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result(s) for
"N-Methyl-3,4-methylenedioxyamphetamine - toxicity"
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Inhibition of serotonin transporters disrupts the enhancement of fear memory extinction by 3,4-methylenedioxymethamphetamine (MDMA)
by
Norrholm, Seth D.
,
Dunlop, Boadie W.
,
Jovanovic, Tanja
in
Animals
,
Biomedical and Life Sciences
,
Biomedicine
2017
Rationale
3,4-Methylenedioxymethamphetamine (MDMA) persistently improves symptoms of post-traumatic stress disorder (PTSD) when combined with psychotherapy. Studies in rodents suggest that these effects can be attributed to enhancement of fear memory extinction. Therefore, MDMA may improve the effects of exposure-based therapy for PTSD, particularly in treatment-resistant patients. However, given MDMA’s broad pharmacological profile, further investigation is warranted before moving to a complex clinical population.
Objectives
We aimed to inform clinical research by providing a translational model of MDMA’s effect, and elucidating monoaminergic mechanisms through which MDMA enhances fear extinction.
Methods
We explored the importance of monoamine transporters targeted by MDMA to fear memory extinction, as measured by reductions in conditioned freezing and fear-potentiated startle (FPS) in mice. Mice were treated with selective inhibitors of individual monoamine transporters prior to combined MDMA treatment and fear extinction training.
Results
MDMA enhanced the lasting extinction of FPS. Acute and chronic treatment with a 5-HT transporter (5-HTT) inhibitor blocked MDMA’s effect on fear memory extinction. Acute inhibition of dopamine (DA) and norepinephrine (NE) transporters had no effect. 5-HT release alone did not enhance extinction. Blockade of MDMA’s effect by 5-HTT inhibition also downregulated 5-HT
2A
-mediated behavior, and 5-HT
2A
antagonism disrupted MDMA’s effect on extinction.
Conclusions
We validate enhancement of fear memory extinction by MDMA in a translational behavioral model, and reveal the importance of 5-HTT and 5-HT
2A
receptors to this effect. These observations support future clinical research of MDMA as an adjunct to exposure therapy, and provide important pharmacological considerations for clinical use in a population frequently treated with 5-HTT inhibitors.
Journal Article
Toxicity of the 3,4-methylenedioxymethamphetamine and its enantiomers to Daphnia magna after isolation by semipreparative chromatography
by
Tiritan, Maria Elizabeth
,
Langa, Ivan
,
Carrola, João Soares
in
Acetylcholinesterase - pharmacology
,
Adults
,
Amphetamines
2023
MDMA (3,4-methylenedioxymethamphetamine) is a chiral psychoactive recreational drug sold in illicit markets as racemate. Studies on the impact of MDMA on aquatic organisms are scarce. While enantioselectivity in toxicity in animals and humans has been reported, none is reported on aquatic organisms. This study aimed to investigate the ecotoxicological effects of MDMA and its enantiomers in Daphnia magna. For that, enantiomers (enantiomeric purity > 97%) were separated by liquid chromatography using a homemade semipreparative chiral column. Daphnids were exposed to three concentrations of (R,S)-MDMA (0.1, 1.0 and 10.0 µg L−1) and two concentrations of (R)- and (S)-enantiomers (0.1 and 1.0 µg L−1) over the course of 8 days. Morphophysiological responses were dependent on the substance form and daphnia development stage, and they were overall not affected by the (R)-enantiomer. Changes in swimming behaviour were observed for both the racemate and its enantiomers, but enantioselective effects were not observed. Reproductive or biochemical changes were not observed for enantiomers whereas a significant decrease in acetylcholinesterase and catalase activity was noted at the highest concentration of (R,S)-MDMA (10 µg L−1). Overall, this study showed that sub-chronic exposure to MDMA racemate and its enantiomers can interfere with morphophysiological and swimming behaviour of D. magna. In general, the (R)-enantiomer demonstrated less toxicity than the (S)-enantiomer.
