Urinary excretion kinetics of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) and its phase I and phase II metabolites in humans following controlled MDMA administration

Bioisosteric analogs of MDMA: Improving the pharmacological profile?

3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') is re-emerging in clinical settings as a candidate for the treatment of specific neuropsychiatric disorders (e.g. post-traumatic stress disorder) in combination with psychotherapy. MDMA is a psychoactive drug, typically regarded as an empathogen or entactogen, which leads to transporter-mediated monoamine release. Despite its therapeutic potential, MDMA can induce dose-, individual-, and context-dependent untoward effects outside safe settings. In this study, we investigated whether three new methylenedioxy bioisosteres of MDMA improve its off-target profile. In vitro methods included radiotracer assays, transporter electrophysiology, bioluminescence resonance energy transfer and fluorescence-based assays, pooled human liver microsome/S9 fraction incubations, metabolic stability studies, isozyme mapping, and liquid chromatography coupled to high-resolution mass spectrometry. In silico methods included molecular docking. Compared with MDMA, all three MDMA bioisosteres (ODMA, TDMA, and SeDMA) showed similar pharmacological activity at human serotonin, dopamine, and norepinephrine transporters (hSERT, hDAT, and hNET, respectively) but decreased agonist activity at 5-HT2A/2B/2C receptors. Regarding their hepatic metabolism, they differed from MDMA, with N-demethylation being the only metabolic route shared, and without forming phase II metabolites. In addition, TDMA showed an enhanced intrinsic clearance in comparison to its congeners. Additional screening for their interaction with human organic cation transporters (hOCTs) and plasma membrane monoamine transporter (hPMAT) revealed a weaker interaction of the MDMA analogs with hOCT1, hOCT2, and hPMAT. Our findings suggest that these new MDMA bioisosteres might constitute appealing therapeutic alternatives to MDMA, sparing the primary pharmacological activity at hSERT, hDAT, and hNET, but displaying a reduced activity at 5-HT2A/2B/2C receptors and alternative hepatic metabolism. Whether these MDMA bioisosteres may pose lower risk alternatives to the clinically re-emerging MDMA warrants further studies.

Bioisosteric analogs of MDMA with improved pharmacological profile

3,4-Methylenedioxymethamphetamine (MDMA, ' ecstasy' ) is re-emerging in clinical settings as a candidate for the treatment of specific psychiatric disorders (e.g. post-traumatic stress disorder) in combination with psychotherapy. MDMA is a psychoactive drug, typically regarded as an empathogen or entactogen, which leads to transporter-mediated monoamine release. Despite its therapeutic potential, MDMA can induce dose-, individual-, and context-dependent untoward effects outside safe settings. In this study, we investigated whether three new methylenedioxy bioisosteres of MDMA improve its off-target profile. In vitro methods included radiotracer assays, transporter electrophysiology, bioluminescence resonance energy transfer and fluorescence-based assays, pooled human liver microsome/S9 fraction incubation with isozyme mapping, and liquid chromatography coupled to high-resolution mass spectrometry. In silico methods included molecular docking. Compared with MDMA, all three MDMA bioisosteres (ODMA, TDMA, and SeDMA) showed similar pharmacological activity at human serotonin and dopamine transporters (hSERT and hDAT, respectively) but decreased activity at 5-HT 2A/2B/2C receptors. Regarding their hepatic metabolism, they differed from MDMA, with N -demethylation being the only metabolic route shared, and without forming phase II metabolites. Additional screening for their interaction with human organic cation transporters (hOCTs) and plasma membrane transporter (hPMAT) revealed a weaker interaction of the MDMA analogs with hOCT1, hOCT2, and hPMAT. Our findings suggest that these new MDMA analogs might constitute appealing therapeutic alternatives to MDMA, sparing the primary pharmacological activity at hSERT and hDAT, but displaying a reduced activity at 5-HT 2A/2B/2C receptors and reduced hepatic metabolism. Whether these MDMA bioisosteres may pose lower risk alternatives to the clinically re-emerging MDMA warrants further studies.

