neuroscience., 10.1021/acschemneuro.8b00615
 
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Pharmacokinetic And Pharmacodynamic Aspects Of Peyote And Mescaline: Clinical And Forensic Repercussions

Abstract

BACKGROUND:

Mescaline (3,4,5-trimethoxyphenethylamine), mainly found in the Peyote cactus (Lophophora williamsii), is one of the oldest known hallucinogenic agents that influence human and animal behavior, but its psychoactive mechanisms remain poorly understood.

OBJECTIVES:

This article aims to fully review pharmacokinetics and pharmacodynamics of mescaline, focusing on the in vivo and in vitro metabolic profile of the drug and its implications for the variability of response.

METHODS:

Mescaline pharmacokinetic and pharmacodynamic aspects were searched in books and in PubMed (U.S. National Library of Medicine) without a limiting period. Biological effects of other compounds found in peyote were also reviewed.

RESULTS:

Although its illicit administration is less common, in comparison with cocaine and Cannabis, it has been extensively described in adolescents and young adults, and licit consumption often occurs in religious and therapeutic rituals practiced by the Native American Church. Its pharmacodynamic mechanisms of action are primarily attributed to the interaction with the serotonergic 5-HT2A-C receptors, and therefore clinical effects are similar to those elicited by other psychoactive substances, such as lysergic acid diethylamide (LSD) and psilocybin, which include euphoria, hallucinations, depersonalization and psychoses. Moreover, as a phenethylamine derivative, signs and symptoms are consistent with a sympathomimetic effect. Mescaline is mainly metabolized into trimethoxyphenylacetic acid by oxidative deamination but several minor metabolites with possible clinical and forensic repercussions have also been reported.

CONCLUSION:

Most reports concerning mescaline were described in a complete absence of exposure confirmation, since toxicological analysis is not widely available. Addiction and dependence are practically absent and it is clear that most intoxications appear to be mild and are unlikely to produce life-threatening symptoms, which favors the contemporary interest in the therapeutic potential of the drugs of the class.

Dinis-Oliveira, R. J., Pereira, C. L., & Da Silva, D. D., (2018). Pharmacokinetic And Pharmacodynamic Aspects Of Peyote And Mescaline: Clinical And Forensic Repercussions. Current molecular pharmacology., 10.2174/1874467211666181010154139
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Blood pressure safety of subanesthetic ketamine for depression: A report on 684 infusions

Abstract

BACKGROUND:
The dissociative anesthetic agent ketamine is increasingly being utilized to treat depression, despite not having FDA (Food and Drug Administration) approval for this indication. There are many questions about the potential risks of this treatment and hence the proper setting and degree of monitoring required to ensure patient safety. There is limited data about the cardiovascular safety of ketamine when administered at subanesthetic doses to treat depression.
METHODS:
66 patients in the Department of Psychiatry at Emory University received a total of 684 ketamine infusions between 2014 and 2016. Ketamine was dosed at 0.5 mg/kg body weight and infused over 40 min. Blood pressure was measured every 10 min during the infusions and every 15 min thereafter.
RESULTS:
Mean age of the patients was 56.7 years, 87.9% had unipolar depression and 36.1% had essential hypertension. No infusions were discontinued due to instability of vital signs, adverse physiological consequences or acute psychotomimetic effects. The biggest increases in blood pressure were measured at 30 min (systolic 3.28 mmHg, diastolic 3.17 mmHg). Hypertensive patients had higher blood pressure peaks during the infusions. Blood pressures returned to baseline during post-infusion monitoring. There was no development of tolerance to the blood pressure elevating effects of ketamine between the first and sixth infusions.
LIMITATIONS:
This is a single site, retrospective analysis, of patients who were spontaneously seeking clinical care.
CONCLUSIONS:
The blood pressure changes observed when ketamine is administered over 40 min at 0.5 mg/kg for the treatment of depression are small, well tolerated and clinically insignificant.
Riva-Posse, P., Reiff, C. M., Edwards, J. A., Job, G. P., Galendez, G. C., Garlow, S. J., … & McDonald, W. M. (2018). Blood pressure safety of subanesthetic ketamine for depression: A report on 684 infusions. Journal of affective disorders236, 291-297. 10.1016/j.jad.2018.02.025
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Dark Classics in Chemical Neuroscience: 3,4-Methylenedioxymethamphetamine

