MDMA ("ecstasy") and neurotoxicity

Psychedelics in Psychiatry: Neuroplastic, Immunomodulatory, and Neurotransmitter Mechanisms

Mounting evidence suggests safety and efficacy of psychedelic compounds as potential novel therapeutics in psychiatry. Ketamine has been approved by the Food and Drug Administration in a new class of antidepressants, and 3,4-methylenedioxymethamphetamine (MDMA) is undergoing phase III clinical trials for post-traumatic stress disorder. Psilocybin and lysergic acid diethylamide (LSD) are being investigated in several phase II and phase I clinical trials. Hence, the concept of psychedelics as therapeutics may be incorporated into modern society. Here, we discuss the main known neurobiological therapeutic mechanisms of psychedelics, which are thought to be mediated by the effects of these compounds on the serotonergic (via 5-HT_2A and 5-HT_1A receptors) and glutamatergic [via N-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors] systems. We focus on 1) neuroplasticity mediated by the modulation of mammalian target of rapamycin-, brain-derived neurotrophic factor-, and early growth response-related pathways; 2) immunomodulation via effects on the hypothalamic-pituitary-adrenal axis, nuclear factor ĸB, and cytokines such as tumor necrosis factor-α and interleukin 1, 6, and 10 production and release; and 3) modulation of serotonergic, dopaminergic, glutamatergic, GABAergic, and norepinephrinergic receptors, transporters, and turnover systems. We discuss arising concerns and ways to assess potential neurobiological changes, dependence, and immunosuppression. Although larger cohorts are required to corroborate preliminary findings, the results obtained so far are promising and represent a critical opportunity for improvement of pharmacotherapies in psychiatry, an area that has seen limited therapeutic advancement in the last 20 years. Studies are underway that are trying to decouple the psychedelic effects from the therapeutic effects of these compounds. SIGNIFICANCE STATEMENT: Psychedelic compounds are emerging as potential novel therapeutics in psychiatry. However, understanding of molecular mechanisms mediating improvement remains limited. This paper reviews the available evidence concerning the effects of psychedelic compounds on pathways that modulate neuroplasticity, immunity, and neurotransmitter systems. This work aims to be a reference for psychiatrists who may soon be faced with the possibility of prescribing psychedelic compounds as medications, helping them assess which compound(s) and regimen could be most useful for decreasing specific psychiatric symptoms.

Dissemination of Erroneous Research Findings and Subsequent Retraction in High-Circulation Newspapers: A Case Study of Alleged MDMA-Induced Dopaminergic Neurotoxicity in Primates

Ensuring the public is informed of retractions has proven difficult for the scientific community. While it is possible that newspapers focus differential attention on publication of scientific articles and their subsequent retractions, this topic has received minimal attention from researchers. To learn more, we analyzed newspaper coverage of the high-profile 2002 article Severe dopaminergic neurotoxicity in primates after a common recreational dose regimen of MDMA ("ecstasy") and its retraction in a case study. We searched the 50 largest American newspapers with available online archives for stories about the article's publication and retraction. Of the 50 newspapers, 26 (52%) covered the article's publication and 20 (40%) its retraction. Six of the 50 newspapers (12%) published stories on the article's retraction without covering its initial publication. Of the 26 newspapers covering the article's publication, only 14 (54%) covered its retraction. Stories about the retraction were balanced, but shorter than those on the article's publication and often lacking in context and detail. While the decrease in coverage of the article's retraction was moderate among the entire sample, the much lower retraction coverage in newspapers that had already covered the article's publication is concerning and emphasizes the need for increased media coverage of retractions.

Targeting the 5-HT system: Potential side effects

Targeting the serotonin (5-HT) system is no simple task: there are at least 15 5-HT receptors, in addition to a number of transporters and metabolizing enzymes. Multiple 5-HT receptor variants exist due to genetic variations and/or post translational modifications, splice variants or editing variants. Some receptors may form homo and heteromers. The 5-HT system is targeted by multiple drugs to treat a variety of diseases. Given the homology amongst the 5-HT and neighbouring receptor classes, only few drugs are actually selective for a single target. In fact, many 5-HT drugs act on a combination of targets, i.e. several receptors and/or transporters or enzymes. For instance, a number of antidepressants or antipsychotics act on 5-HT and other transmitter systems. Recently developed drugs may show target selectivity by design, based on the current state of knowledge, whereas many older compounds hit multiple targets since they were developed using phenotypic screens, as was done well into the 1980's. Ergot analogues, antipsychotics or antidepressants, fall into this category. As our knowledge developed over the last 25-30 years, some targets have very well-defined liabilities: for instance, 5HT_2B or 5-HT_2A receptor agonists, will produce valvulopathies or hallucinations, respectively, whereas 5-HT₃ receptor antagonists, may lead to constipation. This short review will be limited in scope as there are multiple targets and even more compounds to discuss. This article is part of the special issue entitled 'Serotonin Research: Crossing Scales and Boundaries'.