Analysis of drug of abuse compounds using passive sampling and ultrahigh-liquid chromatography coupled to mass spectrometry

The present study proposes the monitoring of compounds of drugs of abuse through the use of passive samplers in water systems. Initially, four positive ion compounds of interest were determined according to national surveys, and then composite sampling and passive sampling were implemented using continuous-flow passive samplers containing two types of sorbents, the Empore disk and Gerstel Twister. Two study sites were established at the beginning and at the end of the middle Bogotá River basin. After 4 days, the sorbents were removed so that they could be desorbed and analyzed using UHPLC-MS in the laboratory. For the composite samples, the results were below the first calibration curve point (FCCP) of the chromatographic method, and for passive sampling, peaks of benzoylecgonine (BE) (21427.3 pg mL-1), methamphetamine (MET) (67101.5 pg mL-1), MDMA (ecstasy) (225844.8 pg mL-1) and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) (15908.4 pg mL-1) were found. Therefore, passive sampling could be suggested as an alternative to composite sampling for the monitoring of compounds.

Microextraction Techniques for Sample Preparation of Amphetamines in Urine: A Comprehensive Review

Psychological disorders and dramatic social problems are serious concerns regarding the abuse of amphetamine and its stimulant derivatives worldwide. Consumers of such drugs experience great euphoria along with serious health problems. Determination and quantification of amphetamine-type stimulants are indispensable skills for clinical and forensic laboratories. Analysis of low drug doses in bio-matrices necessitates applications of simple and also effective preparation steps. The preparation procedures not only eliminate adverse matrix effects, but also provide reasonable clean-up and pre-concentration benefits. The current review presents different methods used for sample preparation of amphetamines from urine as the most frequently used biological matrix. The advantages and limitations of various sample preparation methods were discussed focusing on the miniaturized methods.

3,4-methylenedioxymethamphetamine (MDMA)-induced macular haemorrhage: A case report

A case of 28-year-old female patient with retinal haemorrhage after taking 3,4-methylenedioxymethamphetamine (ecstasy, MDMA) and having a sexual intercourse is described. Ecstasy is a drug that is often consumed by young people. It leaves various consequences on the human body. Retinal haemorrhage in the eye caused by ecstasy has been described before. Like in this case, the experience in spontaneous resolving of the MDMA-induced retinal haemorrhage is favourable.

Studies with psychedelic drugs in human volunteers

Scientific curiosity and fascination have played a key role in human research with psychedelics along with the hope that perceptual alterations and heightened insight could benefit well-being and play a role in the treatment of various neuropsychiatric disorders. These motivations need to be tempered by a realistic assessment of the hurdles to be cleared for therapeutic use. Development of a psychedelic drug for treatment of a serious psychiatric disorder presents substantial although not insurmountable challenges. While the varied psychedelic agents described in this chapter share some properties, they have a range of pharmacologic effects that are reflected in the gradation in intensity of hallucinogenic effects from the classical agents to DMT, MDMA, ketamine, dextromethorphan and new drugs with activity in the serotonergic system. The common link seems to be serotonergic effects modulated by NMDA and other neurotransmitter effects. The range of hallucinogens suggest that they are distinct pharmacologic agents and will not be equally safe or effective in therapeutic targets. Newly synthesized specific and selective agents modeled on the legacy agents may be worth considering. Defining therapeutic targets that represent unmet medical need, addressing market and commercial issues, and finding treatment settings to safely test and use such drugs make the human testing of psychedelics not only interesting but also very challenging. This article is part of the Special Issue entitled 'Psychedelics: New Doors, Altered Perceptions'.

