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Nadal-Gratacós N, Pazos MD, Pubill D, Camarasa J, Escubedo E, Berzosa X, López-Arnau R. Structure-Activity Relationship of Synthetic Cathinones: An Updated Review. ACS Pharmacol Transl Sci 2024; 7:2588-2603. [PMID: 39296271 PMCID: PMC11406692 DOI: 10.1021/acsptsci.4c00299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/10/2024] [Accepted: 07/15/2024] [Indexed: 09/21/2024]
Abstract
The escalating prevalence of new psychoactive substances (NPSs) poses a significant public health challenge, evidenced by the vast chemical diversity, with over 500 substances reported annually to the United Nations Office on Drugs and Crime-Early Warning Advisory (UNODC-EWA) in the past five years. Among NPSs, synthetic cathinones are gaining a lot of popularity among users. Notably, synthetic cathinones accounted for approximately 50% of the total quantity of NPSs reported as seized by EU Member States in 2021. Preliminary data from UNODC indicates that a total of 209 synthetic cathinones have been reported to date. As their popularity grows, studying the structure-activity relationship (SAR) of synthetic cathinones is essential. SAR studies elucidate how structural features impact biological effects, aiding in toxicity prediction, regulatory compliance, and forensic identification. Additionally, SAR studies play a pivotal role in guiding drug policies, aiding authorities in categorizing and regulating newly emerging synthetic cathinones, mitigate public health risks and offer valuable insights into potential therapeutic applications. Thus, our Review consolidates recent findings on the effects of different substitutions in the chemical scaffold of synthetic cathinones on their mechanism of action as well as pharmacological and toxicological effects of synthetic cathinones, thus enhancing understanding of the SAR of synthetic cathinones' pharmacology and potential implications.
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Affiliation(s)
- Núria Nadal-Gratacós
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Pharmacology Section and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
- Chemical Reactions for Innovative Solutions (CRISOL), IQS School of Engineering, Universitat Ramon Llull, 08017 Barcelona, Spain
| | - Martalu D Pazos
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Pharmacology Section and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
| | - David Pubill
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Pharmacology Section and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
| | - Jorge Camarasa
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Pharmacology Section and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
| | - Elena Escubedo
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Pharmacology Section and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
| | - Xavier Berzosa
- Chemical Reactions for Innovative Solutions (CRISOL), IQS School of Engineering, Universitat Ramon Llull, 08017 Barcelona, Spain
| | - Raúl López-Arnau
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Pharmacology Section and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
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Nguyen VT, Harris AC, Eltit JM. Structural and functional perspectives on interactions between synthetic cathinones and monoamine transporters. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2023; 99:83-124. [PMID: 38467490 DOI: 10.1016/bs.apha.2023.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Synthetic cathinone derivatives comprise a family of psychoactive compounds structurally related to amphetamine. Over the last decade, clandestine chemists have synthesized a consistent stream of innovative cathinone derivatives to outpace governmental regulatory restrictions. Many of these unregulated substances are produced and distributed as designer drugs. Two of the principal chemical scaffolds exploited to expand the synthetic cathinone family are methcathinone and α-pyrrolidinopentiophenone (or α-pyrrolidinovalerophenone, α-PVP). These compounds' main physiological targets are monoamine transporters, where they promote addiction by potentiating dopaminergic neurotransmission. This chapter describes techniques used to study the pharmacodynamic properties of cathinones at monoamine transporters in vitro. Biochemical techniques described include uptake inhibition and release assays in rat brain synaptosomes and in mammalian expression systems. Electrophysiological techniques include current measurements using the voltage clamp technique. We describe a Ca2+ mobilization assay wherein voltage-gated Ca2+ channels function as reporters to study the action of synthetic cathinones at monoamine transporters. We discuss results from systematic structure-activity relationship studies on simple and complex cathinones at monoamine transporters with an emphasis on identifying structural moieties that modulate potency and selectivity at these transporters. Moreover, different profiles of selectivity at monoamine transporters directly predict compounds associated with behavioral and subjective effects within animals and humans. In conclusion, clarification of the structural aspects of compounds which modulate potency and selectivity at monoamine transporters is critical to identify and predict potential addictive drugs. This knowledge may allow prompt allocation of resources toward drugs that represent the greatest threats after drugs are identified by forensic laboratories.