Journal Article
The mixture of “ecstasy” and its metabolites is toxic to human SH-SY5Y differentiated cells at in vivo relevant concentrations
by
Fernandes, Eduarda
,
Bastos, Maria de Lourdes
,
Carvalho, Félix
in
Acetylcysteine - pharmacology
,
Biomedical and Life Sciences
,
Biomedicine
2014
The neurotoxicity of “ecstasy” (3,4-methylenedioxymethamphetamine, MDMA) is thought to involve hepatic metabolism, though its real contribution is not completely understood. Most in vitro neurotoxicity studies concern isolated exposures of MDMA or its metabolites, at high concentrations, not considering their mixture, as expected in vivo. Therefore, our postulate is that combined deleterious effects of MDMA and its metabolites, at low micromolar concentrations that may be attained into the brain, may elicit neurotoxicity. Using human SH-SY5Y differentiated cells as dopaminergic neuronal model, we studied the neurotoxicity of MDMA and its MDMA metabolites α-methyldopamine and
N
-methyl-α-methyldopamine and their correspondent glutathione and
N
-acetylcysteine monoconjugates, under isolated exposure and as a mixture, at normothermic or hyperthermic conditions. The results showed that the mixture of MDMA and its metabolites was toxic to SH-SY5Y differentiated cells, an effect potentiated by hyperthermia and prevented by
N
-acetylcysteine. As a mixture, MDMA and its metabolites presented a different toxicity profile, compared to each compound alone, even at equimolar concentrations. Caspase 3 activation, increased reactive oxygen species production, and intracellular Ca
2+
raises were implicated in the toxic effect. The mixture increased intracellular glutathione levels by increasing its de novo synthesis. In conclusion, this study demonstrated, for the first time, that the mixture of MDMA and its metabolites, at low micromolar concentrations, which represents a more realistic approach of the in vivo scenario, elicited toxicity to human SH-SY5Y differentiated cells, thus constituting a new insight into the context of MDMA-related neurotoxicity.
Journal Article
Cardiac effects of ephedrine, norephedrine, mescaline, and 3,4-methylenedioxymethamphetamine (MDMA) in mouse and human atrial preparations
by
Azatsian, Karyna
,
Hofmann, Britt
,
Gergs, Ulrich
in
Animals
,
Atrial Fibrillation
,
Biomedical and Life Sciences
2023
The use of recreational drugs like ephedrine, norephedrine, 3,4-methylenedioxymethamphetamine (MDMA), and mescaline can lead to intoxication and, at worst, to death. One reason for a fatal course of intoxication with these drugs might lie in cardiac arrhythmias. To the best of our knowledge, their inotropic effects have not yet been studied in isolated human cardiac preparations. Therefore, we measured inotropic effects of the hallucinogenic drugs ephedrine, norephedrine, mescaline, and MDMA in isolated mouse left atrial (mLA) and right atrial (mRA) preparations as well as in human right atrial (hRA) preparations obtained during cardiac surgery. Under these experimental conditions, ephedrine, norephedrine, and MDMA increased force of contraction (mLA, hRA) and beating rate (mRA) in a time- and concentration-dependent way, starting at 1–3 µM but these drugs were less effective than isoprenaline. Mescaline alone or in the presence of phosphodiesterase inhibitors did not increase force in mLA or hRA. The positive inotropic effects of ephedrine, norephedrine, or MDMA were accompanied by increases in the rate of tension and relaxation and by shortening of time of relaxation and, moreover, by an augmented phosphorylation state of the inhibitory subunit of troponin in hRA. All effects were greatly attenuated by cocaine (10 µM) or propranolol (10 µM) treatment. In summary, the hallucinogenic drugs ephedrine, norephedrine, and MDMA, but not mescaline, increased force of contraction and increased protein phosphorylation presumably, in part, by a release of noradrenaline in isolated human atrial preparations and thus can be regarded as indirect sympathomimetic drugs in the human atrium.
Journal Article
MDMA (Ecstasy) and human dopamine, norepinephrine, and serotonin transporters: implications for MDMA-induced neurotoxicity and treatment
by
Verrico, Christopher D.
,
Miller, Gregory M.
,
Madras, Bertha K.
in
Binding, Competitive
,
Brain
,
Brain - drug effects
2007
3,4-Methylenedioxymethamphetamine (MDMA, designated as \"Ecstasy\" if illicitly marketed in tablet form) induces significant decrements in neuronal serotonin (5-HT) markers in humans, nonhuman primates, and rats as a function of dosing and dosing regimen. In rats, MDMA-mediated effects are attributed, in part, to selective high-affinity transport of MDMA into 5-HT neurons by the 5-HT transporter (SERT), followed by extensive 5-HT release.