Pooled human liver preparations, HepaRG, or HepG2 cell lines for metabolism studies of new psychoactive substances? A study using MDMA, MDBD, butylone, MDPPP, MDPV, MDPB, 5-MAPB, and 5-API as examples

Metabolism studies play an important role in clinical and forensic toxicology. Because of potential species differences in metabolism, human samples are best suitable for elucidating metabolism. However, in the case of new psychoactive substances (NPS), human samples of controlled studies are not available. Primary human hepatocytes have been described as gold standard for in vitro metabolism studies, but there are some disadvantages such as high costs, limited availability, and variability of metabolic enzymes. Therefore, the aim of our study was to investigate and compare the metabolism of six methylenedioxy derivatives (MDMA, MDBD, butylone, MDPPP, MDPV, MDPB) and two bioisosteric analogues (5-MAPB, 5-API) using pooled human liver microsomes (pHLM) combined with cytosol (pHLC) or pooled human liver S9 fraction (pS9) all after addition of co-substrates for six phase I and II reactions. In addition, HepaRG and HepG2 cell lines were used. Results of the different in vitro tools were compared to each other, to corresponding published data, and to metabolites identified in human urine after consumption of MDMA, MDPV, or 5-MAPB. Incubations with pHLM plus pHLC showed similar results as pS9. A more cost efficient model for prediction of targets for toxicological screening procedures in human urine should be identified. As expected, the incubations with HepaRG provided better results than those with HepG2 concerning number and signal abundance of the metabolites. Due to easy handling without special equipment, incubations with pooled liver preparations should be the most suitable alternative to find targets for toxicological screening procedures for methylenedioxy derivatives and bioisosteric analogues.

Monitoring MDMA metabolites in urban wastewater as novel biomarkers of consumption

Consumption of 3,4-methylendioxymethamphetamine (MDMA) has been always estimated by measuring the parent substance through chemical analysis of wastewater. However, this may result in an overestimation of the use if the substance is directly disposed in sinks or toilets. Using specific urinary metabolites may overcome this limitation. This study investigated for the first time the suitability of a panel of MDMA metabolites as biomarkers of consumption, considering the specific criteria recently proposed, i.e. being detectable and stable in wastewater, being excreted in a known percentage in urine, and having human excretion as the sole source. A new analytical method was developed and validated for the extraction and analysis of MDMA and three of its main metabolites in wastewater. 24-h composite raw wastewater samples from three European cities were analysed and MDMA use was back-calculated. Results from single MDMA loads, 4-hydroxy-3-methoxymethamphetamine (HMMA) loads and from the sum of MDMA, HMMA and 4-hydroxy-3-methoxyamphetamine (HMA) loads were in line with the well-known recreational use of this drug: consumption was higher during the weekend in all cities. HMMA and HMA turned out to be suitable biomarkers of consumption; however, concentrations measured in wastewater did not resemble the expected pharmacokinetic profiles, quite likely due to the very limited information available on excretion profiles. Different options were tested to back-calculate MDMA use, including the sum of MDMA and its metabolites, to balance the biases associated with each single substance. Nevertheless, additional pharmacokinetic studies are urgently needed in order to get more accurate excretion rates and, therefore, improve the estimates of MDMA use.

Refining correction factors for back-calculation of illicit drug use

The estimation of illicit drugs use through wastewater analysis has become an important issue in the last few years due to their large worldwide consumption, which results in economic, social and health costs. The amounts of urinary biomarkers of illicit drugs (selected drugs or their metabolites) measured in wastewater are used to back-calculate the consumption of a particular drug by the population and to monitor temporal and spatial trends of illicit drug use in a community. The reliability of back-calculation depends on different factors, one being the accuracy of correction factors. A wide range of correction factors have been used in different studies and some biases must be expected when comparing results. Most of the correction factors were developed several years ago, so they need to be updated to include the latest information on pharmacokinetics. Moreover, new comprehensive methods to treat data should be adopted. The goal of this study is to refine current correction factors for back-calculation of the most widely used illicit drugs: amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and tetrahydrocannabinol (THC). The mean percentages of excretion of the parent drugs and their metabolites were calculated for each route of administration, utilizing all accessible pharmacokinetic studies in the literature. This allowed to select the most suitable drug target residue and a refined correction factor was obtained for each substance considering the most frequent route of administration. The refined correction factors we propose can be used in wastewater based epidemiology to standardize the back-calculation of these drugs. These results can be included in the best practice protocol currently adopted in EU studies in order to reduce uncertainty and improve the comparability of results.

