An updated review on synthetic cathinones

Danio rerio embryo as in vivo model for the evaluation of the toxicity and metabolism of pyrovalerone cathinones

The objective of the present manuscript was the evaluation of the toxicity and metabolism of the second generation of pyrovalerone cathinones (α-PHP, α-PHPiP, 4-MePPP and TH-PVP), using an early zebrafish (Danio rerio) larvae as in vivo model. Pyrovalerone cathinones LC50 were determined after 24, 48, 72 and 96 h of exposure. TH-PVP proved to be the most toxic cathinone, whereas 4-MePPP was the least toxic. During acute exposure to pyrovalerone cathinones the main signs of toxicity exhibited by survivors were pericardial edema, yolk sac in embryos, bradycardia, delay in the hatching, malformations, and larvae without touch response. Afterwards, a short-term non-lethal experiment (24 h) was performed with early zebrafish larvae (72 h) for each of the selected compounds. The produced metabolites were tentatively identified by liquid chromatography-high resolution mass spectrometry (LC-HRMS) and the metabolic pathways were proposed. The results showed that hydroxylation and dihydroxylation can be considered the main metabolic pathways, although depending of the cathinone studied, other metabolites can be found.

Identification of synthetic cathinone positional isomers using electron activated dissociation mass spectrometry

BACKGROUND

Synthetic cathinones (SCs) are a large category of new psychoactive substances (NPS), which pose a serious threat to public health due to limited information about their toxicology and pharmacology. Many SCs are closely related in their chemical structures, with some substances being positional isomers. In this study, we propose a new workflow for the identification of SC isomers using liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS2) combined with electron activated dissociation (EAD) and chemometrics. Differentiation between isomeric SCs is essential for both legislative and public safety reasons, since minor differences in their molecular structures may change their legal status and pharmacological profiles.

RESULTS

The workflow was optimized using ring-substituted isomers of methylmethcathinones, methylethcathinones, and chloromethcathinones. The kinetic energy in the EAD cell was investigated at three levels (i.e., 15, 18, and 20 eV) for each group. Two data analysis methods (i.e., t-distributed stochastic neighbor embedding [t-SNE] and a Random Forest [RF] algorithm) were applied using the obtained EAD mass spectral data. The three sets of ring-substituted SCs were clearly distinguished using t-SNE and an RF algorithm. Moreover, the RF approach resulted in a 97 % classification accuracy for isomer identification using various combinations of compounds, isomers, and electron kinetic energies. This workflow was subsequentially applied to the analysis of 26 blind street samples, resulting in a 92 % classification accuracy for isomer identification. However, the accuracy varied based on the kinetic electron energy. A subset of the original data set, focusing on 15-eV data only, was used, resulting in a classification accuracy of 100 %.

SIGNIFICANCE

This study presents the first LC-HRMS2 workflow based on EAD and chemometrics, which resulted in a classification accuracy of 100 % of authentic street samples. The developed LC-HRMS2 workflow demonstrates that EAD product ions and their characteristic ion ratios can be successfully used to identify ring-substituted positional isomers of SCs.

Detection of the synthetic cathinone N,N-dimethylpentylone in seized samples from prisons

Drug use is prevalent in prisons with drugs associated with depressant effects found to be more prevalent than stimulants. Synthetic cathinones (SCats; often sold as "bath salts", "ecstasy", "molly", and "monkey dust") are the second largest category of new psychoactive substances (NPS) currently monitored by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) and are commonly used as substitutes for regulated stimulants, such as amphetamine, cocaine, and MDMA. N,N-dimethylpentylone (also known as dimethylpentylone, dipentylone, and bk-DMBDP) was detected for the first time in the Scottish prisons in seven powder samples seized between January and July 2023. Samples were analyzed using gas chromatography-mass spectrometry (GC-MS), ultra-high performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-QToF-MS), and nuclear magnetic resonance imaging (NMR). Dimethylpentylone was detected alongside other drugs in four samples, including the novel benzodiazepine desalkylgidazepam (bromonordiazepam) and the synthetic cannabinoid receptor agonists (SCRAs) MDMB-INACA and MDMB-4en-PINACA.

Low-triggering-potential electrochemiluminescence based on mental-organic frameworks encapsulation of ruthenium for synthetic cathinone detection by coupling photonic crystal light-scattering signal amplification of covalent-organic frameworks

Developing effective electrochemiluminescence (ECL) platforms is always an essential concern in highly sensitive bioanalysis. In this work, a low-triggering-potential ECL sensor was designed for detecting synthetic cathinone 3,4-methylenedioxypyrovalerone (MDPV) based on a dual-signal amplification strategy. Initially, a probe was created by integrating Ruthenium into the hollow porphyrin-based MOF (PCN-222) structure to decrease the excitation potential and enhance ECL performance without external co-reaction accelerators. Additionally, for the first time, photonic crystals (PCs) assembled from covalent organic frameworks (COFs) were employed to amplify the ECL signal, thereby increasing the photon flux and the loading capacity of the ECL emitter to enhance sensitivity of the sensor. In the presence of the target MDPV, the aptamer labeled with Ferrocene (Fc) experienced conformational changes, causing Fc to approach the luminophore and resulting in ECL quenching. This effect was attributed to aptamer's conformational changes induced by the target, directly correlating with the target concentration. The constructed sensor showed good linearity with the target MDPV concentration, covering a dynamic range from 1.0 × 10-14 to 1.0 × 10-6 g/L and achieved an ultra-low detection limit of 4.79 × 10-15 g/L. This work employed dual amplification strategies to enhance ECL signals effectively, providing a novel method for developing highly responsive and bioactive sensors.

2-Methyl-4'-(methylthio)-2-morpholinopropiophenone: A commercial photoinitiator being used as a new psychoactive substance

Synthetic cathinones, which are novel psychoactive substances, have caused major social problems worldwide. A substance called 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MMMP), which is employed as a commercial industrial photoinitiator for triggering polymerization, has a basic cathinone backbone; however, few reports regarding MMMP have been published. In the current study, three potential metabolites of MMMP-namely hydroxy-MMMP (HO-MMMP), HO-MMMP-sulfoxide (HO-MMMP-SO), and HO-MMMP-sulfone (HO-MMMP-SO2)-were successfully synthesized, and MMMP and these three potential metabolites were used as standards to establish an analytic method based on liquid chromatography-tandem mass spectrometry for the quantitative analysis of urine. This analytic method and related parameters-including dynamic range, limit of quantification, selectivity, precision, accuracy, carryover effect, matrix effect, interference, and dilution integrity-were optimized and validated. Forty urine samples from 1,691 individuals who abused drugs were determined to contain MMMP, HO-MMMP, HO-MMMP-SO, or HO-MMMP-SO2; the results of this study indicate that approximately 2.37 % of drug abusers in Taiwan consumed MMMP in 2023. These 40 urine samples were analyzed to investigate the metabolism of MMMP in humans. The results indicate that HO-MMMP-SO is the main metabolite in human urine. This study recommends HO-MMMP-SO with a concentration of 2 ng/mL as a target and cutoff value, respectively, for identifying individuals who have consumed MMMP.

Synthetic cathinones in drug-facilitated sexual assault: A case report involving the novel generation substituted cathinone N-ethylpentedrone and a review of the literature

The use of 3,4-methylenedioxymethamphetamine (MDMA) in drug-facilitated sexual assault (DFSA) is not uncommon. Indeed, the effects associated with the use of this substance may lead to disinhibition. Several synthetic cathinones, such as mephedrone or methylone, also possess marked entactogenic properties. This manuscript aims to (i) report a DFSA case involving a novel cathinone derivative, namely N-ethyl-pentedrone (NEPD) and (ii) review previously reported DFSA cases involving synthetic cathinones. Using liquid chromatography-high-resolution mass spectrometry (LC-HRMS), NEPD was detected in both plasma and urine collected from a 36-year-old male who had been victim of DFSA. Furthermore, an exhaustive, non-period-specific English-language literature search was performed using several different electronic databases to identify DFSA cases involving synthetic cathinones. Overall, five synthetic cathinones have been associated with DFSA:methylenedioxypyrovalerone, 4-methylethcathinone, α -pyrrolidinopentiophenone, mephedrone, α -pyrrolidinohexiophenone, and methylone, which appears to be the most frequently reported. Methylone is the β-keto analog of MDMA, with which it shares substantial pharmacological similarities. Indeed, the pharmacological effects of methylone are similar to those associated with MDMA. By contrast, little is known regarding NEPD's pharmacological effects in humans. Based on subjective reports, NEPD can produce both positive and negative effects in human. Unlike what is reported in the case of methylone or mephedrone, only a small minority of NEPD users report slightly entactogenics effects. Such properties theoretically make NEPD more suitable for use in a chemsex context than in DFSA context; even though, the boundary between these two specific forms of sexualized drug use can sometimes appear tenuous.

