RETRACTED: Severe dopaminergic neurotoxicity in primates after a common recreational dose regimen of MDMA ("ecstasy")

Methylenedioxymethamphetamine (MDMA)-Assisted Therapy in Hawaii: A Brief Review

The Food and Drug Administration (FDA) granted breakthrough therapy status to 3,4-methyl​enedioxy​methamphetamine-assisted therapy (MDMA-AT) in 2017 due to preliminary evidence supporting its efficacy and safety in treating post-traumatic stress disorder (PTSD). A series of six phase-II clinical trials studying MDMA-AT for treatment-resistant PTSD found that 54% of MDMA-AT full-dose participants no longer met the diagnosis of PTSD after two MDMA sessions, compared to 23% in the control group. In the first phase-III clinical trial, 67% no longer met the criteria for PTSD after three sessions. The effects are durable, with 67% no longer diagnosable after one year and 74% at nearly four years. The MDMA-AT is being fast-tracked for potential FDA approval by 2023. In 2021, Hawaii’s Senate Bill 738 unsuccessfully proposed that psilocybin be removed from the Schedule I controlled substances list due to its clinical efficacy for major depressive disorder. Methyl​enedioxy​methamphetamine is also a Schedule I controlled substance and has proven to be a treatment option that could potentially benefit the people of Hawaii.

Debunking the myth of 'Blue Mondays': No evidence of affect drop after taking clinical MDMA

BACKGROUND

Incorporating 3,4-methylenedioxymethamphetamine (MDMA) as an adjunct to psychotherapy has shown promise in recent years for treating various mental health conditions, particularly those involving trauma. However, concerns about declines in mood and cognition during the days following dosing, also known as 'Blue Mondays', have been raised as limitations to its clinical use. Although these changes have been well-documented among recreational users, there are critical confounds to these reports that limit generalizability to clinically administered MDMA.

AIMS

Here, we aimed to evaluate the evidence basis for the negative side effects associated with MDMA as well as inform our understanding of the drug's post-acute effects in a clinical context with an open-label study.

METHODS

The current open-label study examined MDMA therapy for alcohol use disorder (AUD; N = 14) and measured mood, sleep quality, illicit MDMA consumption and anecdotal reports after the acute drug effects had worn off.

RESULTS

Participants maintained a positive mood during the week following drug administration in a clinical context. Relative to baseline, self-reported sleep quality improved at the 3- and 6-month follow-ups. Finally, no participants reported using or desiring to use illicit MDMA, and the anecdotal reports indicated that they perceived the treatment favourably.

CONCLUSION

The results support the overall safety and tolerability of clinically administered MDMA and, importantly, suggest that the 'come downs' previously associated with the substance may be explained by confounds in research relating to the illicit sourcing of the drug and specific environmental setting for recreational consumption.

MDMA related neuro-inflammation and adenosine receptors

3,4-methylenedioxymethamphetamine (MDMA) is a world-wide abused psychostimulant, which has the neurotoxic effects on dopaminergic and serotonergic neurons in both rodents and non-human primates. Adenosine acts as a neurotransmitter in the brain through the activation of four specific G-protein-coupled receptors and it acts as a neuromodulator of dopamine neurotransmission. Recent studies suggest that stimulation of adenosine receptors oppose many behavioral effects of methamphetamines. This review summarizes the specific cellular mechanisms involved in MDMA neuroinflammatory effects, along with the protective effects of adenosine receptors.

Hallucinogens in Mental Health: Preclinical and Clinical Studies on LSD, Psilocybin, MDMA, and Ketamine

A revamped interest in the study of hallucinogens has recently emerged, especially with regard to their potential application in the treatment of psychiatric disorders. In the last decade, a plethora of preclinical and clinical studies have confirmed the efficacy of ketamine in the treatment of depression. More recently, emerging evidence has pointed out the potential therapeutic properties of psilocybin and LSD, as well as their ability to modulate functional brain connectivity. Moreover, MDMA, a compound belonging to the family of entactogens, has been demonstrated to be useful to treat post-traumatic stress disorders. In this review, the pharmacology of hallucinogenic compounds is summarized by underscoring the differences between psychedelic and nonpsychedelic hallucinogens as well as entactogens, and their behavioral effects in both animals and humans are described. Together, these data substantiate the potentials of these compounds in treating mental diseases.

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.

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.