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Affiliation(s)
- Vy T Nguyen
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Alan C Harris
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Jose M Eltit
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States.
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3
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Zhou J, Deng W, Chen C, Kang J, Yang X, Dou Z, Wu J, Li Q, Jiang M, Liang M, Han Y. Methcathinone Increases Visually-evoked Neuronal Activity and Enhances Sensory Processing Efficiency in Mice. Neurosci Bull 2023; 39:602-616. [PMID: 36449230 PMCID: PMC10073404 DOI: 10.1007/s12264-022-00965-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 07/18/2022] [Indexed: 12/02/2022] Open
Abstract
Methcathinone (MCAT) belongs to the designer drugs called synthetic cathinones, which are abused worldwide for recreational purposes. It has strong stimulant effects, including enhanced euphoria, sensation, alertness, and empathy. However, little is known about how MCAT modulates neuronal activity in vivo. Here, we evaluated the effect of MCAT on neuronal activity with a series of functional approaches. C-Fos immunostaining showed that MCAT increased the number of activated neurons by 6-fold, especially in sensory and motor cortices, striatum, and midbrain motor nuclei. In vivo single-unit recording and two-photon Ca2+ imaging revealed that a large proportion of neurons increased spiking activity upon MCAT administration. Notably, MCAT induced a strong de-correlation of population activity and increased trial-to-trial reliability, specifically during a natural movie stimulus. It improved the information-processing efficiency by enhancing the single-neuron coding capacity, suggesting a cortical network mechanism of the enhanced perception produced by psychoactive stimulants.
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Affiliation(s)
- Jun Zhou
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wen Deng
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Chen Chen
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Junya Kang
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xiaodan Yang
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Zhaojuan Dou
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jiancheng Wu
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Quancong Li
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Man Jiang
- Department of Physiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Man Liang
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Key Laboratory of Forensic Toxicology, Ministry of Public Security, Beijing, 100192, China.
| | - Yunyun Han
- Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Key Laboratory of Forensic Toxicology, Ministry of Public Security, Beijing, 100192, China.
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Impaired delay discounting and time sensitivity in methcathinone use disorder. Eur Arch Psychiatry Clin Neurosci 2022; 272:1595-1602. [PMID: 35091796 DOI: 10.1007/s00406-021-01372-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 12/10/2021] [Indexed: 11/03/2022]
Abstract
Substance use disorder (SUD) is characterized by continued drug use despite adverse consequences. Methcathinone is a new type of psychoactive substance that is associated with high excitement and impulsive behaviors. However, it is unclear if individuals with methcathinone use disorders (MCUD) are with impaired decision-making ability. We analyzed the task performance in 45 male MCUD subjects and 35 male matched healthy controls (HC) with intertemporal decision-making task. Constant sensitivity discounting model was used to estimate potential changes in both discounting rate and time sensitivity. The results showed that MCUD individuals exhibited a higher delay discounting rate (p = 0.003, Cohen's d = 0.683) and reduced sensitivity to time (p < 0.001, Cohen's d = 1.662). The delay discounting rate was correlated to the first age for drug use (r = - 0.41, p = 0.004), and the time sensitivity was negatively correlated with the duration of abstinence (r = - 0.31, p = 0.036). We conclude that MCUD individuals are with impaired decision-making ability and time perception disturbances.