To clarify whether SERT-selective effects of MDMA at human monoamine transporters can account for the reported MDMA-induced selective toxicity of serotonin neurons in primate brain.
We investigated the interaction of [(3)H](+/-, RS)- (+, S)- and (-, R)-MDMA with the human SERT, dopamine (DA) transporter (DAT), and norepinephrine (NE) transporter (NET) in stably transfected human embryo kidney (HEK)-293 cells.
The human DAT, NET, and SERT actively transported [(3)H]RS(+/-)-MDMA saturably, stereoselectively, and in a temperature-, concentration-, and transporter-dependent manner. MDMA exhibited the highest affinity for the NET>>SERT>or=DAT, the same rank order for MDMA inhibition of [(3)H]DA, [(3)H]NE, and [(3)H]5-HT transport and stimulated release of the [(3)H]monoamines, which differed from reports derived from rodent monoamine transporters. The extent of MDMA-induced release of 5-HT was higher compared with release of DA or NE.
The affinity of MDMA for the human SERT in transfected cells does not clarify the apparent selective toxicity of MDMA for serotonin neurons, although conceivably, its higher efficacy for stimulating 5-HT release may be a distinguishing factor. The findings highlight the need to investigate MDMA effects in DAT-, SERT-, and NET-expressing neurons in the primate brain and the therapeutic potential of NET or DAT inhibitors, in addition to SERT-selective inhibitors, for alleviating the pharmacological effects of MDMA.
Journal Article
New types of drug use and risks of drug use among men who have sex with men: a cross-sectional study in Hangzhou, China
2018
Background
The use of new types of drugs has become more common among men who have sex with men (MSM). The aim of this study was to describe the patterns of the use of new types of drugs, such as methamphetamine, ketamine, ecstasy, and rush poppers, and to examine the factors associated with drug use and HIV infection among MSM in Hangzhou, China.
Methods
This cross-sectional study was conducted between August 2015 and April 2016. We used snowball sampling to recruit MSM; participants were recruited from voluntary counseling and testing centers, baths, bars, Blued (an app for the gay community), QQ groups, clubs, and other types of venues. MSM were included if their previous HIV test results were negative or unknown, or they had not been tested for HIV. MSM were excluded if they were known to be HIV positive before the survey. Face-to-face questionnaires were conducted and a venous blood specimen was drawn from each participant following the interview.
Results
In total, 555 MSM were included; 18.2% (101/555) of the participants had used new types of drugs in the past 3 months. Among the users, 65.3% used single-use rush poppers, while the remainder used ketamine, methamphetamine, ecstasy, or other mixed combinations of drugs. The HIV positivity rate was 14.8% (82/555). Factors associated with increased odds of using new types of drugs in the past 3 months were higher education levels (adjusted odds ratio [AOR] 4.45, 95% confidence interval [CI] 2.12–9.37), having multiple sexual partners (AOR 1.76, 95 CI 1.02–3.05), alcohol use before sexual intercourse (AOR 33.44, 95% CI 10.80–103.50), and seeing friends using new types of drugs.
Conclusion
We revealed the widespread use of new types of drugs, as well as a high diagnosis rate of new HIV infection, among MSM in Hangzhou. The use of new types of drugs was associated with an increased number of sexual partners among MSM; the high-risk sexual behaviors increased the risk of HIV infection. Attention should be given to the use of new types of drugs in MSM, and supervision programs should be strengthened to combat drug use.
