1
|
Roberts CA, Jones A, Montgomery C. Meta-analysis of molecular imaging of serotonin transporters in ecstasy/polydrug users. Neurosci Biobehav Rev 2016; 63:158-67. [DOI: 10.1016/j.neubiorev.2016.02.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 01/11/2016] [Accepted: 02/02/2016] [Indexed: 10/22/2022]
|
2
|
McCann UD, Szabo Z, Vranesic M, Palermo M, Mathews WB, Ravert HT, Dannals RF, Ricaurte GA. Positron emission tomographic studies of brain dopamine and serotonin transporters in abstinent (+/-)3,4-methylenedioxymethamphetamine ("ecstasy") users: relationship to cognitive performance. Psychopharmacology (Berl) 2008; 200:439-50. [PMID: 18661256 PMCID: PMC2789420 DOI: 10.1007/s00213-008-1218-4] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Accepted: 05/28/2008] [Indexed: 11/29/2022]
Abstract
BACKGROUND (+/-)3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") is a recreational drug and brain serotonin (5-HT) neurotoxin. Under certain conditions, MDMA can also damage brain dopamine (DA) neurons, at least in rodents. Human MDMA users have been found to have reduced brain 5-HT transporter (SERT) density and cognitive deficits, although it is not known whether these are related. This study sought to determine whether MDMA users who take closely spaced sequential doses, which engender high plasma MDMA concentrations, develop DA transporter (DAT) deficits, in addition to SERT deficits, and whether there is a relationship between transporter binding and cognitive performance. MATERIALS AND METHODS Sixteen abstinent MDMA users with a history of using sequential MDMA doses (two or more doses over a 3- to 12-h period) and 16 age-, gender-, and education-matched controls participated. Subjects underwent positron emission tomography with the DAT and SERT radioligands, [11C]WIN 35,428 and [11C]DASB, respectively. Subjects also underwent formal neuropsychiatric testing. RESULTS MDMA users had reductions in SERT binding in multiple brain regions but no reductions in striatal DAT binding. Memory performance in the aggregate subject population was correlated with SERT binding in the dorsolateral prefrontal cortex, orbitofrontal cortex, and parietal cortex, brain regions implicated in memory function. Prior exposure to MDMA significantly diminished the strength of this relationship. CONCLUSIONS Use of sequential MDMA doses is associated with lasting decreases in brain SERT, but not DAT. Memory performance is associated with SERT binding in brain regions involved in memory function. Prior MDMA exposure appears to disrupt this relationship. These data are the first to directly relate memory performance to brain SERT density.
Collapse
Affiliation(s)
- Una D. McCann
- Department of Psychiatry, The Johns Hopkins School of Medicine, Baltimore, MD, USA,Department of Psychiatry and Behavioral Sciences, 5510 Nathan Shock Drive, Baltimore, MD 21224, Phone: 410-550-2596; E-mail: ; FAX 410-550-2005
| | - Zsolt Szabo
- Department of Radiology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Melin Vranesic
- Department of Radiology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Michael Palermo
- Department of Neurology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - William B. Mathews
- Department of Radiology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Hayden T. Ravert
- Department of Radiology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Robert F. Dannals
- Department of Radiology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - George A. Ricaurte
- Department of Neurology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| |
Collapse
|
3
|
Martinez D, Kim JH, Krystal J, Abi-Dargham A. Imaging the neurochemistry of alcohol and substance abuse. Neuroimaging Clin N Am 2008; 17:539-55, x. [PMID: 17983969 DOI: 10.1016/j.nic.2007.07.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Animal models of abuse and dependence have long suggested that chronic drug and alcohol exposure is associated with marked changes in neurochemistry. The development of PET and SPECT imaging now allows investigation of the effects of addiction on the neurochemistry of the human brain. This article reviews the literature of radiochemical imaging in cocaine, alcohol, heroin, methamphetamine, MDMA, and ketamine abuse and dependence.
Collapse
Affiliation(s)
- Diana Martinez
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, 1051 Riverside Drive, Box #31, New York, NY 10032, USA.
| | | | | | | |
Collapse
|
4
|
Reneman L, de Win MML, van den Brink W, Booij J, den Heeten GJ. Neuroimaging findings with MDMA/ecstasy: technical aspects, conceptual issues and future prospects. J Psychopharmacol 2006; 20:164-75. [PMID: 16510475 DOI: 10.1177/0269881106061515] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
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.