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Huang H, Bai Y, Zhang Y, Huang J, Qin J, Li X. Occurrence and Transformation of Ephedrine/Pseudoephedrine and Methcathinone in Wastewater in China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10249-10257. [PMID: 35793412 DOI: 10.1021/acs.est.2c02639] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Previous wastewater-based epidemiology studies on methcathinone (MC), a controlled substance in many countries, attributed its occurrence in wastewater to its misuse. However, such attribution did not consider the possibility that MC may also come from the transformation of ephedrine (EPH) and pseudo-ephedrine (PEPH). In this work, EPH/PEPH and MC in wastewater of six major Chinese cities were systematically examined. EPH/PEPH concentrations in all the cities showed clear seasonal variations, with maximum and minimum concentrations observed in winter and summer, respectively. In contrast, MC concentrations were the lowest in winter, leading to minimum concentration ratios between MC and EPH/PEPH in winter. Lack of MC seizure in the cities suggests that MC abuse could not account for the ubiquitous detection of the substance in the wastewater of these cities. Batch experiments confirmed EPH/PEPH transformation into MC in wastewater. The significantly lower transformation rate at a lower temperature was consistent with low MC concentrations in winter. These results indicate that when monitoring MC through wastewater, EPH/PEPH concentrations must be determined simultaneously to avoid false identification of MC abuse. The observed ratios of MC to EPH/PEPH concentrations in this work may be used to determine MC abuse. Alternatively, other biomarkers (e.g., cathinone) may be considered to avoid interference from EPH/PEPH transformation.
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Affiliation(s)
- Hongmei Huang
- Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, P. R. China
| | - Ya Bai
- Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, P. R. China
| | - Yu Zhang
- Weiming Environmental Molecular Diagnostics Inc., Changshu 215500, Jiangsu Province, P.R. China
| | - Jianwen Huang
- Weiming Environmental Molecular Diagnostics Inc., Changshu 215500, Jiangsu Province, P.R. China
| | - Jun Qin
- Weiming Environmental Molecular Diagnostics Inc., Changshu 215500, Jiangsu Province, P.R. China
| | - Xiqing Li
- Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, P. R. China
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Magee CP, Le BD, Siripathane YH, Wilkins DG, Hanson GR, Fleckenstein AE. Methcathinone decreases dopamine transporter function: Role of protein kinase C. J Neurochem 2021; 159:116-127. [PMID: 34320222 DOI: 10.1111/jnc.15483] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 07/19/2021] [Accepted: 07/25/2021] [Indexed: 11/28/2022]
Abstract
Methcathinone (MCAT) is a psychostimulant of abuse that can cause both persistent striatal dopaminergic and serotonergic, as well as hippocampal serotonergic, deficits. Evidence suggests that the rapid effects of stimulants that are structurally and mechanistically similar to MCAT on monoamine transporter function may contribute to the abuse liability and/or persistent monoaminergic deficits caused by these agents. Thus, effects of MCAT on 1) striatal dopamine (DA) transporter (DAT); and 2) striatal and hippocampal serotonin transporter (SERT) function, as determined in tissues from adult male rats, were assessed. As reported previously, a single administration of MCAT rapidly (within 1 hr) decreases striatal [3 H]DA uptake. Similarly, incubation of rat synaptosomes with MCAT at 37℃ (but not 4˚C) decreased striatal [3 H]DA uptake. Incubation with MCAT likewise decreased [3 H]5HT but not vesicular [3 H]DA uptake. MCAT incubation in vitro was without effect on [3 H]DA uptake in striatal synaptosomes prepared from MCAT-treated rats. The decrease in [3 H]DA uptake caused by MCAT incubation: (a) reflected a decrease in Vmax , with minimal change in Km , and (b) was attenuated by co-incubation with the cell-permeable calcium chelator, N,N'-[1,2-ethanediylbis(oxy-2,1-phenylene)]bis[N-[2-[(acetyloxy)methoxy]-2-oxoethyl]-1,1'-bis[(acetyloxy)methyl] ester-glycine (BAPTA-AM), as well as the non-selective protein kinase-C (PKC) inhibitors bisindolylmaleimide-1 (BIM-1) and 2-[1-3(Aminopropyl)indol-3-yl]-3(1-methyl-1H-indol-3-yl)maleimide (or Bisindolylmaleimide VIII; Ro-31-7549). Taken together, these results suggest that in vitro MCAT incubation may model important aspects of MCAT administration in vivo, and that calcium and PKC contribute to the in vitro effects of MCAT on DAT.