Clinical manifestations and analytical reports for MDPHP acute intoxication cases

MDPHP is a synthetic cathinone (SC) belonging to α-pyrrolidinophenone derivatives. It is a central nervous system stimulant and may induce hallucinations, paranoia, tachycardia, hypertension, chest pain, and rhabdomyolysis. In literature, a few cases of intoxication have been reported. In the present study, 17 cases of MDPHP intake were described including the analytical findings and clinical manifestations. MDPHP was quantified by liquid chromatography-tandem mass spectrometry in blood (range 1.26-73.30 ng/mL) and urine (range 19.31-8769.64 ng/mL) samples. In three cases the presence of α-PHP was observed. In one case, MDPHP was the only detected substance. Concomitant use of MDPHP with other substances, particularly psychostimulants, was common and it was difficult to describe the peculiar clinical characteristics of this SC. Most of the symptoms overlapped those expected, some of them were unusual and all of them particularly severe thus inducing the research of NPS in laboratory tests. We demonstrated the presence of psychiatric, neurological, and respiratory symptoms, as well as the possible presence of rhabdomyolysis and cardiotoxicity associated with the use of MDPHP. ED admissions were also more frequent in patients with addiction problems. In some cases, MDPHP intake required intensive supportive care. A multidisciplinary approach, including specialist consultation, is recommended for patients showing challenging features. Moreover, we demonstrated that the adoption of advanced analytical techniques, i.e., liquid chromatography-tandem mass spectrometry, is necessary to detect these molecules. Further studies are needed to understand MDPHP intake patterns and associated symptoms. It is essential to raise awareness in addiction treatment centers and among potential users, especially young people, and chemsex addicted.

Synthetic Cathinones: Epidemiology, Toxicity, Potential for Abuse, and Current Public Health Perspective

Synthetic cathinones, derived from cathinone found in the plant Catha edulis, represent the second largest and most frequently seized group of new psychoactive substances. They are considered as β-keto analogs of amphetamine, sharing pharmacological effects with amphetamine and cocaine. This review describes the neurotoxic properties of synthetic cathinones, encompassing their capacity to induce neuroinflammation, dysregulate neurotransmitter systems, and alter monoamine transporters and receptors. Additionally, it discusses the rewarding and abuse potential of synthetic cathinones drawing from findings obtained through various preclinical animal models, contextualized with other classical psychostimulants. The review also offers an overview of current abuse trends of synthetic cathinones on the illicit drug market, specifying the aspects covered, and underscores the risks they pose to public health. Finally, the review discusses public health initiatives and efforts to reduce the hazards of synthetic cathinones, including harm reduction methods, education, and current clinical management strategies.

PS2MS: A Deep Learning-Based Prediction System for Identifying New Psychoactive Substances Using Mass Spectrometry

The rapid proliferation of new psychoactive substances (NPS) poses significant challenges to conventional mass-spectrometry-based identification methods due to the absence of reference spectra for these emerging substances. This paper introduces PS2MS, an AI-powered predictive system designed specifically to address the limitations of identifying the emergence of unidentified novel illicit drugs. PS2MS builds a synthetic NPS database by enumerating feasible derivatives of known substances and uses deep learning to generate mass spectra and chemical fingerprints. When the mass spectrum of an analyte does not match any known reference, PS2MS simultaneously examines the chemical fingerprint and mass spectrum against the putative NPS database using integrated metrics to deduce possible identities. Experimental results affirm the effectiveness of PS2MS in identifying cathinone derivatives within real evidence specimens, signifying its potential for practical use in identifying emerging drugs of abuse for researchers and forensic experts.

Perioperative considerations for patients exposed to hallucinogens

Hallucinogen exposure in patients in the perioperative period presents challenges for anesthesiologists and other anesthesia providers. Acute and chronic exposure to these substances can cause physiological impacts that can affect the function of anesthetic and analgesic medications used during perioperative care. The objective of this narrative review is to educate readers on the wide array of hallucinogens and psychedelics that may influence the perioperative management of patients exposed to these substances. A narrative review of the literature surrounding hallucinogens and psychedelics was completed. Hallucinogens and psychedelics are quite varied in their mechanisms of action and therefore present a variety of perioperative implications and perioperative considerations. Many of these substances increase serotonin levels or act directly at serotonergic receptors. However, there are other relevant actions that may include varied mechanisms from N-methyl-D-aspartate receptor antagonism to stimulation of muscarinic receptors. With hallucinogen exposure rates on the rise, understanding the effects of hallucinogens is important for optimizing management and reducing risks perioperatively for patients with acute or chronic exposure.

α-Pyrrolidinononanophenone derivatives induce differentiated SH-SY5Y neuroblastoma cell apoptosis via reduction of antioxidant capacity: Involvement of NO depletion and inactivation of Nrf2/HO1 signaling pathway

α-Pyrrolidinononanophenone (α-PNP) derivatives are known to be one of the hazardous new psychoactive substances due to the most extended hydrocarbon chains of any pyrrolidinophenones on the illicit drug market. Our previous report showed that 4'-iodo-α-PNP (I-α-PNP) is the most potent cytotoxic compound among α-PNP derivatives and induces apoptosis due to mitochondrial dysfunction and suppression of nitric oxide (NO) production in differentiated human neuronal SH-SY5Y cells. In this study, to clarify the detailed action mechanisms by I-α-PNP, we investigated the mechanism of reactive oxygen species (ROS) -dependent apoptosis by I-α-PNP in differentiated SH-SY5Y with a focus on the antioxidant activities. Treatment with I-α-PNP elicits overproduction of ROS such as H2O2, hydroxyl radical, and 4-hydroxy-2-nonenal, and pretreatment with antioxidant N-acetyl-L-cysteine is attenuated the SH-SY5Y cells apoptosis by I-α-PNP. These results suggested that the overproduction of ROS is related to SH-SY5Y cell apoptosis by I-α-PNP. In addition, I-α-PNP markedly decreased antioxidant capacity in differentiated cells than in undifferentiated cells and inhibited the upregulation of hemeoxygenase 1 (HO1) and glutathione peroxidase 4 (GPX4) expression caused by induction of differentiation. Furthermore, the treatment with I-α-PNP increased the nuclear expression level of BTB Domain And CNC Homolog 1 (Bach1), a transcriptional repressor of Nrf2, only in differentiated cells, suggesting that the marked decrease in antioxidant capacity in differentiated cells was due to suppression of Nrf2/HO1 signaling by Bach1. Additionally, pretreatment with an NO donor suppresses the I-α-PNP-evoked ROS overproduction, HO1 down-regulation, increased nuclear Bach1 expression and reduced antioxidant activity in the differentiated cells. These findings suggest that the ROS-dependent apoptosis by I-α-PNP in differentiated cells is attributed to the inactivation of the Nrf2/HO1 signaling pathway triggered by NO depletion.

The pharmacology and neurotoxicology of synthetic cathinones

The synthetic cathinones are man-made compounds derived from the naturally occurring drug cathinone, which is found in the khat plant. The drugs in this pharmacological class that will be the focus of this chapter include mephedrone, MDPV, methcathinone and methylone. These drugs are colloquially known as "bath salts". This misnomer suggests that these drugs are used for health improvement or that they have legitimate medical uses. The synthetic cathinones are dangerous drugs with powerful pharmacological effects that include high abuse potential, hyperthermia and hyperlocomotion. These drugs also share many of the pharmacological effects of the amphetamine class of drugs including methamphetamine, amphetamine and MDMA and therefore have high potential to cause damage to the central nervous system. The synthetic cathinones are frequently taken in combination with other psychoactive drugs such as alcohol, marijuana and the amphetamine-like stimulants, creating a situation where heightened pharmacological and neurotoxicological effects are likely to occur. Despite the structural features shared by the synthetic cathinones and amphetamine-like stimulants, including their actions at monoamine transporters and receptors, the effects of the synthetic cathinones do not always match those of the amphetamines. In particular, the synthetic cathinones are far less neurotoxic than their amphetamine counterparts, they produce a weaker hyperthermia, and they cause less glial activation. This chapter will briefly review the pharmacology and neurotoxicology of selected synthetic cathinones with the aim of delineating key areas of agreement and disagreement in the literature particularly as it relates to neurotoxicological outcomes.