Collapse
Affiliation(s)
- Liesbeth Reneman
- Graduate School of Neurosciences, Department of Radiology, Academic Medical Centre, University of Amsterdam, The Netherlands.
| | | | | | | | | |
Collapse
|
5
|
de Win MML, Habraken JBA, Reneman L, van den Brink W, den Heeten GJ, Booij J. Validation of [(123)I]beta-CIT SPECT to assess serotonin transporters in vivo in humans: a double-blind, placebo-controlled, crossover study with the selective serotonin reuptake inhibitor citalopram. Neuropsychopharmacology 2005; 30:996-1005. [PMID: 15770240 DOI: 10.1038/sj.npp.1300683] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Disturbances in the serotonin (5-HT) system are associated with various neuropsychiatric disorders. The 5-HT system can be studied in vivo by measuring 5-HT transporter (SERT) densities using (123)iodine-labeled 2beta-carbomethoxy-3beta(4-iodophenyl)tropane ([(123)I]beta-CIT) and single photon emission computed tomography (SPECT). Validation of this technique is important because [(123)I]beta-CIT does not bind selectively to SERTs. Some studies have validated this technique in vivo in the human brain in SERT-rich areas, but the technique has not been validated yet in SERT-low cortical areas. The aim of this study was to further validate [(123)I]beta-CIT SPECT in assessing SERTs in vivo in humans in both SERT-rich and SERT-low areas. A double-blind, placebo-controlled, crossover design was used with the selective 5-HT reuptake inhibitor (SSRI) citalopram. Six male subjects underwent two [(123)I]beta-CIT SPECT sessions: one after pretreatment with citalopram and one after placebo. Scans were acquired 4 h and 22-27 h p.i., and both region-of-interest and voxel-by-voxel analyses were performed. Citalopram reduced [(123)I]beta-CIT binding ratios in SERT-rich midbrain and (hypo)thalamus. Binding ratios were also lower after citalopram in SERT-low cortical areas, but statistical significance was only reached in several cortical areas using voxel-by-voxel analysis. In addition, citalopram increased binding ratios in the DAT-rich striatum and increased absolute uptake in the cerebellum. The results show that [(123)I]beta-CIT SPECT is a valid technique to study SERT binding in vivo in human brain in SERT-rich areas. Although we provide some evidence that [(123)I]beta-CIT SPECT may be used to measure SERTs in SERT-low cortical areas, these measurements must be interpreted with caution.
Collapse
Affiliation(s)
- Maartje M L de Win
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | | | |
Collapse
|
6
|
Frankle WG, Slifstein M, Talbot PS, Laruelle M. Neuroreceptor Imaging in Psychiatry: Theory and Applications. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2005; 67:385-440. [PMID: 16291028 DOI: 10.1016/s0074-7742(05)67011-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- W Gordon Frankle
- Departments of Psychiatry, Columbia University College of Physicians and Surgeons and New York State Psychiatric Institute, New York, New York 10032, USA
| | | | | | | |
Collapse
|
7
|
Cole JC, Sumnall HR. The pre-clinical behavioural pharmacology of 3,4-methylenedioxymethamphetamine (MDMA). Neurosci Biobehav Rev 2003; 27:199-217. [PMID: 12788333 DOI: 10.1016/s0149-7634(03)00031-9] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
3,4-Methylenedioxymethamphetamine (MDMA) is a relatively novel drug of abuse and as such little is currently known of its behavioural pharmacology. This review aims to examine whether MDMA represents a novel class of abused drug. MDMA is known as a selective serotonergic neurotoxin in a variety of animal species but acutely it is a potent releaser and/or reuptake inhibitor of presynaptic serotonin, dopamine, noradrenaline, and acetylcholine. Interaction of these effects contributes to its behavioural pharmacology, in particular its effects on body temperature. Drug discrimination studies indicate that MDMA and related drugs produce unique interoceptive effects which have led to their classification as entactogens. This is supported by results from other behavioural paradigms although there is evidence for dose dependency of MDMA-specific effects. MDMA also produces conditioned place preference but is not a potent reinforcer in self-administration studies. These unique behavioural effects probably underlie its current popularity. MDMA is found in the street drug ecstasy but it may not be appropriate to equate the two as other drugs are routinely found in ecstasy tablets
Collapse
Affiliation(s)
- Jon C Cole
- Department of Psychology, University of Liverpool, L69 7ZA, Liverpool, UK.