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Affiliation(s)
- Charlotte P Magee
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA.,School of Dentistry, University of Utah, Salt Lake City, UT, USA
| | - BaoMinh D Le
- School of Dentistry, University of Utah, Salt Lake City, UT, USA
| | | | - Diana G Wilkins
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Glen R Hanson
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA.,School of Dentistry, University of Utah, Salt Lake City, UT, USA
| | - Annette E Fleckenstein
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA.,School of Dentistry, University of Utah, Salt Lake City, UT, USA
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Jîtcă G, Ősz BE, Tero-Vescan A, Vari CE. Psychoactive Drugs-From Chemical Structure to Oxidative Stress Related to Dopaminergic Neurotransmission. A Review. Antioxidants (Basel) 2021; 10:381. [PMID: 33806320 PMCID: PMC8000782 DOI: 10.3390/antiox10030381] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/24/2021] [Accepted: 03/01/2021] [Indexed: 12/26/2022] Open
Abstract
Nowadays, more and more young people want to experience illegal, psychoactive substances, without knowing the risks of exposure. Besides affecting social life, psychoactive substances also have an important effect on consumer health. We summarized and analyzed the published literature data with reference to the mechanism of free radical generation and the link between chemical structure and oxidative stress related to dopaminergic neurotransmission. This review presents data on the physicochemical properties, on the ability to cross the blood brain barrier, the chemical structure activity relationship (SAR), and possible mechanisms by which neuronal injuries occur due to oxidative stress as a result of drug abuse such as "bath salts", amphetamines, or cocaine. The mechanisms of action of ingested compounds or their metabolites involve intermediate steps in which free radicals are generated. The brain is strongly affected by the consumption of such substances, facilitating the induction of neurodegenerative diseases. It can be concluded that neurotoxicity is associated with drug abuse. Dependence and oxidative stress are linked to inhibition of neurogenesis and the onset of neuronal death. Understanding the pathological mechanisms following oxidative attack can be a starting point in the development of new therapeutic targets.
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Affiliation(s)
- George Jîtcă
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureș, 540142 Târgu Mureș, Romania; (G.J.); (C.E.V.)
| | - Bianca E. Ősz
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureș, 540142 Târgu Mureș, Romania; (G.J.); (C.E.V.)
| | - Amelia Tero-Vescan
- Department of Biochemistry, Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureș, 540142 Târgu Mureș, Romania;
| | - Camil E. Vari
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureș, 540142 Târgu Mureș, Romania; (G.J.); (C.E.V.)