Interpretative problems due to the presence of chloromethcathinone isomers in the biological material from postmortem cases

While many new psychoactive substances often disappear from the drug market rather quickly, some, such as synthetic cathinones (SCs), still remain due to their popularity among users. The current knowledge of SC concentrations in blood samples is based mainly on the published case reports of intoxications or fatalities caused by SC intake. The aim of the present study was to present and interpret the obtained toxicological analysis results of these cases, in which it was possible to determine or detect the presence of one of the isomers of chloromethcathinone (CMC) along with its intake biomarker-dihydro-CMC. These cases include 27 deaths reported at the Department of Forensic Medicine in Kraków in 2016-2022. CMC constitutes a major toxicological opinion challenge, in terms of toxicological evaluation of poisonings. As presented in this paper, a significant problem is its stability in the biological material and practices in the reporting of the obtained data. It is therefore important to monitor potential intake biomarkers that may show greater stability in the biological material than the parent drug. In the case of CMC isomers, the good biomarker of intake is the dihydro-CMC metabolite, which was detected in the blood sample in every case presented, even with the absence of the parent substance. Interpretation of the results obtained for CMC in terms of assessing their toxicity and possible cause of death is difficult. However, it should be taken into account that in cases of new psychoactive substance poisoning, an in-depth risk assessment is mandatory and the opinion of the unpredictability of the effects is taken as a principle.

Oxidative Amination of Aldehydes with Amines into α-Amino Ketones

Oxidative amination for the installation of nitrogen functional molecules from nitrogen nucleophiles has always been a very challenging topic in organic synthesis. Here we report a novel conversion of different aldehydes with secondary amines for the synthesis of diversified α-amino ketones. This method can be achieved through oxidative rearrangement of an in situ-generated enamine intermediate promoted by commercially available sodium percarbonate. Furthermore, this one-pot process is also suitable for the functional modification of complex molecules.

Synergistic Multieffect Catalytic Amplified Cathodic Electrochemiluminescence Biosensor via Target Binding-Induced Aptamer Conformational Changes for the Ultrasensitive Detection of Synthetic Cathinone

Signal amplification is a powerful approach to increasing the detection sensitivity of electrochemiluminescence (ECL). Here, we developed synergistic multieffect catalytic strategies based on CuCo2O4 nanorod combination of Ag NPs as coreaction accelerators to fabricate an efficient covalent organic framework (PTCA-COF)-based ternary ECL biosensor. Concretely, the high redox reversibility of Co3+/Co2+ and Cu2+/Cu+ would constantly promote the decomposition of S2O82- for ECL emission. Meanwhile, the introduction of Ag NPs with excellent electrocatalytic activity further realized multiple amplification of the ECL signal. Furthermore, the good hydrogen evolution reaction (HER) ability of Ag@CuCo2O4 nanorods could accelerate the proton transmission rate of the system to amplify ECL behavior. In the presence of the target synthetic cathinone 4-chloroethcathinone (4-CEC) as the quenching ECL signal-response probe, the Ferrocene (Fc)-labeled aptamer folded into the conformationally limited stem-loop structure, bringing Fc near the ECL luminophore and resulting in quenched ECL emission. The quenching effect was connected with target-induced aptamer conformational changes and consequently reflected the target concentration. Under optimum conditions, the proposed biosensor realized a highly sensitive assay for 4-CEC with a large dynamic range from 1.0 × 10-12 to 1.0 × 10-6 g/L and a detection limit as low as 2.5 × 10-13 g/L. This study integrated multiple amplification strategies for efficient ECL enhancement, which provided a novel approach to constructing highly bioactive and sensitive sensors.

Electron activated dissociation - a complementary fragmentation technique to collision-induced dissociation for metabolite identification of synthetic cathinone positional isomers

Over the last decade, a remarkable number of new psychoactive substances (NPS) have emerged onto the drug market, resulting in serious threats to both public health and society. Despite their abundance and potential toxicity, there is little information available on their metabolism, a crucial piece of information for clinical and forensic purposes. NPS metabolism can be studied using in vitro models, such as liver microsomes, cytosol, hepatocytes, etc. The tentative structural elucidation of metabolites of NPS formed using in vitro models is typically carried out using liquid chromatography combined with high-resolution tandem mass spectrometry (LC-HRMS2) with collision-induced dissociation (CID) as a fragmentation method. However, the thermally-excited ions produced with CID may not be sufficient for unambiguous identification of metabolites or their complete characterization. Electron-activated dissociation (EAD), a relatively new fragmentation approach that can be used to fragment singly-charged ions, may provide complementary structural information that can be used to further improve the confidence in metabolite identification. The aim of this study was to compare CID and EAD as fragmentation methods for the characterization and identification of synthetic cathinone positional isomers and their metabolites. The in vitro metabolism of 2-methylethcathinone (2-MEC), 3-methylethcathinone (3-MEC) and 4-methylethcathinone (4-MEC) was investigated with both CID and EAD methods using LC-HRMS2. Four, seven and six metabolites were tentatively identified for the metabolism of 2-MEC, 3-MEC and 4-MEC, respectively. Here, the metabolism of 3-MEC and 2-MEC is reported for the first time. The EAD product ion mass spectra showed different fragmentation patterns compared to CID, where unique and abundant product ions were observed in EAD but not in CID. More importantly, certain EAD exclusive product ions play a significant role in structural elucidation of some metabolites. These results highlight the important role that EAD fragmentation can play in metabolite identification workflows, by providing additional fragmentation data compared with CID and, thus, enhancing the confidence in structural elucidation of drug metabolites.

Study on the degradation and pyrolysis of 2-fluoromethcathinone

Gas chromatography-mass spectrometry (GC-MS) is the first choice for law enforcement agencies in various countries to analyze new psychoactive substances (NPS) because of its advantages and complete databases. For synthetic cathinone-type NPS (SCat), alkalization and extraction processes before GC-MS analysis are essential. However, the base form of SCat is unstable, causing it to quickly degrade in solution and cause pyrolysis at the GC-MS injection inlet. In this study, we investigated the degradation of ethyl acetate and pyrolysis at the GC-MS injection inlet of 2-fluoromethcathinone (2-FMC), the most unstable SCat. Using gas chromatography-quadruple/time-of-flight mass spectrometry (GC-Q/TOF-MS) combined with the predicted data from theoretical calculations and the analysis of mass spectrometry (MS) fragmentation, the structures of 15 2-FMC degradation and pyrolysis products were identified. Among them, 11 products were produced during degradation, and six products were obtained from pyrolysis (two of which were the same as the degradation products). At the same time, the degradation and pyrolysis pathways of 2-FMC were provided. The balance between keto-enol and enamine-imine tautomerism triggered the primary degradation pathway of 2-FMC. The subsequent degradation started from the tautomer with a hydroxyimine structure, including imine hydrolysis, oxidation, imine-enamine tautomerism, intramolecular ammonolysis of halobenzene, and hydration to generate a series of degradation products. The secondary degradation reaction was the ammonolysis of ethyl acetate to yield N-[1-(2'-fluorophenyl)-1-oxopropan-2-yl]-N-methylacetamide and the byproduct, N-[1-(2'-fluorophenyl)-1-oxopropan-2-yl]-N-methylformamide. In the pyrolysis of 2-FMC, the major reactions were dehydrogenation, intramolecular ammonolysis of halobenzene, and defluoromethane. The achievements of this manuscript not only study 2-FMC degradation and pyrolysis but also lay the foundation for the study of SCat stability and their accurate analysis by GC-MS.

The Designer Drug αPHP Affected Cell Proliferation and Triggered Deathly Mechanisms in Murine Neural Stem/Progenitor Cells

Increasing reports of neurological and psychiatric outcomes due to psychostimulant synthetic cathinones (SCs) have recently raised public concern. However, the understanding of neurotoxic mechanisms is still lacking, particularly for the under-investigated αPHP, one of the major MDPV derivatives. In particular, its effects on neural stem/progenitor cell cultures (NSPCs) are still unexplored. Therefore, in the current in vitro study, the effects of increasing αPHP concentrations (25-2000 μM), on cell viability/proliferation, morphology/ultrastructure, genotoxicity and cell death pathways, have been evaluated after exposure in murine NSPCs, using a battery of complementary techniques, i.e., MTT and clonogenic assay, flow cytometry, immunocytochemistry, TEM, and patch clamp. We revealed that αPHP was able to induce a dose-dependent significant decrease of the viability, proliferation and clonal capability of the NSPCs, paralleled by the resting membrane potential depolarization and apoptotic/autophagic/necroptotic pathway activation. Moreover, ultrastructural alterations were clearly observed. Overall, our current findings demonstrate that αPHP, damaging NSPCs and the morpho-functional fundamental units of adult neurogenic niches may affect neurogenesis, possibly triggering long-lasting, irreversible CNS damage. The present investigation could pave the way for a broadened understanding of SCs toxicology, needed to establish an appropriate treatment for NPS and the potential consequences for public health.