Minocycline attenuates 3,4-methylenedioxymethamphetamine-induced hyperthermia in the rat brain

Hyperthermia is most dangerous clinical symptom of acute MDMA administration, and a key factor related to potentially life-threatening MDMA-induced complications. MDMA induces a consistently faster onset of brain hyperthermia when compared to a delayed and moderate hyperthermia in the body, and the most harmful effects of MDMA are related to its modulation of neural functions. The primary focus of this study was to investigate the effects of minocycline, a centrally acting tetracycline derivative on MDMA-induced brain hyperthermia at high ambient temperature. However, we also simultaneously recorded body temperature, heart rate, and locomotor activity changes, allowing us to gain a better understanding of the mechanisms underlying the MDMA-induced hyperthermic response. We also investigated the effects of MDMA at normal ambient temperature to provide further evidence as to the importance of environmental factors on the intensity of MDMA's temperature effects. At normal ambient temperature, MDMA (10 mg/kg, i.p.) induced a significant brain and body hypothermia for the first 90 min following drug administration, and significantly increased heart rate and locomotor activity compared to saline controls. At high ambient temperature however, MDMA (10 mg/kg, i.p.) induced a robust and extended brain and body hyperthermia, as well as significantly increased heart rate and locomotor activity. A 3-day minocycline (50 mg/kg, i.p.) pre-treatment significantly attenuated MDMA-induced increases in brain temperature, body temperature, heart rate, and locomotor activity. Our findings indicate that minocycline is more effective in attenuating the exacerbated MDMA-induced hyperthermic response in the brain compared to the body at high ambient temperature.

Dark Classics in Chemical Neuroscience: 3,4-Methylenedioxymethamphetamine

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.

Chronic administration of amphetamines disturbs development of neural progenitor cells in young adult nonhuman primates

The detrimental effects of amphetamines on developmental stages of NPCs are limited to rodent brain and it is not known if these effects occur in nonhuman primates which are the focus of the current investigation. Young adult rhesus macaques either experienced MDMA only, a combination of amphetamines (MDMA, MDA and methamphetamine) or no amphetamines (controls) and hippocampal tissue was processed for immunohistochemical analysis.Quantitative stereological analysis showed that intermittent exposure to MDMA or the three amphetamines over 9.6 months causes >80% decrease in the number of Ki-67 cells (actively dividing NPCs) and >50% decrease in the number of NeuroD1 cells (NPCs that have attained a neuronal phenotype). Co-labeling analysis revealed distinct, actively dividing hippocampal NPCs in the subgranular zone of the dentate gyrus that were in transition from stem-like radial glia-like cells (type-1) to immature transiently amplifying neuroblasts (type-2a, type-2b, and type-3).MDMA-alone and the combination reduced the number of dividing type-1 and type-3 NPCs and cells that were not NPCs. These data indicate that amphetamines interfere with the division and migration of NPCs. Notably, the reduction in the number of NPCs and immature neurons were not associated with changes in cell death (via apoptosis) or granule cell neuron numbers, indicating that amphetamines selectively affected the generation and maturation of newly born granule cell neurons. In sum, our findings suggest that alterations in the cellular composition in the dentate gyrus during chronic exposure to amphetamines can effect neuroplasticity in the hippocampus and influence functional properties of hippocampal neurons.

Progress and promise for the MDMA drug development program

Pharmacotherapy is often used to target symptoms of posttraumatic stress disorder (PTSD), but does not provide definitive treatment, and side effects of daily medication are often problematic. Trauma-focused psychotherapies are more likely than drug treatment to achieve PTSD remission, but have high dropout rates and ineffective for a large percentage of patients. Therefore, research into drugs that might increase the effectiveness of psychotherapy is a logical avenue of investigation. The most promising drug studied as a catalyst to psychotherapy for PTSD thus far is 3,4-methylenedioxymethamphetamine (MDMA), commonly known as the recreational drug "Ecstasy." MDMA stimulates the release of hormones and neurochemicals that affect key brain areas for emotion and memory processing. A series of recently completed phase 2 clinical trials of MDMA-assisted psychotherapy for treatment of PTSD show favorable safety outcomes and large effect sizes that warrant expansion into multi-site phase 3 trials, set to commence in 2018. The nonprofit sponsor of the MDMA drug development program, the Multidisciplinary Association for Psychedelic Studies (MAPS), is supporting these trials to explore whether MDMA, administered on only a few occasions, can increase the effectiveness of psychotherapy. Brain imaging techniques and animal models of fear extinction are elucidating neural mechanisms underlying the robust effects of MDMA on psychological processing; however, much remains to be learned about the complexities of MDMA effects as well as the complexities of PTSD itself.