Impact of Cytochrome P450 2D6 Function on the Chiral Blood Plasma Pharmacokinetics of 3,4-Methylenedioxymethamphetamine (MDMA) and Its Phase I and II Metabolites in Humans

3,4-methylenedioxymethamphetamine (MDMA; ecstasy) metabolism is known to be stereoselective, with preference for S-stereoisomers. Its major metabolic step involves CYP2D6-catalyzed demethylenation to 3,4-dihydroxymethamphetamine (DHMA), followed by methylation and conjugation. Alterations in CYP2D6 genotype and/or phenotype have been associated with higher toxicity. Therefore, the impact of CYP2D6 function on the plasma pharmacokinetics of MDMA and its phase I and II metabolites was tested by comparing extensive metabolizers (EMs), intermediate metabolizers (IMs), and EMs that were pretreated with bupropion as a metabolic inhibitor in a controlled MDMA administration study. Blood plasma samples were collected from 16 healthy participants (13 EMs and three IMs) up to 24 h after MDMA administration in a double-blind, placebo-controlled, four-period, cross-over design, with subjects receiving 1 week placebo or bupropion pretreatment followed by a single placebo or MDMA (125 mg) dose. Bupropion pretreatment increased the maximum plasma concentration (C_max) and area under the plasma concentration-time curve from 0 to 24 h (AUC₂₄) of R-MDMA (9% and 25%, respectively) and S-MDMA (16% and 38%, respectively). Bupropion reduced the C_max and AUC₂₄ of the CYP2D6-dependently formed metabolite stereoisomers of DHMA 3-sulfate, DHMA 4-sulfate, and 4-hydroxy-3-methoxymethamphetamine (HMMA sulfate and HMMA glucuronide) by approximately 40%. The changes that were observed in IMs were generally comparable to bupropion-pretreated EMs. Although changes in stereoselectivity based on CYP2D6 activity were observed, these likely have low clinical relevance. Bupropion and hydroxybupropion stereoisomer pharmacokinetics were unaltered by MDMA co-administration. The present data might aid further interpretations of toxicity based on CYP2D6-dependent MDMA metabolism.

Screening for illicit drugs in pooled human urine and urinated soil samples and studies on the stability of urinary excretion products of cocaine, MDMA, and MDEA in wastewater by hyphenated mass spectrometry techniques

Monitoring population drug use through wastewater-based epidemiology (WBE) is a useful method to quantitatively follow trends and estimate total drug consumption in communities. Concentrations of drug biomarkers might be low in wastewater due to dilution; and therefore analysis of pooled urine (PU) is useful to detect consumed drugs and identify targets of illicit drugs use. The aims of the study were (1) to screen PU and urinated soil (US) samples collected at festivals for illicit drug excretion products using hyphenated techniques; (2) to develop and validate a hydrophilic interaction liquid chromatography - mass spectrometry / mass spectrometry (HILIC-MS/MS) method of quantifying urinary targets of identified drugs in wastewater; and (3) to conduct a 24 h stability study, using PU and US to better reflect the chemical environment for targets in wastewater. Cocaine (COC) and ecstasy-like compounds were the most frequently detected illicit drugs; an analytical method was developed to quantify their excretion products. Hydroxymethoxymethamphetamine (HMMA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), HMMA sulfate (HMMA-S), benzoylecgonine (BE), and cocaethylene (CE) had 85-102% of initial concentration after 8 h of incubation, whereas COC and ecgonine methyl ester (EME) had 74 and 67% after 8 h, respectively. HMMA showed a net increase during 24 h of incubation (107% ± 27, n = 8), possibly due to the cleavage of HMMA conjugates, and biotransformation of MDMA. The results suggest HMMA as analytical target for MDMA consumption in WBE, due to its stability in wastewater and its excretion as the main phase I metabolite of MDMA. Copyright © 2016 John Wiley & Sons, Ltd.