Perioperative Considerations for Patients Exposed to Psychostimulants

Concerns regarding the perioperative management of acute psychostimulant intoxication have been recognized for decades, but novel and diverse substances in this class continue to be developed. Despite the similarities in mechanisms of action among psychostimulants, each subclass within this broad category has unique receptor specificity and different mechanisms that play a role in patient clinical presentation. These issues present challenges to anesthesia providers when caring for patients with either acute or chronic exposure to psychostimulants during the perioperative period. Challenges result from both physiological and psychological effects that influence the action of the primary anesthetic agent, adjuvant anesthetics, and analgesics used for perioperative management of pain. The epidemiology, pharmacology, and perioperative implications of psychostimulant use are presented for amphetamines and similar acting nonamphetamines, cocaine, and, finally, the mixed-action drugs known as entactogens that share stimulant and psychedelic properties. This information is then used as the foundation for safe and effective perioperative management of patients exposed to psychostimulants.

Drug regulations and trafficking: Synthetic cannabinoids and cathinones in Hungary

In principle, new psychoactive substances (NPSs) are produced to circumvent drug regulations. However, the mixed success of regulatory efforts suggests that the dynamics of marketing is incompletely understood. To address this issue, we conducted a comprehensive study on the marketing of all synthetic cannabinoids and cathinones present in Hungary over ten years. Market evaluation was based on drug seizure data and chemical analyses provided by the Hungarian Institute for Forensic Sciences. Over ten years, 18 synthetic cannabinoids and 11 cathinones were identified. Total seizure counts were 22,906 and 10,273, respectively. When new synthetic cannabinoids emerged, seizures increased exponentially, but rapidly declined after their banning. In parallel, new synthetic cannabinoids emerged on the market. The systematic monitoring of local legislation allowed large sales between market introduction and legal control. Cathinones were also marketed in successive waves, but trading intensity was not associated with local regulations. Sales remained low throughout, likely because the risks involved by the temporal mismatch between marketing and legal control. One can hypothesize that marketing was driven by general trends in EU regulations or by measures taken by large countries. Our findings imply the existence of two different strategies for NPS marketing. The choice between the two may depend on multiple factors from the availability of skills required by rapid marketing adjustments to cost/benefit evaluations for various market segments. Studying NPS market strategies in neighboring and distant EU countries may help analyzing and predicting market events.

Binding studies of synthetic cathinones to human serum albumin by high-performance affinity chromatography

The binding affinity to human serum albumin (HSA) of a series of fourteen synthetic cathinones, new psychoactive substances widely abused, was investigated by high-performance affinity chromatography (HPAC). Zonal elution experiments were conducted to measure the retention times of each synthetic cathinone on an HSA column, which enabled the calculation of the percentage of the drug bound. For some synthetic cathinones, enantioselectivity on HSA was found. To gather information on the HSA binding sites and better understand the chiral recognition mechanisms, enantioresolution of selected cathinones was carried out at a milligram scale through liquid chromatography (LC) with carbamate polysaccharide-based columns. This work was followed by zonal displacement chromatography using known competitors with specific binding sites on HSA, namely (S)-ibuprofen and warfarin. Competition was observed between the tested drugs and both competitors (except for pentedrone with warfarin), which is consistent with an allosteric competition involving a non-cooperative binding mechanism.

Acute, chronic, and post-mortem toxicity: a review focused on three different classes of new psychoactive substances

PURPOSE

New psychoactive substances (NPS) are not controlled under the Single Convention on Narcotic Drugs of 1961 or the 1971 Convention, but they may pose a public health threat. Knowledge of the main properties and toxicological effects of these substances is lacking. According to the current Drugs Law (Law n. 11.343/2006), the Brazilian Surveillance Agency issues directives for forbidden substances in Brazil, and structural classes of synthetic cannabinoids, cathinones, and phenylethylamines are considered illicit drugs. Considering that data on these controlled substances are scattered, the main objective of this work was to collect and organize data to generate relevant information on the toxicological properties of NPS.

METHODS

We carried out a literature review collecting information on the acute, chronic, and post-mortem toxicity of these classes of NSP. We searched info in five scientific databases considering works from 2017 to 2021 and performed a statistical evaluation of the data.

RESULTS

Results have shown a general lack of studies in this field given that many NPS have not had their toxicity evaluated. We observed a significant difference in the volume of data concerning acute and chronic/post-mortem toxicity. Moreover, studies on the adverse effects of polydrug use are scarce.

CONCLUSIONS

More in-depth information about the main threats involving NPS use are needed.

Neurochemical and Cardiovascular Effects of 4-Chloro Ring-Substituted Synthetic Cathinones in Rats

Synthetic cathinones are a class of new psychoactive substances that display psychomotor stimulant properties, and novel cathinone analogs continue to emerge in illicit drug markets worldwide. The aim of the present study was to characterize the pharmacology of 4-chloro ring-substituted cathinones that are appearing in illicit drug markets compared with the effects of 4-methylmethcathinone (mephedrone). Synaptosomes were prepared from rat caudate for dopamine transporter (DAT) assays or from whole brain minus caudate and cerebellum for norepinephrine transporter (NET) and serotonin transporter (SERT) assays. Findings from transporter uptake inhibition and release assays showed that mephedrone and 4-chloromethcathinone (4-CMC) function as substrates at DAT, NET, and SERT, with similar potency at all three transporters. In contrast, 4-chloro-α-pyrrolidinopropiophenone (4-CαPPP) was an uptake inhibitor at DAT and NET, with similar potency at each site, but had little activity at SERT. 4-Chloroethcathinone (4-CEC) was a low-potency uptake inhibitor at DAT and NET but a substrate at SERT. In rats implanted with telemetry transmitters, mephedrone and 4-CMC increased blood pressure, heart rate, and locomotor activity to a similar extent. 4-CEC and 4-CαPPP were less potent at increasing blood pressure and had modest stimulatory effects on heart rate and activity. 4-CMC also transiently decreased temperature at the highest dose tested. All three 4-chloro ring-substituted cathinones are biologically active, but only 4-CMC has potency comparable to mephedrone. Collectively, our findings suggest that 4-CMC and other 4-chloro cathinones may have abuse potential and adverse effects in humans that are analogous to those associated with mephedrone. SIGNIFICANCE STATEMENT: The 4-chloro ring-substituted cathinones all produced significant cardiovascular stimulation, with 4-chloromethcathinone (4-CMC) showing potency similar to mephedrone. All of the drugs are likely to be abused given their effects at the dopamine transporter, particularly 4-CMC.

Is There a Reduction in Chemsex Practice in Men Who Have Sex With Men During COVID-19 Lockdown? Results of the CheRRLock Study

BACKGROUND AND AIMS

Chemsex is a growing concern among men who have sex with men (MSM). COVID-19 lockdowns have had consequences on social and sexual interactions. We aimed to assess changes in chemsex practices during COVID-19 lockdown in France among MSM and factors associated with maintaining or increasing chemsex practice.

METHODS

Repeated face-to-face questionnaires were conducted at "Le 190" Sexual Health Center, Paris, France, exploring lifestyle, sexual, and chemsex practices, COVID-19 concerns and mental health before and during second lockdown in France (30/10/2020-15/12/2020). Inclusion criteria were chemsex practices at least 3 times throughout lifetime and at least once in the 3 months before second lockdown. The primary end point was the proportion of participants who declared having stopped, decreased, maintained, or increased their chemsex practice during lockdown. Univariable and multivariable logistic regressions were used to analyze factors associated with evolutions of chemsex practice.

RESULTS

Ninety-three MSM were included: 66% HIV-positive and 30% taking PrEP. Drugs most used were cathinones (91%) and GHB/GBL (52%). Participants reported stopping, decreasing, maintaining, and increasing chemsex drugs use in 14%, 22%, 22%, and 42% of cases, respectively. Despite this overall increase in chemsex practice, MSM decreased their number of sexual partners. Factors significantly associated with maintaining or increasing chemsex drugs use were feeling lonely (OR = 3.24), craving (OR = 4.51), and working during lockdown (OR = 3.27), contrasting with fear of COVID-19 (OR = 0.31).

CONCLUSION

Restriction measures lead to changes in sexual behavior and seem to increase chemsex practice. Maintaining care for most isolated patients should be a priority in COVID-19 context.

New Psychoactive Substances: A Potential Threat to Developing Countries

BACKGROUND

New psychoactive substances (NPS) have become a global phenomenon, with over 134 countries and territories from all world regions reporting them. Since December 2021, governments, laboratories, and partner agencies have confirmed to the UNODC Early Warning Advisory (EWA) on NPS over 1124 substances. It is agreed that NPS control is one of the most challenging tasks for developing countries. Identifying the present and future threads of NPS is the most challenging task for law enforcement officials. The NPS research has a great impact on substance abuse policy-making and harm reduction strategies.