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.

Monoamine reuptake inhibitors in Parkinson's disease

The motor manifestations of Parkinson's disease (PD) are secondary to a dopamine deficiency in the striatum. However, the degenerative process in PD is not limited to the dopaminergic system and also affects serotonergic and noradrenergic neurons. Because they can increase monoamine levels throughout the brain, monoamine reuptake inhibitors (MAUIs) represent potential therapeutic agents in PD. However, they are seldom used in clinical practice other than as antidepressants and wake-promoting agents. This review article summarises all of the available literature on use of 50 MAUIs in PD. The compounds are divided according to their relative potency for each of the monoamine transporters. Despite wide discrepancy in the methodology of the studies reviewed, the following conclusions can be drawn: (1) selective serotonin transporter (SERT), selective noradrenaline transporter (NET), and dual SERT/NET inhibitors are effective against PD depression; (2) selective dopamine transporter (DAT) and dual DAT/NET inhibitors exert an anti-Parkinsonian effect when administered as monotherapy but do not enhance the anti-Parkinsonian actions of L-3,4-dihydroxyphenylalanine (L-DOPA); (3) dual DAT/SERT inhibitors might enhance the anti-Parkinsonian actions of L-DOPA without worsening dyskinesia; (4) triple DAT/NET/SERT inhibitors might exert an anti-Parkinsonian action as monotherapy and might enhance the anti-Parkinsonian effects of L-DOPA, though at the expense of worsening dyskinesia.

Effects of Schedule I drug laws on neuroscience research and treatment innovation

Many psychoactive drugs are used recreationally, particularly by young people. This use and its perceived dangers have led to many different classes of drugs being banned under national laws and international conventions. Indeed, the possession of cannabis, 3,4-methylenedioxy-N-methylamphetamine (MDMA; also known as ecstasy) and psychedelics is stringently regulated. An important and unfortunate outcome of the controls placed on these and other psychoactive drugs is that they make research into their mechanisms of action and potential therapeutic uses - for example, in depression and post-traumatic stress disorder - difficult and in many cases almost impossible.

Effects of a short-course MDMA binge on dopamine transporter binding and on levels of dopamine and its metabolites in adult male rats

Although the recreational drug 3,4-methylenedioxymethamphetamine (MDMA) is often described as a selective serotonergic neurotoxin, some research has challenged this view. The objective of this study was to determine the influence of MDMA on subsequent levels of two different markers of dopaminergic function, the dopamine transporter (DAT) as well as dopamine and its major metabolites. In experiment I, adult male Sprague-Dawley rats were administered either a low or moderate dose MDMA binge (2.5 or 5.0mg/kg×4 with an inter-dose interval of 1h) or saline, and were killed 1 week later. The moderate dose dramatically reduced [(3)H]WIN 35,428 binding to striatal DAT by 73.7% (P≤0.001). In experiment II, animals were binged with a higher dose of MDMA (10mg/kg×4) to determine the drug's effects on concentrations of serotonin (5-HT), dopamine, and their respective major metabolites 5-hydroxyindoleacetic acid (5-HIAA), dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in the striatum and frontal cortex 1 week later. As expected, MDMA significantly reduced 5-HT and 5-HIAA (≥50%) in these structures, while only a marginal decrease in dopamine was noted in the striatum. In contrast, levels of DOPAC (34.3%, P<0.01) and HVA (33.5%, P<0.001) were reduced by MDMA treatment, suggesting a decrease in dopamine turnover. Overall, these findings indicate that while serotonergic markers are particularly vulnerable to MDMA-induced depletion, significant dopaminergic deficits may also occur under some conditions. Importantly, DAT expression may be more vulnerable to perturbation by MDMA than dopamine itself.

[Communication of scientific fraud]

There is for a scientific journal several levels of communication depending of the degree of suspicion or certainty of a case of error or fraud. The task is increasingly difficult for journal editors as disclosed cases of fraud are more common and scientific communication on this topic is growing. Biomedical fraud is fairly little reported by the mainstream press and causes of this low interest are not currently well understood. The difficulty of processing this type of news for journalists appears to be one possible reason. The potentially numerous and significant consequences of fraud on health professionals are poorly documented. Though it is likely to cause a feeling of distrust and create controversy, the impact of fraud on the general public is poorly studied and appears multifactorial.