A Metabolomics Study of Retrospective Forensic Data from Whole Blood Samples of Humans Exposed to 3,4-Methylenedioxymethamphetamine: A New Approach for Identifying Drug Metabolites and Changes in Metabolism Related to Drug Consumption

The illicit drug 3,4-methylenedioxymethamphetamine (MDMA) has profound physiological cerebral, cardiac, and hepatic effects that are reflected in the blood. Screening of blood for MDMA and other narcotics are routinely performed in forensics analysis using ultra-performance liquid chromatography with high-resolution time-of-flight mass spectrometry (UPLC-HR-TOFMS). The aim of this study was to investigate whether such UPLC-HR-TOFMS data collected over a two-year period could be used for untargeted metabolomics to determine MDMA metabolites as well as endogenous changes related to drug response and toxicology. Whole blood samples from living Danish drivers' positive for MDMA in different concentrations were compared to negative control samples using various statistical methods. The untargeted identification of known MDMA metabolites was used to validate the methods. The results further revealed changes of several acylcarnitines, adenosine monophosphate, adenosine, inosine, thiomorpholine 3-carboxylate, tryptophan, S-adenosyl-l-homocysteine (SAH), and lysophospatidylcholine (lysoPC) species in response to MDMA. These endogenous metabolites could be implicated in an increased energy demand and mechanisms related to the serotonergic syndrome as well as drug induced neurotoxicity. The findings showed that it was possible to extract meaningful results from retrospective UPLC-HR-TOFMS screening data for metabolic profiling in relation to drug metabolism, endogenous physiological effects, and toxicology.

Strategies for ascertaining the interference of phase II metabolites co-eluting with parent compounds using LC-MS/MS

LC-MS/MS is currently the most selective and efficient tool for the quantitative analysis of drugs and metabolites in the pharmaceutical industry and in clinical assays. However, phase II metabolites sometimes negatively affect the selectivity and efficiency of the LC-MS/MS method, especially for the metabolites that possess similar physicochemical characteristics and generate the same precursor ions as their parent compounds due to the in-source collision-induced dissociation during the ionization process. This paper proposes some strategies for examining co-eluting metabolites existing in real samples, and further assuring whether these metabolites could affect the selectivity and accuracy of the analytical methods. Strategies using precursor-ion scans and product-ion scans were applied in this study. An example drug, namely, caffeic acid phenethyl ester, which can generate many endogenous phase II metabolites, was selected to conduct this work. These metabolites, generated during the in vivo metabolic processes, can be in-source-dissociated to the precursor ions of their parent compounds. If these metabolites are not separated from their parent compounds, the quantification of the target analytes (parent compounds) would be influenced. Some metabolites were eluted closely to caffeic acid phenethyl ester on LC columns, although long columns and relatively long elution programs were used. The strategies can be utilized in quantitative methodologies that apply LC-MS/MS to assure the performance of selectivity, thus enhancing the reliability of the experimental data.

Pharmacokinetics and pharmacodynamics of 3,4-methylenedioxymethamphetamine (MDMA): interindividual differences due to polymorphisms and drug-drug interactions

Clinical outcome following 3,4-methylenedioxymethamphetamine (MDMA) intake ranges from mild entactogenic effects to a life-threatening intoxication. Despite ongoing research, the clinically most relevant mechanisms causing acute MDMA-induced adverse effects remain largely unclear. This complicates the triage and treatment of MDMA users needing medical care. The user's genetic profile and interactions resulting from polydrug use are key factors that modulate the individual response to MDMA and influence MDMA pharmacokinetics and dynamics, and thus clinical outcome. Polymorphisms in CYP2D6, resulting in poor metabolism status, as well as co-exposure of MDMA with specific substances (e.g. selective serotonin reuptake inhibitors (SSRIs)) can increase MDMA plasma levels, but can also decrease the formation of toxic metabolites and subsequent cellular damage. While pre-exposure to e.g. SSRIs can increase MDMA plasma levels, clinical effects (e.g. blood pressure, heart rate, body temperature) can be reduced, possibly due to a pharmacodynamic interaction at the serotonin reuptake transporter (SERT). Pretreatment with inhibitors of the dopamine or norepinephrine reuptake transporter (DAT or NET), 5-HT(2A) or α-β adrenergic receptor antagonists or antipsychotics prior to MDMA exposure can also decrease one or more MDMA-induced physiological and/or subjective effects. Carvedilol, ketanserin and haloperidol can reduce multiple MDMA-induced clinical and neurotoxic effects. Thus besides supportive care, i.e. sedation using benzodiazepines, intravenous hydration, aggressive cooling and correction of electrolytes, it is worthwhile to investigate the usefulness of carvedilol, ketanserin and haloperidol in the treatment of MDMA-intoxicated patients.