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TANG W, CHANG J, WANG Y, WANG A, WANG R. [Research progress on chiral separation of amphetamines, ketamine, cathinones]. Se Pu 2021; 39:271-280. [PMID: 34227308 PMCID: PMC9403806 DOI: 10.3724/sp.j.1123.2020.05020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Indexed: 11/25/2022] Open
Abstract
Enantiomers are ubiquitous in nature, and they are especially important in the field of pharmaceutical chemistry. Although the enantiomers of chiral drugs have identical chemical structures, they differ notably in their pharmacological, toxicological, pharmacokinetic, metabolic, and other biological activities. The same is true for amphetamines, ketamine, and cathinones, as the chiral separation of these three drugs is representative of drugs. Gas chromatography (GC), high performance liquid chromatography (HPLC), and capillary electrophoresis (CE) are widely used for the chiral separation of these three kinds of drugs. There are some similarities among the three methods for the chiral separation of amphetamines, ketamine, and cathinones: n-trifluoroacetyl-L-prolinyl chloride and (+)R-α-methoxy-α-trifluoromethylphenylacetic acid are the two typical chiral derivatization reagents used in GC. In HPLC, three kinds of chiral stationary phases are used: proteins, polysaccharides, and macrocyclic antibiotics. Cyclodextrin and its derivatives are most commonly used in CE. However, these three methods have inherent shortcomings. In the case of GC, impurities produced during chiral derivatization may interfere with the analysis, and high reaction temperatures affect the efficiency of chiral separation. HPLC has limited application scope and is expensive. In CE, there has no established process to determine the appropriate chiral selector. In recent years, research into application of the chiral separation of the above-mentioned three kinds of drugs has its own characteristics in forensic toxicology. The chiral separation of amphetamine drugs is mostly used to infer the prototype and synthesis route of drugs on the market. The chiral separation of ketamine involves a variety of biological samples. For cathinones, chiral separation methods emphasize their wide applicability. In this review, 66 reports published in professional local and overseas magazines during the past decade are collated. The characteristics of the enantiomers of amphetamines, ketamine, and cathinones as well as the mechanism of chiral recognition are briefly introduced. The commonness of the research and the application of chiral separation in forensic toxicology are reviewed. This paper proposes that the chiral separation of drugs can be further investigated from the following three aspects: 1) the use of computer technology to establish a molecular model for exploring the mechanism of chiral recognition; 2) developing new technologies for chiral separation and carrying out commercial research on the supercritical fluid method; 3) applying chiral separation to judicial practice, pharmaceutical research and development, and other practical fields.
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Qin S, Zhang Y, He G, Xin G, Qiao J, Xu Z, Liu Y, Liu H, Wang Y, Lu J. Mass spectrometric characterization and identification of new methcathinone metabolites in human blood (plasma), urine and hair by liquid chromatography-high field quadrupole exactive orbitrap mass spectrometer. Microchem J 2020. [DOI: 10.1016/j.microc.2020.105423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Davies RA, Baird TR, Nguyen VT, Ruiz B, Sakloth F, Eltit JM, Negus SS, Glennon RA. Investigation of the Optical Isomers of Methcathinone, and Two Achiral Analogs, at Monoamine Transporters and in Intracranial Self-Stimulation Studies in Rats. ACS Chem Neurosci 2020; 11:1762-1769. [PMID: 32356961 PMCID: PMC10019599 DOI: 10.1021/acschemneuro.9b00617] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Methcathinone (MCAT; 1), the progenitor of numerous and widely abused "synthetic cathinone" central stimulants, exists as a pair of optical isomers. Although S(-)MCAT is several-fold more potent than R(+)MCAT in rodent locomotor stimulation and in stimulus generalization studies in rat drug discrimination assays, the individual optical isomers of MCAT have never been directly compared for their actions at monoamine transporters that seem to underlie their actions and have never been examined for their relative abuse potential. Here, we found that the isomers of MCAT are nearly equieffective at dopamine and norepinephrine transporters (DAT and NET, respectively) as transporter substrates (i.e., as releasing agents) and are ≥63-fold less potent at the serotonin transporter (SERT). In intracranial self-stimulation (ICSS) studies to evaluate abuse-related drug effects in rats, S(-)MCAT was approximately twice as potent as its R-enantiomer. Achiral analogs, α-methyl MCAT (3) and α-des-methyl MCAT (4), also were DAT/NET substrates and also produced abuse-related ICSS effects, indicating that they retain abuse potential and that they might be useful for the further study of the stereochemistry of synthetic cathinone analogs with chiral β- (or other) substituents.