METHODS

The data in this study were collected from the official websites of online journals, Google Scholar, UNODC, International Narcotics Control Board (INCB), and the Department of Narcotics Control (DNC).

FINDINGS

Among the eleven groups of NPS, synthetic cannabinoids and cathinones are the most prevalent and alarming in developing countries. In Bangladesh, NPS abuse has been first identified in 2016. Almost 60 countries adopted legislative solutions to manage NPS by 2021, with many using or amending existing legislation and others employing novel legal mechanisms. It is widely agreed by researchers that reducing the menace of NPS requires increased awareness among all stakeholders.

CONCLUSION

In the fight against the spread of NPS and its severe effects, law enforcement authorities and healthcare professional training must be seen as crucial aspects as well. Financing is also crucial for international organizations dealing with the NPS impact to continue fighting this war. The only way for policymakers to reduce NPS spread globally is through national and international cooperation.

Dual-binding domain electrochemiluminescence biosensing platform with self-checking function for sensitive detection of synthetic cathinone in e-cigarettes

Current single signal electrochemiluminescence (ECL) sensors are susceptible to false positive or false negative phenomena due to experimental conditions. Therefore, sensors with "self-checking" function are attracting democratic attention. In quick succession, a highly sensitive single-cathode dual ECL signal aptasensor with self-checking function to improve the shortcomings mentioned above was designed. This aptasensor used In-based metal-organic framework (MIL-68) as load and stabilizer to effectively attenuate the aggregation-induced quenching (ACQ) effect of porphyrin derivatives (Sn-TCPP) while improve ECL stability. The introduction of cooperative-binding split-aptamers" (CBSAs) aptamers increased the specificity of the aptasensor and its unique double-binding domains detection accelerated the detection efficiency. When analyzing 3,4-methylenedioxypyrovalerone (MDPV), we could calculate two concentrations based on the strength of ECL 1 and ECL 2. If the concentrations are the same, the result would be obtained; if not, it should be retested. Depending on the above operation, the results achieve self-check. It was found that the designed aptasensor could quantify the concentration of MDPV between 1.0 × 10^-12 g/L and 1.0 × 10^-6 g/L with the limit of detection (LOD) of 1.4 × 10^-13 g/L and 2.0 × 10^-13 g/L, respectively (3 σ/slope). This study not only improves the detection technology of MDPV, but also explores the dual-signal detection of porphyrin for the first time and enriches the definition of self-checking sensor.

Semi-Preparative Separation, Absolute Configuration, Stereochemical Stability and Effects on Human Neuronal Cells of MDPV Enantiomers

Synthetic cathinones, such as 3,4-methylenedioxypyrovalerone (MDPV), are widely abused due to their psychostimulant effects. As they are chiral molecules, studies of their stereochemical stability (racemization can occur in certain temperatures and acidic/basic environments) and of their biological and/or toxicity effects (enantiomers might display different properties) are of great relevance. In this study, the liquid chromatography (LC) semi-preparative enantioresolution of MDPV was optimized to collect both enantiomers with high recovery rates and enantiomeric ratio (e.r.) values. The absolute configuration of the MDPV enantiomers was determined by electronic circular dichroism (ECD) with the aid of theoretical calculations. The first eluted enantiomer was identified as S-(-)-MDPV and the second eluted enantiomer was identified as R-(+)-MDPV. A racemization study was performed by LC-UV, showing enantiomers' stability up to 48 h at room temperature and 24 h at 37 °C. Racemization was only affected by higher temperatures. The potential enantioselectivity of MDPV in cytotoxicity and in the expression of neuroplasticity-involved proteins-brain-derived neurotrophic factor (BDNF) and cyclin-dependent kinase 5 (Cdk5)-was also evaluated using SH-SY5Y neuroblastoma cells. No enantioselectivity was observed.

Structure-Activity Relationship of N-Ethyl-Hexedrone Analogues: Role of the α-Carbon Side-Chain Length in the Mechanism of Action, Cytotoxicity, and Behavioral Effects in Mice

Synthetic cathinones are β-keto amphetamine derivatives whose appearance has increased dramatically in the past decades. N-Ethyl substituted cathinones have been proven to potently inhibit dopamine (DA) uptake and induce psychostimulant and rewarding effects in mice. However, little is known about the influence of the alpha-carbon side-chain length of N-ethyl cathinones on their pharmacological and toxicological effects. Thus, the aim of this study was to synthesize and investigate the in vitro and in vivo effects of five N-ethyl substituted cathinones: N-ethyl-cathinone (NEC), N-ethyl-buphedrone (NEB), N-ethyl-pentedrone, N-ethyl-hexedrone (NEH), and N-ethyl-heptedrone. HEK293 cells expressing the human DA or serotonin transporter (hDAT and hSERT) were used for uptake inhibition and binding assays. PC12 cells were used for the cytotoxicity assays. Swiss CD-1 mice were used to study the in vivo psychostimulant, anxiogenic, and rewarding properties. Our results show that all tested cathinones are able to inhibit DA uptake and are DAT-selective. The potency of DA uptake inhibitors increases with the elongation of the aliphatic side chain from methyl to propyl and decreases when increasing from butyl to pentyl, which correlates with an inverted U-shape psychostimulant response in mice at the medium dose tested. On the other hand, an increase in the α-carbon side-chain length correlates with an increase in the cytotoxic properties in PC12 cells, probably due to better membrane penetration. Moreover, all the cathinones tested have shown higher cytotoxicity than methamphetamine. Finally, our study not only demonstrated the rewarding properties of NEC and NEB but also the anxiety-like behavior induced at high doses by all the cathinones tested.

New Psychoactive Substances: Major Groups, Laboratory Testing Challenges, Public Health Concerns, and Community-Based Solutions

Across communities worldwide, various new psychoactive substances (NPSs) continue to emerge, which worsens the challenges to global mental health, drug rules, and public health risks, as well as combats their usage. Specifically, the vast number of NPSs that are currently available, coupled with the rate at which new ones emerge worldwide, increasingly challenges both forensic and clinical testing strategies. The well-established NPS detection techniques include immunoassays, colorimetric tests, mass spectrometric techniques, chromatographic techniques, and hyphenated types. Nonetheless, mitigating drug abuse and NPS usage is achievable through extensive community-based initiatives, with increased focus on harm reduction. Clinically validated and reliable testing of NPS from human samples, along with community-driven solution, such as harm reduction, will be of great importance, especially in combating their prevalence and the use of other illicit synthetic substances. There is a need for continued literature synthesis to reiterate the importance of NPS, given the continuous emergence of illicit substances in the recent years. All these are discussed in this overview, as we performed another look into NPS, from differentiating the major groups and identifying with laboratory testing challenges to community-based initiatives.

Synthesis of emerging cathinones and validation of a SPE GC-MS method for their simultaneous quantification in blood

Over the past 15 years, synthetic cathinones have emerged as an important class of new psychoactive substances (NPS) worldwide. The proliferation of these psychostimulants and their sought-after effects among recreational drug users pose a serious threat to public health and enormous challenges to forensic laboratories. For forensic institutions, it is essential to be one step ahead of covert laboratories, foreseeing the structural changes possible to introduce in the core skeleton of cathinones while maintaining their stimulating activity. In this manner, it is feasible to equip themselves with standards of possible new cathinones and validated analytical methods for their qualitative and quantitative detection. Therefore, the aim of the work herein described was to synthesize emerging cathinones based on the evolving patterns in the illicit drug market, and to develop an analytical method for their accurate determination in forensic situations. Five so far unreported cathinones [4'-methyl-N-dimethylbuphedrone (4-MDMB), 4'-methyl-N-ethylbuphedrone (4-MNEB), 4'-methyl-N-dimethylpentedrone (4-MDMP), 4'-methyl-N-dimethylhexedrone (4-MDMH), and 4'-methyl-N-diethylbuphedrone (4-MDEB)] and a sixth one, 4'-methyl-N-ethylpentedrone, already reported to EMCDDA and also known as 4-MEAP, were synthesized and fully characterized by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). An analytical method for the simultaneous quantification of these cathinones in blood, using solid phase extraction (SPE) combined with gas chromatography-mass spectrometry (GC-MS) was developed and validated. The results prove that this methodology is selective, linear, precise, and accurate. For all target cathinones, the extraction efficiency was higher than 73%, linearity was observed in the range of 10 (lower limit of quantification, LLOQ) to 800 ng/mL, with coefficients of determination higher than 0.99, and the limits of detection (LODs) were 5 ng/mL for all target cathinones. The stability of these cathinones in blood matrices is dependent on the storage conditions; 4-MNEB is the most stable compound and 4-MDMH is the least stable compound. The low limits obtained allow the detection of the compounds in situations where they are involved, even if present at low concentrations.