The A2a adenosine receptor modulates the reinforcement efficacy and neurotoxicity of MDMA

Adenosine is an endogenous purine nucleoside that plays a neuromodulatory role in the central nervous system. A2a adenosine receptors have been involved in reward-related processes, inflammatory phenomena and neurotoxicity reactions. In the present study, we investigated the role of A2a adenosine receptors on the acute pharmacological effects, reinforcement and neuroinflammation induced by MDMA administration. First, the acute effects of MDMA on body temperature, locomotor activity and anxiety-like responses were measured in A2a knockout mice and wild-type littermates. Second, MDMA reinforcing properties were evaluated using the intravenous self-administration paradigm. Finally, we assessed striatal astrogliosis and microgliosis as markers of MDMA neurotoxicity. Our results showed that acute MDMA produced a biphasic effect on body temperature and increased locomotor activity and anxiogenic-like responses in both genotypes. However, MDMA reinforcing properties were dramatically affected by the lack of A2a adenosine receptors. Thus, wild-type mice maintained MDMA self-administration under a fixed ratio 1 reinforcement schedule, whereas the operant response appeared completely abolished in A2a knockout mice. In addition, the MDMA neurotoxic regime produced an enhanced inflammatory response in striatum of wild-type mice, revealed by a significant increase in glial expression, whereas such activation was attenuated in mutant mice. This is the first report indicating that A2a adenosine receptors play a key role in reinforcement and neuroinflammation induced by the widely used psychostimulant.

Manganese-Induced Parkinsonism due to Ephedrone Abuse

During recent years, a syndrome of hypokinesia, dysarthria, dystonia, and postural impairment, related to intravenous use of a "designer" psychostimulant derived from pseudoephedrine using potassium permanganate as the oxidant, has been observed in drug addicts in several countries in Eastern Europe with some cases also in Western countries. A levodopa unresponsive Parkinsonian syndrome occurs within a few months of abusing the homemade drug mixture containing ephedrone (methcathinone) and manganese. The development of this neurological syndrome has been attributed to toxic effects of manganese, but the role of the psychostimulant ephedrone is unclear. This paper describes the clinical syndrome, results of neuroimaging, and therapeutic attempts.

The impact of positive and negative ecstasy-related information on ecstasy use among college students: Results of a longitudinal study

AIMS: To: 1) estimate the proportion of students exposed to specific types of information regarding the positive and negative effects of ecstasy, 2) test models that quantified the relationship between exposure to these messages and subsequent ecstasy use, controlling for peer drug use and sensation-seeking. METHODS: As part of the College Life Study, 447 students, ages 17-20, from a university in the mid-Atlantic region of the US completed an in person interview plus three follow-up assessments. FINDINGS: Individuals who had heard a greater number of negative messages were significantly more likely to use ecstasy, even controlling for positive messages, prior ecstasy use, peer ecstasy use, perceived harm, sensation-seeking, sex, and race. Some messages were significant at the bivariate level. CONCLUSIONS: Ecstasy use may have been influenced more by the content of the messages than by the quantity or diversity of messages. Interventions should be designed to address both positive and negative perceptions about a particular drug, rather than focusing exclusively on the negative information. Future evaluations should focus on the effectiveness of multi-pronged sustainable prevention programs in reducing adolescent drug use risk.

Recreational ecstasy use and the neurotoxic potential of MDMA: current status of the controversy and methodological issues

The controversy over possible MDMA-induced serotonergic neurotoxicity in human recreational ecstasy users is examined critically in light of recent research findings. Although the designs of such studies have improved considerably since the 1990s, the evidence to date remains equivocal for a number of reasons, including (1) inconsistent findings on the existence and reversibility of persistent ecstasy-related serotonergic and cognitive deficits; (2) lack of clear association between changes in brain imaging measures and functional deficits attributed to MDMA-induced neurotoxicity; (3) the contribution of concomitant cannabis or other drug use to both brain imaging abnormalities and cognitive deficits; (4) methodological shortcomings such as failure to adequately match samples of ecstasy users and controls; (5) the questionable relevance of animal models of MDMA-induced neurotoxicity to typical human patterns of ecstasy use; and (6) the potential role of inherent pre-drug deficits in serotonergic systems, impulse control and executive cognitive function that may predispose to excessive use of drugs including ecstasy. Given the retrospective nature of nearly all studies of ecstasy users to date, the controversy over whether MDMA has ever caused neurotoxicity or cognitive deficit in human ecstasy users is likely to continue for some time without resolution.