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Asser A, Kõks S, Soomets U, Terasmaa A, Sauk M, Eltermaa M, Piip P, Ubhayasekera K, Bergquist J, Taba P. Acute effects of methcathinone and manganese in mice: A dose response study. Heliyon 2019; 5:e02475. [PMID: 31687570 PMCID: PMC6819833 DOI: 10.1016/j.heliyon.2019.e02475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 06/15/2019] [Accepted: 09/11/2019] [Indexed: 11/24/2022] Open
Abstract
An intravenously injectable illicit drug made by mixing pseudoephedrine, potassium permanganate, vinegar and water, yielding methcathinone (Mcat) and manganese (Mn), induces an extrapyramidal syndrome with parkinsonism, dystonia, gait and balance disorders similar to manganism. Although the cause of the syndrome is largely attributed to Mn, the interaction of the drug's individual components is not known and the role of Mcat is possibly underestimated. Aim of the present study was to analyze dose-dependent behavioral effects of the mixture and its two main active components Mcat and Mn in an acute setting and determine the lethal doses of each substance. Three groups of C57BL/6 mice were injected intraperitoneally with (1) the drug mixture containing 10, 25, 50, 100 or 150 mg of Mcat and respectively 1.6, 3.8, 6.9, 17.1 and 22.6 mg of Mn per kilogram of body weight; (2) 10, 25, 50, 100, 150, 200 or 300 mg of racemic Mcat/kg of body weight; (3) MnCl2 10, 25 or 50 mg/kg of body weight. Locomotor activity of the animals, various signs and time of death were recorded. Lower doses (10 and 25 mg/kg) of Mcat had a clear motor activity stimulating effect and this was clearly dose-dependent. High doses of Mcat produced epileptic seizures in 74% of the animals and became lethal with the highest doses. Similarly, the mixture had a clear dose-dependent stimulating effect and the higher doses became lethal. The LD50 of the pseudoephedrine mixture was 110.2 mg of Mcat/kg and for pure Mcat 201.7 mg/kg. Mn did not prove to be lethal in doses up to 50 mg/kg, but had a strong dose dependent inhibitory effect on the animals’ behavior. Our data reveal that both Mn and Mcat have a significant role in the toxicity of the mixture.
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Affiliation(s)
- Andres Asser
- Department of Neurology and Neurosurgery, University of Tartu, Puusepa 8, Tartu, 51014, Estonia
| | - Sulev Kõks
- Perron Institute for Neurological and Translational Science, University of Western Australia, Perth, WA, Australia
| | - Ursel Soomets
- Department of Biochemistry, University of Tartu, Ravila 19, Tartu, 50411, Estonia
| | - Anton Terasmaa
- Department of Physiology, University of Tartu, Ravila 19, Tartu, 50411, Estonia
| | - Martin Sauk
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, Tartu, 51010, Estonia
| | - Mall Eltermaa
- Institute of Biomedicine and Translational Medicine, University of Tartu, Ravila 19, Tartu, 50411, Estonia
| | - Piret Piip
- Department of Neurology and Neurosurgery, University of Tartu, Puusepa 8, Tartu, 51014, Estonia
| | - Kumari Ubhayasekera
- Department of Chemistry, Biomedical Center, Uppsala University, SE-751 24, Uppsala, Sweden
| | - Jonas Bergquist
- Department of Chemistry, Biomedical Center, Uppsala University, SE-751 24, Uppsala, Sweden
| | - Pille Taba
- Department of Neurology and Neurosurgery, University of Tartu, Puusepa 8, Tartu, 51014, Estonia
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The dopamine, serotonin and norepinephrine releasing activities of a series of methcathinone analogs in male rat brain synaptosomes. Psychopharmacology (Berl) 2019; 236:915-924. [PMID: 30341459 PMCID: PMC6475490 DOI: 10.1007/s00213-018-5063-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 10/02/2018] [Indexed: 12/12/2022]
Abstract
RATIONALE Novel synthetic "bath salt" cathinones continue to appear on the street as abused and addictive drugs. The range of subjective experiences produced by different cathinones suggests that some compounds have primarily dopaminergic activity (possible stimulants) while others have primarily serotonergic activity (possible empathogenics). An understanding of the structure activity relationships (SARs) of these compounds will help in assessing the likely behavioral effects of future novel structures, and to define potential therapeutic strategies to reverse any reinforcing effects. OBJECTIVES A series of methcathinone analogs was systematically studied for their