Journal Article
\Ecstasy\-induced toxicity in SH-SY5Y differentiated cells: role of hyperthermia and metabolites
by
Bastos, Maria Lourdes
,
Fernandes, Eduarda
,
Carvalho, Félix
in
3,4-Methylenedioxyamphetamine - metabolism
,
3,4-Methylenedioxyamphetamine - toxicity
,
Acetylcysteine - metabolism
2014
3,4-Methylenedioxymethamphetamine (MDMA; “ecstasy”) is a recreational hallucinogenic drug of abuse known to elicit neurotoxic properties. Hepatic formation of neurotoxic metabolites is thought to play a major role in MDMA-related neurotoxicity, though the mechanisms involved are still unclear. Here, we studied the neurotoxicity mechanisms and stability of MDMA and 6 of its major human metabolites, namely α-methyldopamine (α-MeDA) and
N
-methyl-α-methyldopamine (N-Me-α-MeDA) and their correspondent glutathione (GSH) and
N
-acetyl-cysteine (NAC) conjugates, under normothermic (37 °C) or hyperthermic conditions (40 °C), using cultured SH-SY5Y differentiated cells. We showed that MDMA metabolites exhibited toxicity to SH-SY5Y differentiated cells, being the GSH and NAC conjugates more toxic than their catecholic precursors and MDMA. Furthermore, whereas the toxicity of the catechol metabolites was potentiated by hyperthermia, NAC-conjugated metabolites revealed higher toxicity under normothermia and GSH-conjugated metabolites-induced toxicity was temperature-independent. Moreover, a time-dependent decrease in extracellular concentration of MDMA metabolites was observed, which was potentiated by hyperthermia. The antioxidant NAC significantly protected against the neurotoxic effects of MDMA metabolites. MDMA metabolites increased intracellular glutathione levels, though depletion in thiol content was observed in MDMA-exposed cells. Finally, the neurotoxic effects induced by the MDMA metabolite N-Me-α-MeDA involved caspase 3 activation. In conclusion, this study evaluated the stability of MDMA metabolites in vitro, and demonstrated that the catechol MDMA metabolites and their GSH and NAC conjugates, rather than MDMA itself, exhibited neurotoxic actions in SH-SY5Y differentiated cells, which were differently affected by hyperthermia, thus highlighting a major role for reactive metabolites and hyperthermia in MDMA’s neurotoxicity.
Journal Article
Ecstasy metabolites and monoamine neurotransmitters upshift the Na+/K+ ATPase activity in mouse brain synaptosomes
by
Fernandes, Eduarda
,
de Lourdes Bastos, Maria
,
Carvalho, Félix
in
3,4-Dihydroxyphenylacetic Acid - metabolism
,
3,4-Dihydroxyphenylacetic Acid - pharmacology
,
3,4-dihydroxyphenylalanine oxidative deaminase
2022
3,4-Methylenedioximethamphetamine (MDMA; “ecstasy”) is a psychotropic drug with well-known neurotoxic effects mediated by hitherto not fully understood mechanisms. The Na
+
- and K
+
-activated adenosine 5′-triphosphatase (Na
+
/K
+
ATPase), by maintaining the ion gradient across the cell membrane, regulates neuronal excitability. Thus, a perturbation of its function strongly impacts cell homeostasis, ultimately leading to neuronal dysfunction and death. Nevertheless, whether MDMA affects the Na
+
/K
+
ATPase remains unknown. In this study, we used synaptosomes obtained from whole mouse brain to test the effects of MDMA, three of its major metabolites [α-methyldopamine,
N
-methyl-α-methyldopamine and 5-(glutathion-
S
-yl)-α-methyldopamine], serotonin (5-HT), dopamine, 3,4-dihydroxy-
l
-phenylalanine (
l
-Dopa) and 3,4-dihydroxyphenylacetic acid (DOPAC) on the Na
+
/K
+
ATPase function. A concentration-dependent increase of Na
+
/K
+
ATPase activity was observed in synaptosomes exposed to the tested compounds (concentrations ranging from 0.0625 to 200 µM). These effects were independent of protein kinases A and C activities. Nevertheless, a rescue of the compounds’ effects was observed in synaptosomes pre-incubated with the antioxidant
N
-acetylcysteine (1 mM), suggesting a role for reactive species-regulated pathways on the Na
+
/K
+
ATPase effects. In agreement with this hypothesis, a similar increase in the pump activity was found in synaptosomes exposed to the chemical generator of superoxide radicals, phenazine methosulfate (1–250 µM). This study demonstrates the ability of MDMA metabolites, monoamine neurotransmitters,
l
-Dopa and DOPAC to alter the Na
+
/K
+
ATPase function. This could represent a yet unknown mechanism of action of MDMA and its metabolites in the brain.