Baboon carboxylesterases 1 and 2: sequences, structures and phylogenetic relationships with human and other primate carboxylesterases

BACKGROUND

Carboxylesterase (CES) is predominantly responsible for the detoxification of a wide range of drugs and narcotics, and catalyze several reactions in cholesterol and fatty acid metabolism. Studies of the genetic and biochemical properties of primate CES may contribute to an improved understanding of human disease, including atherosclerosis, obesity and drug addiction, for which non-human primates serve as useful animal models.

METHODS

We cloned and sequenced baboon CES1 and CES2 and used in vitro and in silico methods to predict protein secondary and tertiary structures, and examined evolutionary relationships for these enzymes with other primate and mouse CES orthologs.

RESULTS AND CONCLUSIONS

We found that baboon CES1 and CES2 proteins retained extensive similarity with human CES1 and CES2, shared key structural features reported for human CES1, and showed family specific sequences consistent with their multimeric and monomeric subunit structures respectively.

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.

Brain serotonin transporter in human methamphetamine users

RATIONALE

Research on methamphetamine (MA) toxicity primarily focuses on the possibility that some of the behavioural problems in human MA users might be caused by damage to brain dopamine neurones. However, animal data also indicate that MA can damage brain serotonin neurones, and it has been suggested that cognitive problems and aggression in MA users might be explained by serotonergic damage. As information on the brain serotonin system in human MA users is fragmentary, our objective was to determine whether protein levels of serotonin transporter (SERT), a key marker of serotonin neurones, are decreased in brain of chronic MA users.

METHODS

SERT immunoreactivity was measured using an immunoblotting procedure in autopsied brain of 16 chronic MA users testing positive for the drug in blood and brain and matched controls.

RESULTS

SERT levels were non-significantly decreased (-14% to -33%) in caudate, putamen and thalamus (normal in hippocampus), and, unlike the robust striatal dopamine reduction, there was marked overlap between control and MA user ranges. Concentrations of SERT were significantly decreased (-23% to -39%) in orbitofrontal and occipital cortices (normal in frontopolar and temporal cortices).

CONCLUSIONS

Our data suggest that MA might modestly damage brain serotonin neurones and/or inhibit SERT protein expression, with cerebral cortex being more affected than sub-cortical regions. The SERT reduction in orbitofrontal cortex complements other data suggesting involvement of this area in MA-related behaviour. Decreased brain SERT could also be related to the clinical finding that treatment with a selective serotonin re-uptake inhibitor might increase relapse to MA.

Escalating dose-multiple binge methamphetamine exposure results in degeneration of the neocortex and limbic system in the rat

Abuse of stimulant drugs such as methamphetamine (METH) and cocaine has been associated with long-lasting persistent behavioral alterations. Although METH-induced changes in the striatal dopaminergic system might play a role in these effects, the potential underlying neuroanatomical substrate for the chronic cognitive dysfunction in METH users is unclear. To investigate the involvement of non-dopaminergic systems in the neurotoxic effects of METH, we treated rats with an escalating dose-multiple binge regimen, which we have suggested may more closely simulate human METH exposure profiles. Combined neuropathological and stereological analyses showed that 30 days after the last binge, there was shrinkage and degeneration in the pyramidal cell layers of the frontal cortex and in the hippocampal CA3 region. Further immunocytochemical analysis showed that METH exposure resulted in loss of calbindin interneurons in the neocortex and selective damage to pyramidal neurons in the CA3 region of the hippocampus and granular cells in the dentate gyrus that was accompanied by microglial activation. Taken together, these studies suggest that selective degeneration of pyramidal neurons and interneurons in the neocortex and limbic system might be involved in the cognitive alterations in METH users.

Oral administration of (+/-)3,4-methylenedioxymethamphetamine and (+)methamphetamine alters temperature and activity in rhesus macaques

RATIONALE

Emergency Department visits and fatalities in which (+/-)3,4-methylenedioxymethamphetamine (MDMA) or (+)methamphetamine (METH) are involved frequently feature unregulated hyperthermia. MDMA and METH significantly elevate body temperature in multiple laboratory species and, most importantly, can also produce unregulated and threatening hyperthermia in nonhuman primates. A majority of prior animal studies have administered drugs by injection whereas human consumption of "Ecstasy" is typically oral, an important difference in route of administration which may complicate the translation of animal data to the human condition.