Investigations on the stereoselectivity of the phase II metabolism of the 3,4-methylenedioxyethylamphetamine (MDEA) metabolites 3,4-dihydroxyethylamphetamine (DHEA) and 4-hydroxy-3-methoxyethylamphetamine (HMEA)

Different elimination was reported for the two enantiomers of the designer drug 3,4-methylenedioxyethylamphetamine (MDEA) in vivo. In the present work, the enantioselectivity of glucuronidation and sulfation of the MDEA phase I metabolites 3,4-dihydroxyethylamphetamine (DHEA) and 4-hydroxy-3-methoxyethylamphetamine (HMEA) was investigated. First, glucuronide standards were synthesized using rat liver microsomes. Incubations were performed with recombinant human UDP-glucuronyltransferases (UGT) and pooled human liver microsomes (pHLM) for glucuronidation and using recombinant human sulfotransferases (SULT) and pooled human liver cytosol (pHLC) for sulfation. Product formation experiments were performed by quantification of the phase II metabolites using liquid chromatography-high-resolution mass spectrometry. Additionally, substrate depletion experiments were conducted by gas chromatography-mass spectrometry after chiral derivatization for sulfation. UGT2B7, 2B15, and 2B17 were involved in glucuronidation of HMEA and SULT1A1 and SULT1A3 and SULT1A3 and SULT1E1 in the sulfation of DHEA and HMEA, respectively. SULTs provided much higher affinity, whereas UGTs showed higher capacities. Marked stereoselectivity could be observed for UGT2B15, UGT2B17, and pHLM toward S-HMEA, for SULT1A3 and pHLC toward S-DHEA and for SULT1A3 and pHLC toward R-HMEA. In conclusion, the phase II metabolism might also contribute to the observed different pharmacokinetic properties of MDEA.

Stereoselective urinary MDMA (ecstasy) and metabolites excretion kinetics following controlled MDMA administration to humans

The R- and S-enantiomers of racemic 3,4-methylenedioxymethamphetamine (MDMA) exhibit different dose-concentration curves. In plasma, S-MDMA was eliminated at a higher rate, most likely due to stereoselective metabolism. Similar data were shown in various in vitro experiments. The aim of the present study was the in vivo investigation of stereoselective elimination of MDMA's phase I and phase II metabolites in human urine following controlled oral MDMA administration. Urine samples from 10 participants receiving 1.0 and 1.6 mg/kg MDMA separated by at least one week were analyzed blind by liquid chromatography-high resolution-mass spectrometry and gas chromatography-mass spectrometry after chiral derivatization with S-heptafluorobutyrylprolyl chloride. R/S ratios at C(max) were comparable after low and high doses with ratios >1 for MDMA, free DHMA, and HMMA sulfate, and with ratios <1 for MDA, free HMMA, DHMA sulfate and HMMA glucuronide. In the five days after the high MDMA dose, a median of 21% of all evaluated compounds were excreted as R-stereoisomers and 17% as S-stereoisomers. Significantly greater MDMA, DHMA, and HMMA sulfate R-enantiomers and HMMA and HMMA glucuronide S-stereoisomers were excreted. No significant differences were observed for MDA and DHMA sulfate stereoisomers. Changes in R/S ratios could be observed over time for all analytes, with steady increases in the first 48 h. R/S ratios could help to roughly estimate time of MDMA ingestion and therefore, improve interpretation of MDMA and metabolite urinary concentrations in clinical and forensic toxicology.