Assessment of the Permeability of 3,4-Methylenedioxypyrovalerone (MDPV) across the Caco-2 Monolayer for Estimation of Intestinal Absorption and Enantioselectivity

3,4-Methylenedioxypyrovalerone (MDPV) is a widely studied synthetic cathinone heterocycle mainly concerning its psychoactive effects. It is a chiral molecule and one of the most abused new psychoactive substances worldwide. Enantioselectivity studies for MDPV are still scarce and the extent to which it crosses the intestinal membrane is still unknown. Herein, an in vitro permeability study was performed to evaluate the passage of the enantiomers of MDPV across the Caco-2 monolayer. To detect and quantify MDPV, a UHPLC-UV method was developed and validated. Acceptable values within the recommended limits were obtained for all evaluated parameters (specificity, linearity, accuracy, limit of detection (LOD), limit of quantification (LOQ) and precision). The enantiomers of MDPV were found to be highly permeable across the Caco-2 monolayer, which can indicate a high intestinal permeability. Enantioselectivity was observed for the P_app values in the basolateral (BL) to apical (AP) direction. Furthermore, efflux ratios are indicative of efflux through a facilitated diffusion mechanism. To the best of our knowledge, determination of the permeability of MDPV across the intestinal epithelial cell monolayer is presented here for the first time.

Synthetic Cathinones in Belgium: Two Case Reports with Different Outcomes Observed in the Emergency Room

We herein report two cases of cathinone intoxication. The first case is about a drug addict who was admitted to the emergency room after the injection of an unknown compound. He presented with tachycardia, palpitations, mydriasis, dyspnea, dizziness, headache and nausea. After leaving the hospital against medical advice, he returned the next day with police escort, presenting aggressiveness and agitation signs. One month later, he returned one more time for sleeping disorders, hallucinations and anxiety. He was finally transferred for his 21st detoxification treatment. The second case concerns a man who was wandering the streets and tried to escape when police officers called him. He confessed to snorting of N-ethylpentedrone and was admitted with severe agitation including delusion of persecution, tachycardia, mydriasis and fever. Because of renal failure, rhabdomyolysis and metabolic acidosis, he was transferred to the intensive care unit where he manifested worsening of the symptoms, turning into coma. He was intubated for 3 days before a complete resolution of the symptoms. A screening was performed by high-resolution mass spectrometry followed by quantifications made by high-performance liquid chromatography coupled with a diode array detector. In the first case, alpha-pyrrolidinohexiophenone was identified only during the first two admissions. However, as plenty of other psychotropic substances were also found, the cathinone alone could not be held directly responsible for the symptoms. In the second case, more than 2,000 ng/mL of N-ethylpentedrone was found without any decrease in the next 17 h, underlining the long half-life of this compound. Unlike the first case, symptoms could be clearly attributed to the cathinone. In conclusion, cathinones can be found on the Belgian illicit drug market, with various routes of administration and clinical consequences. In these two case reports, some common points were observed initially. However, one patient was finally able to leave the hospital without any treatment, whereas the other would most likely have died without intensive care.

Pharmaco-Toxicological Effects of Atypical Synthetic Cathinone Mephtetramine (MTTA) in Mice: Possible Reasons for Its Brief Appearance over NPSs Scene

Over the last year, NPSs have been steadily on the rise in the illicit drug market. Among these, synthetic cathinones seem to become increasingly popular among young adults, mainly because of their ability to replicate the effects of traditional psychostimulant drugs, such as cocaine, MDMA and amphetamines. However, scarce data are available about the in vivo pharmaco-toxicology of these new substances. To this end, this study focused on evaluation of effects induced by repeated administration of mephtetramine (MTTA 0.1-30 mg/kg i.p.) in mice. This atypical cathinone highlighted a sensorial (inhibition of visual and acoustic reflexes) and transient physiological parameter (decrease in breath rate and temperature) change in mice. Regarding motor activity, both a dose-dependent increase (accelerod test) and biphasic effect (drag and mobility time test) have been shown. In addition, blood and urine samples have been analysed to enrich the experimental featuring of the present study with reference to evaluation of potential toxicity related to consumption of MTTA. The latter analysis has particularly revealed important changes in blood cells count and blood and urine physicochemical profile after repeated treatment with this atypical cathinone. Moreover, MTTA induced histological changes in heart, kidney and liver samples, emphasizing its potential toxicity.

Defective determination of synthetic cathinones in blood for forensic investigation

Antemortem specimens are sometimes the sole sources available for forensic investigation, and samples collected in nonideal ways are inevitably employed to achieve toxicological analysis. It is essential to assess the effects of blood collection tubes on the recoveries of emerging synthetic cathinones (SC) to estimate actual drug concentrations, and no such systematic investigations have been previously carried out. Seventy-one SC with various LogP values were employed to examine commonly used blood collection tubes, including plasma tubes, serum tubes and gel-containing tubes in recoveries which determined by a reliable LC-MS/MS method. Significantly poor recoveries for hydrophobic SC were obtained using serum separating tubes (SST). Notably, the suppressed recoveries in SST can be reversed by adding anticoagulants. Adding a procoagulant to a plasma separating tube (PST) considerably reduced recoveries, which indicated that clotting processes in the presence of polymeric gels contributed to poor recoveries of these hydrophobic drugs. In this study, we find that clotting formation in the presence of polymeric gels could significantly affect the determination of hydrophobic drugs. However, in real-world scenarios, nonideal collection methods are inevitably employed for antemortem specimens. Thus, it is important to rigorously interpret forensic toxicological results, especially for susceptible species.

Identification and analytical characterization of N-propyl norbutylone, N-butyl norbutylone, N-benzyl norheptedrone, and N-pyrrolidinyl-3,4-DMA

In this study, the analytical characterization of three cathinones and one N-pyrrolidinyl-substituted amphetamine derivative is described: 1-([3,4-methylenedioxyphenyl])-2-(propylamino)butan-1-one (N-propyl norbutylone 1), 1-([3,4-methylenedioxyphenyl])-2-(butylamino)butan-1-one (N-butyl norbutylone 2), 2-(benzylamino)-1-phenylheptan-1-one (N-benzyl norheptedrone 3), and 1-(1-[3,4-dimethoxyphenyl]propan-2-yl)pyrrolidine (N-pyrrolidinyl-3,4-DMA 4). The identification was based on ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UHPLC-QTOF-MS), gas chromatography-orbitrap MS (GC-Orbitrap-MS), nuclear magnetic resonance spectroscopy (NMR), and Fourier transform infrared (FT-IR). GC-Orbitrap-MS, with higher mass accuracy, benefit more on the accurate structure elucidation of product ions compared with the low-resolution GC-MS. The collision-induced dissociation (CID) and electron ionization (EI) pathways of these compounds were examined to assist forensic laboratories in elucidating the structure of new psychoactive substances (NPS) with similar structure in their case work. In addition, electron activated dissociation (EAD) was applied to analyze N-benzyl norheptedrone, which showed only one product ion in the CID mode. The result showed that for compound with limited product ions in the CID mode, the EAD mode can give more complementary information for structure elucidation. In addition, quantitative NMR (qNMR) was applied for the quantification of four powdered/crystal and two herbal blend seized samples. To our knowledge, no analytical data about the compounds 3 and 4 have appeared until now, making this the first report on these compounds.

A review of synthetic cathinones emerging in recent years (2019-2022)

Purpose

The emergence of novel psychoactive substances (NPS) has been being a continuous and evolving problem for more than a decade. Every year, dozens of new, previously unknown drugs appear on the illegal market, posing a significant threat to the health and lives of their users. Synthetic cathinones are one of the most numerous and widespread groups among NPS. The purpose of this work was to identify and summarize available data on newly emerging cathinones in very recent years.

Methods

Various online databases such as PubMed, Google Scholar, but also databases of government agencies including those involved in early warning systems, were used in search of reports on the identification of newly emerging synthetic cathinones. In addition, threads on various forums created by users of these drugs were searched for reports on the effects of these new substances.

Results

We have identified 29 synthetic cathinones that have been detected for the first time from early 2019 to mid-2022. We described their structures, known intoxication symptoms, detected concentrations in biological material in poisoning cases, as well as the countries and dates of their first appearance. Due to the lack of studies on the properties of the novel compounds, we compared data on the pharmacological profiles of the better-known synthetic cathinones with available information on the newly emerged ones. Some of these new agents already posed a threat, as the first cases of poisonings, including fatal ones, have been reported.