OBJECTIVE

To determine if MDMA and METH produce hyperthermia in monkeys following oral administration as they do when administered intramuscularly.

METHODS

Adult male rhesus monkeys were challenged intramuscularly (i.m.) and per os (p.o.) with 1.78 or 5 mg/kg (+/-)MDMA and with 0.1 or 0.32 mg/kg (+)METH. Temperature and activity were monitored with a radiotelemetry system.

RESULTS

Oral administration of either MDMA or METH produced significant increases in body temperature. Locomotor activity was suppressed by MDMA and increased by METH following either route of administration.

CONCLUSIONS

The data show that the oral route of administration is not likely to qualitatively reduce the temperature increase associated with MDMA or METH although oral administration did slow the rate of temperature increase. It is further established that MDMA reduces activity in monkeys even after relatively high doses and oral administration.

Apparent Transient Effects of Recent ???Ecstasy??? Use on Cognitive Performance and Extrapyramidal Signs in Human Subjects

OBJECTIVES

Our purpose is to investigate cognitive performance and extrapyramidal function early after ecstasy use.

BACKGROUND

Ecstasy, containing 3,4 methylenedioxymethamphetamine, has shown evidence of causing cognitive deficits and parkinsonian signs. Previous research has examined cognitive performance after a period of prolonged abstinence, but research assessing the early effects of ecstasy after recent use is limited despite temporal neurochemical differences demonstrated in nonhuman models.

METHODS

This study compared task performance between 13 ecstasy users (10 to 15 h postdrug use) and a control group on a battery of neuropsychologic assessments while matching for education level, sleep deprivation, and premorbid IQ. The groups were also compared on measures relating to parkinsonian signs.

RESULTS

The ecstasy subjects showed impairments on measures of executive function as evaluated by Raven's Standard Progressive Matrices (SPM) and the Wisconsin Card Sorting Task (WCST). Short-delay free recall memory was also impaired in ecstasy subjects on the California Verbal Learning Test (CVLT-II). No extrapyramidal motor impairments were detected.

CONCLUSIONS

These deficits resemble deficits previously reported in chronic ecstasy use but also seem to reveal transient impairments in executive function. Future research is needed to better understand the neurologic and neuropsychologic implications of ecstasy use across time and extent of use.

Effects of (+/-)3,4-methylenedioxymethamphetamine, (+/-)3,4-methylenedioxyamphetamine and methamphetamine on temperature and activity in rhesus macaques

Severe and malignant hyperthermia is a frequently reported factor in emergency department (ED) visits and fatalities in which use of amphetamine drugs, such as (+/-)3,4-methylenedioxymethamphetamine (MDMA), (+/-)3,4-methylenedioxyamphetamine (MDA) and (+)methamphetamine (METH), is confirmed. Individuals who use "ecstasy" are also often exposed, intentionally or otherwise, to several of these structurally-related compounds alone or in combination. In animal studies the degree of (subcritical) hyperthermia is often related to the severity of amphetamine-induced neurotoxicity, suggesting health risks to the human user even when emergency medical services are not invoked. A clear distinction of thermoregulatory risks posed by different amphetamines is therefore critical to understand factors that may produce medical emergency related to hyperthermia. The objective of this study was therefore to determine the relative thermoregulatory disruption produced by recreational doses of MDMA, MDA and METH in nonhuman primates. Body temperature and spontaneous home cage activity were monitored continuously in six male rhesus monkeys via radiotelemetric devices. The subjects were challenged intramuscularly with 0.56-2.4 mg/kg MDMA, 0.56-2.4 mg/kg MDA and 0.1-1.0 mg/kg METH. All three amphetamines significantly elevated temperature; however the time course of effects differed. The acute effect of METH lasted hours longer than MDA or MDMA and a disruption of nighttime circadian cooling was observed as long as 18 h after 1.0 mg/kg METH and 1.78-2.4 mg/kg MDA, but not after MDMA. Activity levels were only reliably increased by 0.32 mg/kg METH. It is concluded that while all three substituted amphetamines produce hyperthermia in rhesus monkeys, the effects do not depend on elevated locomotor activity and exhibit differences between compounds. The results highlight physiological risks posed both by recreational use of the amphetamines and by current trials for clinical MDMA use.