Abstract

Better known as “ecstasy”, 3,4-methylenedioxymethamphetamine (MDMA) is a small molecule that has played a prominent role in defining the ethos of today’s teenagers and young adults, much like lysergic acid diethylamide (LSD) did in the 1960s. Though MDMA possesses structural similarities to compounds like amphetamine and mescaline, it produces subjective effects that are unlike any of the classical psychostimulants or hallucinogens and is one of the few compounds capable of reliably producing prosocial behavioral states. As a result, MDMA has captured the attention of recreational users, the media, artists, psychiatrists, and neuropharmacologists alike. Here, we detail the synthesis of MDMA as well as its pharmacology, metabolism, adverse effects, and potential use in medicine. Finally, we discuss its history and why it is perhaps the most important compound for the future of psychedelic science-having the potential to either facilitate new psychedelic research initiatives, or to usher in a second Dark Age for the field.

Dunlap, L. E., Andrews, A. M., & Olson, D. E. (2018). Dark classics in chemical neuroscience: 3, 4-Methylenedioxymethamphetamine. ACS chemical neuroscience9(10), 2408-2427., 10.1021/acschemneuro.8b00155
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Cardiac arrest after ibogaine intoxication

Abstract

Ibogaine is a psychoactive herbal medication with alleged antiaddiction properties. We report a case of ibogaine intoxication mimicking Long-QT syndrome resulting in ventricular flutter and nearby cardiac arrest. A 61-year-old man experienced massive QT prolongation and ventricular flutter at a rate of 270 beats per minute requiring defibrillation after ingestion of a large dose of Ibogaine. The ingested dose of 65-70 mg/kg represents the highest survived ibogaine dose reported to date. As a result of the long plasma half-life of ibogaine, it took 7 days for the patient’s QT interval to normalize.

Steinberg, C., & Deyell, M. W. (2018). Cardiac arrest after ibogaine intoxication. Journal of arrhythmia34(4), 455-457.,  10.1002/joa3.12061

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Key interindividual determinants in MDMA pharmacodynamics

Abstract

MDMA, 3,4-methylenedioxymethamphetamine, is a synthetic phenethylamine derivative with structural and pharmacological similarities to both amphetamines and mescaline. MDMA produces characteristic amphetamine-like actions (euphoria, well-being), increases empathy, and induces pro-social effects that seem to motivate its recreational consumption and provide a basis for its potential therapeutic use. Areas covered: The aim of this review is to present the main interindividual determinants in MDMA pharmacodynamics. The principal sources of pharmacodynamic variability are reviewed, with special emphasis on sex-gender, race-ethnicity, genetic differences, interactions, and MDMA acute toxicity, as well as possible therapeutic use. Expert opinion: Acute MDMA effects are more pronounced in women than they are in men. Very limited data on the relationship between race-ethnicity and MDMA effects are available. MDMA metabolism includes some polymorphic enzymes that can slightly modify plasma concentrations and effects. Although a considerable number of studies exist about the acute effects of MDMA, the small number of subjects in each trial limits evaluation of the different interindividual factors and does not permit a clear conclusion about their influence. These issues should be considered when studying possible MDMA therapeutic use.
Papaseit, E., Torrens, M., Pérez-Mañá, C., Muga, R., & Farré, M. (2018). Key interindividual determinants in MDMA pharmacodynamics. Expert opinion on drug metabolism & toxicology, (just-accepted). 10.1080/17425255.2018.1424832
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30 April - Q&A with Rick Strassman

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