MDMA Is Not Ecstasy: The Production of Pharmaceutical Safety through Documents in Clinical Trials

Nonprofit efforts to develop ±3,4-methylenedioxymethamphetamine (MDMA)-better known as the street drug Ecstasy-as a prescription pharmaceutical provide the opportunity to examine recent theorizations of pharmaceuticals as fluid objects transformed in new informational and material environments. Drawing from ethnographic research, this article interrogates MDMA researchers' own distinction between MDMA and the street drug Ecstasy. While researchers maintain that pure MDMA is distinct from Ecstasy, this article argues that the difference between the two hangs not on a distinction in substance, but on a distinction in safety that must be produced through the trial. This article tracks the production of safety through the inter-connected work of clinical documents, which manage both which bodies are allowed to absorb the drug and which bodily events count as effects. MDMA's safety emerges from the careful management of relations through these documentary practices.

Current Perspective on MDMA-Assisted Psychotherapy for Posttraumatic Stress Disorder

The present paper discusses the current literature with regard to substance-assisted psychotherapy with Methylenedioxymethamphetamine (MDMA) for posttraumatic stress disorder (PTSD). The aim of the paper is to give a comprehensive overview of the development from MDMA's early application in psychotherapy to its present and future role in the treatment of PTSD. It is further attempted to increase the attention for MDMA's therapeutic potential by providing a thorough depiction of the scientific evidence regarding its theorized mechanism of action and potential harms of its application in the clinical setting (e.g., misattribution of therapeutic gains to medication instead of psychological changes). Empirical support for the use of MDMA-assisted psychotherapy, including the randomized, double-blind, placebo-controlled trails that have been conducted since 2008, is discussed. Thus far, an overall remission rate of 66.2% and low rates of adverse effects have been found in the six phase two trials conducted in clinical settings with 105 blinded subjects with chronic PTSD. The results seem to support MDMA's safe and effective use as an adjunct to psychotherapy. Even though preliminary studies may look promising, more studies of its application in a psychotherapeutic context are needed in order to establish MDMA as a potential adjunct to therapy.

Legal highs: staying on top of the flood of novel psychoactive substances

There has been growing clinical, public, and media awareness and concern about the availability and potential harmfulness of so-called 'legal highs', which are more appropriately called new or novel psychoactive substances (NPS). A cat-and-mouse process has emerged wherein unknown chemists and laboratories are producing new, and as yet nonproscribed, compounds for human consumption; and as soon as they are banned, which they inevitably are, slightly modified analogues are produced to circumvent new laws. This rapidly changing environment, 81 new substances were identified in 2013 alone, has led to confusion for clinicians, psychopharmacologists, and the public at large. Our difficulties in keeping up with the process has had a two-fold negative effect: the danger of ignoring what is confusing; and the problem that some of the newer synthesized compounds appear ever more potent. This review aims to circumscribe a quick moving and growing field, and to categorize NPS into five major groups based upon their 'parent' compounds: stimulants similar to cocaine, amphetamines and ecstasy; cannabinoids; benzodiazepine based drugs; dissociatives similar to ketamine and phencyclidine (PCP); and those modelled after classic hallucinogens such as LSD and psilocybin. Pharmacodynamic actions, subjective and physical effects, harmfulness, risk of dependency and, where appropriate, putative clinical potentials are described for each class. Clinicians might encounter NPS in various ways: anecdotal reportage; acute intoxication; as part of a substance misuse profile; and as a precipitant or perpetuating factor for longer-term physical and psychological ill health. Current data are overall limited, and much of our knowledge and treatment strategies are based upon those of the 'parent' compound. There is a critical need for more research in this field, and for professionals to make themselves more aware of this growing issue and how it might affect those we see clinically and try to help: a brave new world of so-called 'psychonauts' consuming NPS will also need informed 'psychotherapeutonauts'. The paper should serve as a primer for clinicians and interested readers, as well as provide a framework into which to place the new substances that will inevitably be synthesized in the future.

Transcriptomic configuration of mouse brain induced by adolescent exposure to 3,4-methylenedioxymethamphetamine

The amphetamine derivative (+/-)-3,4-methylenedioxymethamphetamine (MDMA or ecstasy) is a synthetic amphetamine analogue used recreationally to obtain an enhanced affiliative emotional response. MDMA is a potent monoaminergic neurotoxin with the potential to damage brain serotonin and/or dopamine neurons. As the majority of MDMA users are young adults, the risk that users may expose the fetus to MDMA is a concern. However, the majority of studies on MDMA have investigated the effects on adult animals. Here, we investigated whether long-term exposure to MDMA, especially in adolescence, could induce comprehensive transcriptional changes in mouse brain. Transcriptomic analysis of mouse brain regions demonstrated significant gene expression changes in the cerebral cortex. Supervised analysis identified 1028 genes that were chronically dysregulated by long-term exposure to MDMA in adolescent mice. Functional categories most represented by this MDMA characteristic signature are intracellular molecular signaling pathways of neurotoxicity, such as, the MAPK signaling pathway, the Wnt signaling pathway, neuroactive ligand-receptor interaction, long-term potentiation, and the long-term depression signaling pathway. Although these resultant large-scale molecular changes remain to be studied associated with functional brain damage caused by MDMA, our observations delineate the possible neurotoxic effects of MDMA on brain function, and have therapeutic implications concerning neuro-pathological conditions associated with MDMA abuse.