Association of paradoxical sleep deprivation and ecstasy (MDMA) enhances genital reflexes in male rats

Ecstasy ((+/-)3,4-methylenedioxymethamphetamine, MDMA) is a psychostimulant and a synthetic derivative of amphetamine that, according to its consumers, promotes the enhancement of sexual pleasure. This study sought to investigate the effects of ecstasy in the genital reflexes of paradoxical sleep deprived (PSD) male rats. Distinct groups of PSD rats were administered with saline or different doses of ecstasy. The incidence of genital reflexes was verified for 100 min. The four doses that were used induced genital reflexes in PSD animals and these significantly differed from their respective treated control groups. Under the influence of two intermediary doses (2.5 and 5mg/kg), all animals displayed erection and ejaculation. The frequency of genital reflexes was also significantly greater than in relation to the PSD-saline group. The comparison between cocaine and ecstasy in PSD rats revealed that ecstasy induced more erections and ejaculations than cocaine. Thus, the present results showed a great enhancement of the genital reflexes of PSD rats that might have occurred due to serotoninergic alterations induced by this illicit substance when associated to sleep deprivation.

Neuroimaging findings with MDMA/ecstasy: technical aspects, conceptual issues and future prospects

Users of ecstasy (3,4-methylenedioxymethamphetamine; MDMA) may be at risk of developing MDMA-induced injury to the serotonin (5-HT) system. Previously, there were no methods available for directly evaluating the neurotoxic effects of MDMA in the living human brain. However, development of in vivoneuroimaging tools have begun to provide insights into the effects of ecstasy on the human brain. Single photon emission computed tomography (SPECT), positron emission computed tomography (PET) and proton magnetic resonance spectroscopy (1H-MRS) studies which have evaluated ecstasy's neurotoxic potential will be reviewed and discussed in terms of technical aspects, conceptual issues and future prospects. Although PET and SPECT may be limited by several factors such as the low cortical uptake and the use of a non-optimal reference region (cerebellum) the few studies conducted so far provide suggestive evidence that people who heavily use ecstasy are at risk of developing subcortical, and probably also cortical reductions in serotonin transporter (SERT) densities, a marker of 5-HT neurotoxicity. There seem to be dose-dependent and transient reductions in SERT for which females may be more vulnerable than males. 1H-MRS appears to be a less sensitive technique for studying ecstasy's neurotoxic potential. Whether individuals with a relatively low ecstasy exposure also demonstrate loss of SERT needs to be determined. Because most studies have had a retrospective design, in which evidence is indirect and differs in the degree to which any causal links can be implied, longitudinal studies in human ecstasy users are needed to draw definite conclusions.

Selective impairment of sadness and disgust recognition in abstinent ecstasy users

Previous data have suggested that ecstasy use may affect cognitive functions. The relationship between ecstasy use and emotion recognition remains largely unknown. This study reports the findings on the neuropsychological effects of ecstasy use on recognition of basic human emotions among 100 abstinent ecstasy users, along with 100 demographically matched nonusers. Recognition of both facial and prosodic emotions was studied. In addition, neuropsychological predictors of emotion recognition for abstinent ecstasy users were examined. The results showed that abstinent ecstasy users were impaired, relative to nonusers, on overall emotion recognition. In particular, recognition of sadness and disgust was significantly affected. The emotion-recognition deficits observed among the abstinent ecstasy users may reflect a complex derangement of monoamines and/or general degenerative change observed in the addicted populations. The length of time in months since ecstasy was last consumed, cumulative ecstasy dosage, and years of education negatively predicted various domains of emotion recognition. The observation that nonverbal and verbal fluency functions were significant predictors of emotion identification, as well as of recognition of sadness and disgust, suggests that the frontal executive system might be affected by ecstasy use.

Methamphetamine stimulates interferon inducible genes in HIV infected brain

OBJECTIVE

To study the synergism of HIV and methamphetamine.

DESIGN AND METHODS

We undertook a microarray study using RNA from the frontal cortex of 15 individuals with HIV infection to initially identify genes that are differentially regulated by HIV encephalitis (HIVE). From the analysis of the microarray data, we identified candidate genes to be validated by quantitative real time PCR (qRT-PCR) and to assess if these genes were differentially modulated in individuals with HIVE and documented methamphetamine use.

RESULTS

Analysis of microarray data revealed that genes involved in several categories were dysregulated in HIVE. We then chose 15 candidate genes for validation by qRT-PCR and analyzed the tissue concentration of these genes across three groups: those with HIV infection and no brain pathology, those with HIVE, and those with both HIVE and a history of methamphetamine use. We noted that there was upregulation of interferon inducible genes in the HIVE with methamphetamine using group, which together as a gene group was highly statistically significant (p=0.0064).