Conclusions

Most of the newly developed synthetic cathinones can be seen as analogs and replacements for once-popular compounds that have been declining in popularity as a result of legislative efforts. Although it appears that some of the newly emerging cathinones are not widely used, they may become more popular in the future and could become a significant threat to health and life. Therefore, it is important to continue developing early warning systems and identifying new compounds so that their widespread can be prevented.

In Vitro and In Vivo Toxicometabolomics of the Synthetic Cathinone PCYP Studied by Means of LC-HRMS/MS

Synthetic cathinones are one important group amongst new psychoactive substances (NPS) and limited information is available regarding their toxicokinetics and -dynamics. Over the past few years, nontargeted toxicometabolomics has been increasingly used to study compound-related effects of NPS to identify important exogenous and endogenous biomarkers. In this study, the effects of the synthetic cathinone PCYP (2-cyclohexyl-1-phenyl-2-(1-pyrrolidinyl)-ethanone) on in vitro and in vivo metabolomes were investigated. Pooled human-liver microsomes and blood and urine of male Wistar rats were used to generate in vitro and in vivo data, respectively. Samples were analyzed by liquid chromatography and high-resolution mass spectrometry using an untargeted metabolomics workflow. Statistical evaluation was performed using univariate and multivariate statistics. In total, sixteen phase I and one phase II metabolite of PCYP could be identified as exogenous biomarkers. Five endogenous biomarkers (e.g., adenosine and metabolites of tryptophan metabolism) related to PCYP intake could be identified in rat samples. The present data on the exogenous biomarker of PCYP are crucial for setting up analytical screening procedures. The data on the endogenous biomarker are important for further studies to better understand the physiological changes associated with cathinone abuse but may also serve in the future as additional markers for an intake.

Natural Sympathomimetic Drugs: From Pharmacology to Toxicology

Sympathomimetic agents are a group of chemical compounds that are able to activate the sympathetic nervous system either directly via adrenergic receptors or indirectly by increasing endogenous catecholamine levels or mimicking their intracellular signaling pathways. Compounds from this group, both used therapeutically or abused, comprise endogenous catecholamines (such as adrenaline and noradrenaline), synthetic amines (e.g., isoproterenol and dobutamine), trace amines (e.g., tyramine, tryptamine, histamine and octopamine), illicit drugs (e.g., ephedrine, cathinone, and cocaine), or even caffeine and synephrine. In addition to the effects triggered by stimulation of the sympathetic system, the discovery of trace amine associated receptors (TAARs) in humans brought new insights about their sympathomimetic pharmacology and toxicology. Although synthetic sympathomimetic agents are mostly seen as toxic, natural sympathomimetic agents are considered more complacently in the terms of safety in the vision of the lay public. Here, we aim to discuss the pharmacological and mainly toxicological aspects related to sympathomimetic natural agents, in particular of trace amines, compounds derived from plants like ephedra and khat, and finally cocaine. The main purpose of this review is to give a scientific and updated view of those agents and serve as a reminder on the safety issues of natural sympathomimetic agents most used in the community.

Methylone and MDMA Pharmacokinetics Following Controlled Administration in Humans

The aim of this study is to define, for the first time, human methylone and HMMC plasma pharmacokinetics following controlled administration of 50-200 mg methylone to 12 male volunteers. A new LC-MS/MS method was validated to quantify methylone, MDMA, and their metabolites in plasma. The study was a randomized, cross-over, double-blinded and placebo-controlled study, with a total of 468 plasma samples collected. First, 10 µL of MDMA-d₅, MDA-d₅ and methylone-d₃ internal standards were added to 100 µL of plasma. Two mL of chloroform and ethyl acetate 9:1 (v/v) were then added, mixed well and centrifuged. The supernatant was fortified with 0.1 mL acidified methanol and evaporated under nitrogen. Samples were reconstituted with a mobile phase and injected into the LC-MS/MS instrument. The method was fully validated according to OSAC guidelines (USA). Methylone plasma concentrations increased in a dose-proportional manner, as demonstrated by the increasing maximum concentration (Cmax) and area under the curve of concentrations (AUC). Methylone Cmax values were reported as 153, 304, 355 and 604 ng/mL, AUC0-24 values were reported as 1042.8, 2441.2, 3524.4 and 5067.9 h·ng/mL and T_1/2 values as 5.8, 6.4, 6.9 and 6.4 h following the 50, 100, 150 and 200 mg doses, respectively. Methylone exhibited rapid kinetics with a Tmax of 1.5 h for the 50 mg dose and 2 h approximately after all the other doses. HMMC exhibited faster kinetics compared to methylone, with a Cmax value that was 10-14-fold lower and an AUC0-24 value that was 21-29-fold lower. Methylone pharmacokinetics was linear across 50-200 mg oral doses in humans, unlike the previously described non-linear oral MDMA pharmacokinetics. An LC-MS/MS method for the quantification of methylone, MDMA and their metabolites in human plasma was achieved. Methylone exhibited linear pharmacokinetics in humans with oral doses of 50-200 mg.

Relative reinforcing effects of dibutylone, ethylone, and N-ethylpentylone: self-administration and behavioral economics analysis in rats

RATIONALE

Following the emergence of methylone as one of the most popular synthetic cathinones, this group of novel psychoactive substance with names ending in "-lone," such as dibutylone, ethylone, and N-ethylpentylone, appeared on the recreational drug market. The pharmacological mechanisms of dibutylone, ethylone, and N-ethylpentylone are well understood; however, to date, the reinforcing effects of dibutylone, ethylone, and N-ethylpentylone are still unclear.

OBJECTIVES

This study aimed to examine the self-administration of dibutylone, ethylone, and N-ethylpentylone relative to methamphetamine (METH) and to quantify their relative reinforcing effectiveness using behavioral economic analysis.

METHODS

Male Sprague-Dawley rats were trained to self-administer METH (0.05 mg/kg) under a fixed-ratio 1 (FR1) schedule. Following the training, dose substitution was used to generate full dose-response curves for METH and the three synthetic cathinones. According to the first doses on the descending limb of the dose-response curves, rats were trained to self-administer METH (0.05 mg/kg), dibutylone (0.1 mg·kg^-1·infusion^-1), ethylone (0.4 mg·kg^-1·infusion^-1), or N-ethylpentylone (0.1 mg·kg^-1·infusion^-1) under an FR1 schedule, and a behavioral economic evaluation of their reinforcing effectiveness was then performed.

RESULTS

Dibutylone, ethylone, and N-ethylpentylone functioned as reinforcers, and the inverted U-shaped dose-response curves were obtained. The rank order of reinforcing potency in this procedure was METH > N-ethylpentylone ≈ dibutylone > ethylone. In the economic analysis, the comparisons of the essential value (EV) transformed from demand elasticity (α) indicated that the rank order of efficacy as reinforcers was METH (EV = 7.93) ≈ dibutylone (EV = 7.81) > N-ethylpentylone (EV = 5.21) ≈ ethylone (EV = 4.19).

CONCLUSIONS

These findings demonstrated that dibutylone, ethylone, and N-ethylpentylone function as reinforcers and have addictive potential, suggesting that the modification of α-alkyl and N-alkyl side chains may affect their reinforcing efficacy.

Liquid chromatography-tandem mass spectrometry method for simultaneous quantification of neurotransmitters in rat brain tissue exposed to 4'-Fluoro-α-PHP

The combination of different advanced analytical techniques makes it possible to determine the concentrations of neurotransmitters in various biological matrices, providing a complex and comprehensive study of the effects of psychoactive substances. The present study aimed to develop and validate a fast and simple analytical method for the determination of acetylcholine, serotonin, γ-aminobutyric acid, glutamate, dopamine, and metabolites in rats brain tissue by liquid chromatography coupled to tandem mass spectrometry. The brain was homogenized and an aliquot of sample, dopamine-d₄ , and acetone were added in a tube and then vortexed and centrifuged. The supernatant was collected and dried. The residue was reconstituted and injected. LLOQ ranged from 0.001 to 1 μg/g; intra-run precision from 0.47 to 11.52%; inter-run precision from 0.68 to 17.54%; bias from 89.10 to 109.60%. As proof of concept, the method was applied to animals exposed to the synthetic cathinone 4'-fuoro-α-pyrrolidinohexanophenone (300 mg/kg). In addition, the workflow proved to be simple, rapid, and useful to estimate the concentration of neurotransmitters. This analytical tool can be used to support the investigation of the changes in the neurochemical profile for the characterization of the mechanism of action of psychoactive substances, as well as both neurologic and psychiatric diseases.