Journal Article
Protective effects of atorvastatin and rosuvastatin on 3,4-methylenedioxymethamphetamine (MDMA)-induced spatial learning and memory impairment
by
Mirjani, Ruhollah
,
Khorshidi, Laleh
,
Mirghazanfari, Mahdi
in
Allergology
,
Animals
,
Apoptosis - drug effects
2021
3,4‐Methylenedioxymethamphetamine (MDMA) or “Ecstasy”, which has been used for recreational purposes, is shown to impair memory and brain functions. Statins, beyond their efficient cholesterol-lowering impact through inhibition of HMG-COA reductase enzyme, possess multiple actions referred to as pleiotropic effects. In this regard, we aimed to investigate the neuroprotective effects of atorvastatin and rosuvastatin on MDMA-induced neurotoxicity. Adult male Wistar rats received atorvastatin (5, 10, and 20 mg/kg; orally) and rosuvastatin (5, 10, 20 mg/kg; orally) for 21 consecutive days. Then, spatial memory and learning were evaluated by Morris water maze (MWM) test. Rats were intraperitoneally injected with MDMA (2.5, 5, and 10 mg/kg) 30 min before the first training session in 4 training days of MWM task. Afterward, rats were euthanized and their hippocampuses were dissected to evaluate reactive oxygen species (ROS) production, lipid peroxidation (LPO), and caspase-3 and -9 activities. Our findings showed that MDMA (5 and 10 mg/kg) significantly impaired spatial memory functions and dramatically increased ROS production, LPO, and caspase-3 and -9 activities compared to control. Also, atorvastatin (5, 10, and 20 mg/kg) and rosuvastatin (20 mg/kg) significantly improved memory performances and inhibited the elevation of ROS, LPO, and caspase-3 and -9 activities induced by MDMA. In conclusion, the results indicated that MDMA-induced cognitive impairment is followed by oxidative stress and activation of apoptotic pathways in the hippocampus. However, atorvastatin and rosuvastatin suppressed these deleterious consequences of MDMA and revealed protective effects against activation of pathways leading to cell damage.
Journal Article
New Insights on Different Response of MDMA-Elicited Serotonin Syndrome to Systemic and Intracranial Administrations in the Rat Brain
by
Shokry, Ibrahim M.
,
Tao, Rui
,
Callanan, John J.
in
Animals
,
Biology and Life Sciences
,
Body Temperature
2016
In spite of the fact that systemic administration of MDMA elicits serotonin syndrome, direct intracranial administration fails to reproduce the effect. To reconcile these findings, it has been suggested that the cause of serotonin syndrome is attributed mainly to MDMA hepatic metabolites, and less likely to MDMA itself. Recently, however, this explanation has been challenged, and alternative hypotheses need to be explored. Here, we tested the hypothesis that serotonin syndrome is the result of excessive 5HT simultaneously in many brain areas, while MDMA administered intracranially fails to cause serotonin syndrome because it produces only a localized effect at the delivery site and not to other parts of the brain. This hypothesis was examined using adult male Sprague Dawley rats by comparing 5HT responses in the right and left hemispheric frontal cortices, right and left hemispheric diencephalons, and medullar raphe nucleus. Occurrence of serotonin syndrome was confirmed by measuring change in body temperature. Administration routes included intraperitoneal (IP), intracerebroventricular (ICV) and reverse microdialysis. First, we found that IP administration caused excessive 5HT in all five sites investigated and induced hypothermia, suggesting the development of the serotonin syndrome. In contrast, ICV and reverse microdialysis caused excessive 5HT only in regions of delivery sites without changes in body-core temperature, suggesting the absence of the syndrome. Next, chemical dyes were used to trace differences in distribution and diffusion patterns between administration routes. After systemic administration, the dyes were found to be evenly distributed in the brain. However, the dyes administered through ICV or reverse microdialysis injection still remained in the delivery sites, poorly diffusing to the brain. In conclusion, intracranial MDMA administration in one area has no or little effect on other areas, which must be considered a plausible reason for the difference in MDMA-elicited serotonin syndrome between systemic and intracranial administrations.
Journal Article