Long-term effects of MDMA (Ecstasy) on the human central nervous system revealed by visual evoked potentials

Several studies indicate long-term cognitive impairment of MDMA (ecstasy) users. In the present study we attempted to establish whether electrophysiological correlates of low-level cognitive processes present a long-term alteration, dependent on the level of use of ecstasy. We addressed this issue by investigating amplitude and latency of VEPs related to a very simple discrimination task involving sustained attention (arousal). Eight heavy-MDMA users, eight moderate-MDMA users and 18 drug-free control subjects were asked to discriminate whether the digit at the centre of the screen was 1 or 2. None of the subjects (except one) had used MDMA in the 6 months previous testing. We measured psychophysical performance and EEG, recorded in Oz and Fz during task execution. The heavy-MDMA users made significantly more errors than the other two groups (p < .05). Moreover, they presented reduced amplitude but not latency of VEPs in both Oz and Fz. The effect in Oz is present in P200 (for heavy users only, p < .05) and in P300 components (for both MDMA groups; heavy users: p < .001, moderate users: p < .0.5). In Fz, the amplitude effect is present in N250 (for heavy users only, p < .05) and in P300 components (for both MDMA groups; heavy users: p < .05, moderate users: p < .05). The three groups do not differ in early components, reflecting low-level processing. These results provide evidence of long-term electrophysiological abnormality displayed by ecstasy users and agree with the suggestion that even typical recreational doses of ecstasy are sufficient to cause long-term altered cortical activity in humans.

Party drugs: properties, prevalence, patterns, and problems

This review summarizes the latest literature on "party" or "club" drugs, defined as MDMA, GHB, ketamine, and Rohypnol, as published from 2002 to early 2005. Club drugs have been categorized as being used at raves and dance parties. The literature shows that each drug has different properties, users, and settings. Each drug has different adverse effects and requires different acute care protocols. Although these drugs were identified early, scientific information about them, including the toxicological tests to identify them, is still evolving. Increasing numbers of studies on the short- and long-term effects of these drugs on humans are being published, but because of limitations on research using human subjects, they may not always be as rigorous as desired and can be cited by drug users to discredit findings of harm. The lack of research-based information on these drugs has led to the emergence of web sites that may or may not provide accurate data. Evaluated chemical dependency treatment protocols using the latest research for each of these different drugs are needed.

Fraud, errors and gamesmanship in experimental toxicology

We expect moral behaviour from scientists. Morality implies being a good person and being good at one's profession. The general view appears to be that the vast majority of scientists aim to achieve these high standards. Science prides itself on the 'self-correcting' mechanism in the scientific method, namely the requirement to reproduce findings before they are taken seriously. However, when findings are related to the adverse effects of chemicals there are several features that make this less effective than in some other fields of science. First, is the perception that everyone is exposed to chemicals and observations about chemical danger are immediately applicable to many people. Second, it is often easy to summarize adverse findings in attention-getting headlines seen by the lay public before the slow process of replication and interpretation has time to work. Third, most regulatory toxicology studies on a particular compound are only done once to minimise cost and the use of animals. Finally, the question posed about chemicals--are they safe?--is easy to ask but more difficult to test with appropriate studies. Fabrication of data in regulatory studies was found to occur in several contract laboratories in the 1960s and this lead directly to the introduction of Good Laboratory Practice regulations. Now studies submitted for regulatory purposes must comply with GLP regulations and this has virtually eliminated flawed studies due to fraudulent or careless behaviour. It is possible to discern different ways in which the expected standards have not been met. The first is in the intention of the work. Thus reports that the Roodeplaats Research Laboratory in South Africa was seeking to identify toxins that would kill without trace is an example where the intention is unacceptable. The second is in the conduct of the studies. Here the examples of William McBride and Michael Briggs who falsified data are pertinent. The example of the retraction of reports on the toxicity of ecstasy because the wrong compound had been administered indicates a degree of carelessness in the conduct of the study. The third is in the design and interpretation of studies. The report that genetic modification per se could render potatoes toxic has been criticised because of the inappropriate design and interpretation of the studies. Finally, that the reports of studies are biased because of conflicts of interest. Journals often require a declaration that the author has no financial conflict of interest. However, there are many other conflicts of interest with just as large an impact on the author's impartiality which are omitted from consideration. Gamesmanship has also entered the practice of toxicology, for example where strong assertions about conflict of interest are used to justify particular points of view. The main casualty from fraud, errors and gamesmanship is the perceived status of science itself. It is only gamesmanship that is on the increase. The remedies for these activities are explored.