CONCLUSION

These findings indicate that dysregulation of interferon inducible genes may underlie the pathogenic mechanism resulting in greater neurodegenerative and neurocognitive burden that occurs in methamphetamine using HIV infected individuals.

MDMA alters the response of the mammalian circadian clock in hamsters: effects on re-entrainment and triazolam-induced phase shifts

Serotonin (5-hydroxytryptamine or 5-HT) is a neurotransmitter that is involved in a wide range of behavioural and physiological processes. Previous work has indicated that serotonin is important in the regulation of the circadian clock, which is located in the suprachiasmatic nuclei (SCN) of the hypothalamus. 3,4-methylenedioxymethamphetamine (MDMA or 'Ecstasy'), which is widely used as a recreational drug of abuse, is a serotonin neurotoxin in animals and non-human primates. Previous work has shown that MDMA exposure can alter circadian clock function both in vitro and in vivo. Evidence shows that 5-HT may have a modulatory role in the regulation of the circadian clock by non-photic stimuli, such as the benzodiazepine triazolam (TRZ). Triazolam is a short-acting benzodiazepine that results in phase advances of the wheel running activity in hamsters when administered during the mid-subjective day. In the present study, male Syrian hamsters treated with TRZ (5 mg/kg) at ZT6 significantly phase advanced their clock. Treatment with MDMA significantly diminished the TRZ induced phase shift in hamsters. Previous evidence shows the involvement of 5-HT in the re-synchronisation of the endogenous clock to a new shifted light-dark cycle. Untreated animals were successfully entrained to a new, 6 h advanced light-dark cycle within an average of 4.5 +/- 0.1 days. Following treatment with MDMA, these animals took an average of 8.3 +/- 0.1 days to re-entrain to a shifted environmental cycle. Immunohistochemical analysis revealed that animals treated with MDMA showed reduced serotonin staining, as evidenced by a decrease in innervation density in the SCN. No significant differences were found in cell counts within the raphe nuclei. These results demonstrate the importance of the serotonergic system in the modulation of photic and non-photic responses of the circadian pacemaker.

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.

Is ecstasy perceived to be safe? A critical survey

Recent publications claim that the recreational drug ecstasy is considered to be safe by many or most ecstasy users, or by young people or the general public. Unfortunately, there are no references that provide any support for this claim. Previous studies of various populations, including drug users and adolescents in several nations, also failed to support claims of the perceived safety of ecstasy. Epidemiological surveys from the USA and UK consistently report high proportions of young people who perceive great risk in using ecstasy. Studies in ecstasy users show that they are aware of a number of short- and long-term risks of ecstasy use, although, in the absence of actual problems, they evaluate the personal significance of these risks as low. This study further investigated the perceived harmfulness of ecstasy, drawing on an online survey of over 900 drug users. Little support for the claim was found. Seventy-three percent of the participants in the online survey viewed ecstasy as carrying at least 'some risk'. The claim of ecstasy's perceived safety is plausibly based on researchers' assumptions that the continued widespread use of the drug indicates that users are unaware of the associated risks, and that informing them about these risks would lead to a reduction in drug use. We argue that these assumptions are inadequate and that drug information and harm reduction strategies should focus on more affective and personally significant aspects of risk perception.

Modeling human methamphetamine exposure in nonhuman primates: chronic dosing in the rhesus macaque leads to behavioral and physiological abnormalities

Acute high dose methamphetamine (METH) dosing regimens are frequently used in animal studies, however, these regimens can lead to considerable toxicity and even death in experimental animals. Acute high dosing regimens are quite distinct from the chronic usage patterns found in many human METH abusers. Furthermore, such doses, especially in nonhuman primates, can result in unexpected death, which is unacceptable, especially when such deaths fail to accurately model effects of human usage. As a model of chronic human METH abuse we have developed a nonlethal chronic METH administration procedure for the rhesus macaque that utilizes an escalating dose protocol. This protocol slowly increases the METH dosage from 0.1 to 0.7 mg/kg b.i.d. over a period of 4 weeks, followed by a period of chronic METH administration at 0.75 mg/kg b.i.d. (= total daily METH administration of 1.5 mg/kg). In parallel to human usage patterns, METH injections were given 20-23 times a month. This regimen produced a number of behavioral and physiological effects including decreased food intake and a significant increase in urinary cortisol excretion.