4'-Iodo-α-Pyrrolidinononanophenone Provokes Differentiated SH-SY5Y Cell Apoptosis Through Downregulating Nitric Oxide Production and Bcl-2 Expression

Abuse of pyrrolidinophenone derivatives (PPs) is known to cause severe damage to the central nervous system due to their high lipophilicity. In this study, we compared sensitivity to toxicity elicited by 4'-iodo-α-pyrrolidinononanophenone (I-α-PNP), one of the most potent cytotoxic derivatives among PPs synthesized previously, between SH-SY5Y cells differentiated by all-trans-retinoic acid (ATRA) and the undifferentiated cells, and found that the differentiated cells are more sensitive to I-α-PNP toxicity than the undifferentiated cells. Treatment with I-α-PNP elicited some apoptotic alterations (Bax expression, loss of mitrochondrial membrane potential, and activation of caspases) in the differentiated cells, whose patterns were similar to those in the undifferentiated cells. I-α-PNP treatment resulted in no significant alteration in Bcl-2 expression in the undifferentiated cells, whereas it considerably downregulated the protein expression in the differentiated cells, suggesting that the high I-α-PNP sensitivity of the differentiated cells is mainly due to downregulation of Bcl-2 expression. I-α-PNP treatment decreased nitric oxide (NO) production and neuronal NOS (nNOS) expression in the differentiated cells, and the patterns of I-α-PNP-evoked alterations in phosphorylation of cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) expression were almost the same as that in nNOS expression. Additionally, the addition of an NO donor restored the I-α-PNP-evoked alterations in expressions of Bcl-2, BDNF, and nNOS in the differentiated cells. These findings suggest that the downregulation of Bcl-2 expression by I-α-PNP in differentiated cells is attributed to the acceleration of two negative feedback loops (nNOS/NO/CREB loop and CREB/BDNF loop) triggered by decreased NO production.

Fluorescent lanthanide metal-organic framework for rapid and ultrasensitive detection of methcathinone in human urine

Methcathinone (MC), a new and easily abused psychoactive substance, not only has a rigorous impact on public security, but also endangers people's health. Herein, novel fluorescent europium metal-organic frameworks (Eu-MOF) were synthesized through a facile one-step solvothermal strategy and utilized as an effective "signal-off" sensing platform for rapid and ultrasensitive detection of MC. The as-fabricated Eu-MOF possessed superior optical properties encompassing bright red fluorescence and good photostability. In the presence of MC, the fluorescence of Eu-MOF was significantly quenched, mainly attributing to the internal filtering effect between Eu-MOF and MC. The fluorescent signal showed high selectivity for MC over other illicit drugs, and offered two linear ranges of 1-100 ng/mL and 100-4000 ng/mL with a detection limit of 0.40 ng/mL. Strikingly, the nanoprobe could be applied for the assay of MC in human urine with satisfactory recoveries and acceptable results. This work provides a promising route for MC detection to effectively control illicit drug pandemic worldwide.

Comparison of clinical characteristics between meth/amphetamine and synthetic cathinone users presented to the emergency department

BACKGROUND

Synthetic cathinones (SC) are popular new psychoactive substances that produce sympathomimetic toxicity. Meth/amphetamine and SC have similar chemical structures and pharmacological effects. We aimed to compare the clinical characteristics between meth/amphetamine and SC users presenting to the emergency department (ED).

METHODS

This retrospective observational cohort study included patients who presented to six EDs from May 2017 to April 2021 with symptoms that related to recreational drug use and whose urine toxicology tests were positive only for meth/amphetamine or SC through liquid chromatography-tandem mass spectrometry.

RESULTS

There were 379 patients who tested positive only for meth/amphetamine (MA group), and 87 patients tested positive only for SC (SC groups). Patients in the MA group were older than those in the SC group (median (IQR); MA: 37.0 (30-43.7), SC: 25.0 (21.0-32.7), p < 0.001). There were no significant between-group differences in the sex distribution and initial chief complaints. Compared with the MA group, the SC group had more cases of tachycardia (≥ 135/min; MA: 29 (8.2%), SC:16 (19.0%), p = 0.0031) and hyperthermia (≥ 38 °C; MA: 31 (8.2%), SC:18 (20.7%), p = 0.001). Besides, the SC group had significantly higher levels of creatinine kinase (CK, IU/L; MA: 263 (115-601), SC: 497 (206-9216), p = 0.008) as well as a higher risk of rhabdomyolysis (CK > 1000; MA:32 (8.4%), SC: 16 (18.4%), p = 0.006) and severe rhabdomyolysis (CK > 10,000; MA:10 (2.6%), SC:10 (11.5%), p = 001). Multivariable logistic regression analyses indicated SC group in comparison with the MA group (adjusted odds ratio: 2.732, 95% confidence interval: 1. 250-5.972, p = 0.012) was an association with the risk of rhabdomyolysis.

CONCLUSION

Our findings demonstrate that tachycardia, hyperthermia, and rhabdomyolysis were more common among cathinone users than among meth/amphetamine users presented to EDs.

An Update on the Implications of New Psychoactive Substances in Public Health

The emergence of new psychoactive substances has earned a great deal of attention, and several reports of acute poisoning and deaths have been issued involving, for instance, synthetic opiates. In recent years, there have been profound alterations in the legislation concerning consumption, marketing, and synthesis of these compounds; rapid alert systems have also been subject to changes, and new substances and new markets, mainly through the internet, have appeared. Their effects and how they originate in consumers are still mostly unknown, primarily in what concerns chronic toxicity. This review intends to provide a detailed description of these substances from the point of view of consumption, toxicokinetics, and health consequences, including case reports on intoxications in order to help researchers and public health agents working daily in this area.

Synthetic Cathinones: Recent Developments, Enantioselectivity Studies and Enantioseparation Methods

New psychoactive substances represent a public health threat since they are not controlled by international conventions, are easily accessible online and are sold as a legal alternative to illicit drugs. Among them, synthetic cathinones are widely abused due to their stimulant and hallucinogenic effects. To circumvent the law, new derivatives are clandestinely synthesized and, therefore, synthetic cathinones keep emerging on the drug market, with their chemical and toxicological properties still unknown. In this review, a literature assessment about synthetic cathinones is presented focusing on the recent developments, which include more than 50 derivatives since 2014. A summary of their toxicokinetic and toxicodynamic properties are also presented. Furthermore, synthetic cathinones are chiral compounds, meaning that they can exist as two enantiomeric forms which may present different biological and toxicological activities. To analyze the enantiomers, the development of enantiomeric resolution methods for synthetic cathinones is crucial. Many methods have been reported over the years that include mostly chromatographic and electromigration techniques, with liquid chromatography using chiral stationary phases being the technique of choice. This review intended to present an overview of enantioselectivity studies and enantioseparation analysis regarding synthetic cathinones, highlighting the relevance of chirality and current trends.

Akathisia after chronic usage of synthetic cathinones: A case study

INTRODUCTION

Synthetic cathinones are a heterogenous group of new psychoactive substances (NPS) with a surging prevalence of use. They are sold under the name of "Bath Salts," "Legal Highs" or "Research Chemical." It is a heterogeneous group of substances that have a varying binding selectivity and affinity. Due to limited availability of NPS screening tests, inadequate legislation, the exponential increases in availability of new NPS and the comorbid use of other illicit substances, scientific research remains scarce. As a result, insight in their mental and psychomotor effects is limited.

CASE DESCRIPTION

We present a case of a 21-year-old woman with daily usage of synthetic cathinones, more specifically α-Pyrrolidinopentiophenone (α-PVP-better known as "Flakka"), α-Pyrrolidinohexiophenone (α-PHP) and alpha-Pyrrolidinoisohexaphenone (α-PHiP). Besides a severe paranoid psychotic state of mind, characterized by persecutory and somatic delusions, there was also a very pronounced psychomotor restlessness during the whole period of hospitalization which was diagnosed as akathisia. She reported that she was unable to sit during meals, had difficulty standing still and felt a constant urge to pay attention to the restlessness. The patient did not take any antipsychotic medication at admission.

RESULTS

The patient was treated in accordance with the current guidelines concerning akathisia with a combination of Quetiapine 200 mg, Propranolol 80 mg, Diazepam 10 mg, Biperiden 4 mg, and Mirtazapine 15 mg without any sufficient alleviation of complaints. Before the start of the treatment, Barnes Akathisia Rating Scale (BARS) score was 11 out of 14 which evolved toward a score of 7 over the course of the 40 day hospitalization, implying persisting severe akathisia which only improved modestly.

CONCLUSION

The current case suggests that besides cocaine, amphetamines and methamphetamines, synthetic cathinones can also increase the risk for development of extrapyramidal symptoms such as akathisia. Especially a-PVP-analogs as used by the current patient and Pyrovalerone-analogs such as Methylenedioxypyrovalerone (MDPV) are very powerful dopamine reuptake-inhibitors which might lead to strong locomotor activation. Up to this day it remains very difficult to establish a guideline concerning the treatment of intoxication with synthetic cathinones or dependence thereof.