| | | |
Collapse
|
8
|
Lyles J, Cadet JL. Methylenedioxymethamphetamine (MDMA, Ecstasy) neurotoxicity: cellular and molecular mechanisms. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 2003; 42:155-68. [PMID: 12738056 DOI: 10.1016/s0165-0173(03)00173-5] [Citation(s) in RCA: 148] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methylenedioxymethamphetamine (MDMA, Ecstasy) is a very popular drug of abuse. This has led to new intense concerns relevant to its nefarious neuropsychiatric effects. These adverse events might be related to the neurotoxic effects of the drug. Although the mechanisms of MDMA-induced neurotoxicity remain to be fully characterized, exposure to the drug can cause acute and long-term neurotoxic effects in animals and nonhuman primates. Recent studies have also documented possible toxic effects in the developing fetus. Nevertheless, there is still much debate concerning the effects of the drug in humans and how to best extrapolate animal and nonhuman primate data to the human condition. Herein, we review the evidence documenting the adverse effects of the drug in some animal models. We also discuss possible mechanisms for the development of MDMA neurotoxicity. Data supporting deleterious effects of this drug on the developing fetus are also described. Much remains to be done in order to clarify the molecular and biochemical pathways involved in the long-term neuroplastic changes associated with MDMA abuse.
Collapse
Affiliation(s)
- Johnalyn Lyles
- Molecular Neuropsychiatry Branch, National Institutes of Health/National Institute on Drug Abuse Intramural Research Program, 5500 Nathan Shock Drive, Baltimore, MD 21224, USA
| | | |
Collapse
|
9
|
Abstract
Ecstasy is the second most widely abused illegal drug in Europe. Ecstasy is the colloquial name for 3,4-methylenedioxymethamphetamine (MDMA), but not all Ecstasy tablets contain MDMA. When taken in hot, crowded environments, Ecstasy/MDMA users have developed acute complications that have had fatal consequences. Epidemiological evidence indicates that adverse reactions to Ecstasy/MDMA intoxication are rare and idiosyncratic. Potential mechanisms of action are reviewed. In animal studies, MDMA damages serotonergic fibres and reduces the number of serotonin transporter sites within the CNS. Demonstration of neurotoxicity in human users of Ecstasy is hampered by a number of confounds that the majority of published studies have failed to address. These confounds are reviewed and their impact is discussed.
Collapse
Affiliation(s)
- J C Cole
- Psychology Department, Liverpool University, Liverpool L69 7ZA, UK.
| | | |
Collapse
|
10
|
Abstract
Understanding the diverse functions of serotonin in the human brain can be obtained through examination of subjects having a lower than normal number of brain serotonin neurons. Behavioral abnormalities consistent with brain serotonergic damage have been reported in some polydrug users who also use the neurotoxin ecstasy (methylenedioxymethamphetamine, MDMA). This review evaluates the evidence from neuroimaging studies that brain serotonergic damage is a feature of human users of ecstasy. To date, neuroimaging studies designed to establish whether levels of brain serotonin neurons are lower than normal in ecstasy users have employed radioligands that bind to one component of the serotonin neuron, the serotonin transporter (SERT). Because these studies are methodologically flawed in terms of reliability or validity of the SERT measurement and appear to have employed polydrug users, no definitive information is yet available on the question of ecstasy toxicity to human brain serotonin neurons. Until these issues are resolved, it cannot be assumed that ecstasy exposure represents a chronic serotonin deficiency condition.
Collapse
Affiliation(s)
- Stephen J Kish
- Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, 250 College Street, M5T 1R8, Toronto, Ontario, Canada.
| |
Collapse
|
11
|
Abstract
Increasing use of 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy") has been accompanied by concern about acute and possible long-term toxicity. This article discusses acute serious toxicity, chronic toxicity, and common problems associated with Ecstasy use, as well as the implications of these areas for prevention programs targeted at current Ecstasy users. The low incidence of serious adverse events in users creates difficulties for attempts to develop harm reduction recommendations. Many hypothesized risk factors for serious adverse events cannot be confirmed or denied and may not be associated with dramatic elevations in risk. Research on chronic toxicity in users provides strong evidence of neurophysiological changes and suggestive evidence of possible neurocognitive changes. Because these worrisome changes are clinically subtle, users may not be influenced by concerns of neurotoxicity. In contrast, common Ecstasy-related complaints are relatively well documented and have identified risk factors, including factors relating to extent of Ecstasy use (such as "binges"). Common complaints include modest acute and subacute adverse effects,some lasting several days, and problems in life. The apparent willingness of users to modify drug use and other behaviors to decrease these common problems could be used by harm reduction or other prevention programs to encourage users to decrease the extent of Ecstasy use.
Collapse
|
12
|
Affiliation(s)
- G A Ricaurte
- Department of Neurology Psychiatry, Johns Hopkins University School of Medicine, 21224, Baltimore, MD, USA.
| | | |
Collapse
|