activity at the dopamine and serotonin transporters. Compound structures varied at the aromatic group, either by substituent or by replacement of the phenyl ring with a naphthalene or indole ring. METHODS A novel, high-yielding synthesis of methcathinone hydrochlorides was developed which avoids isolation of the unstable free bases. Neurotransmitter transporter release activity was determined in rat brain synaptosomes as previously reported. Compounds were also screened for activity at the norepinephrine transporter. RESULTS Twenty-eight methcathinone analogs were analyzed and fully characterized in dopamine and serotonin transporter release assays. Compounds substituted at the 2-position (ortho) were primarily dopaminergic. Compounds substituted at the 3-position (meta) were found to be much less dopaminergic, with some substituents favoring serotonergic activity. Compounds substituted at the 4-position (para) were found to be far more serotonergic, as were disubstituted compounds and other large aromatic groups. One exception was the fluoro-substituted analogs which seem to favor the dopamine transporter. CONCLUSIONS The dopaminergic to serotonergic ratio can be manipulated by choice of substituent and location on the aromatic ring. It is therefore likely possible to tweak the subjective and reinforcing effects of these compounds by adjusting their structure. Certain substituents like a fluoro group tend to favor the dopamine transporter, while others like a trifluoromethyl group favor the serotonin transporter.
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Oliver CF, Palamar JJ, Salomone A, Simmons SJ, Philogene-Khalid HL, Stokes-McCloskey N, Rawls SM. Synthetic cathinone adulteration of illegal drugs. Psychopharmacology (Berl) 2019; 236:869-879. [PMID: 30338489 PMCID: PMC6472990 DOI: 10.1007/s00213-018-5066-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 10/03/2018] [Indexed: 01/28/2023]
Abstract
RATIONALE Current prevalence estimates of synthetic cathinone ("bath salt") use may be underestimates given that traditional metrics (e.g., surveys, urinalysis) often fail to capture the emergent issue of synthetic cathinone adulteration of more common illegal drugs, such as ecstasy (3,4-methylenedioxymethamphetamine). OBJECTIVES This review examines the evolution of synthetic cathinones and prevalence of use over the past decade in the United States. We also review methods of self-report and biological testing of these compounds as well as adverse outcomes associated with adulterated drug use. RESULTS Synthetic cathinone use emerged in the United States by 2009 with use associated with tens of thousands of poisonings. Reported poisonings and self-reported use have substantially decreased over the past five years. However, our review suggests that current estimates of use are underestimates due to underreporting stemming primarily from unknown or unintentional use of adulterated formulations of relatively popular illegal drugs, such as ecstasy. CONCLUSIONS While intentional synthetic cathinone use has decreased in recent years, evidence suggests that prevalence of use is underestimated. Testing of drugs and/or biological specimens can improve the accuracy of synthetic cathinone use estimates. Furthermore, we advocate that researchers and clinicians should become better aware that exposure to these potent compounds (e.g., as adulterants) often occurs unknowingly or unintentionally. To improve our understanding of synthetic cathinone adulteration, research utilizing a combinatorial approach (survey and biological testing) will help more accurately estimate the prevalence and impact of this public health issue.
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Affiliation(s)
- Chicora F Oliver
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, 3500 North Broad Street, 882A, Philadelphia, PA, 19140, USA.
| | - Joseph J Palamar
- Department of Population Health, 180 Madison Avenue Room 1752, New York, NY, 10016, USA
| | - Alberto Salomone
- Centro Regionale Antidoping "A. Bertinaria", Regione Gonzole 10/1, 10043, Orbassano, Torino, Italy
| | - Steven J Simmons
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, 3500 North Broad Street, 882A, Philadelphia, PA, 19140, USA
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, PA, 19104, USA
| | - Helene L Philogene-Khalid
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, 3500 North Broad Street, 882A, Philadelphia, PA, 19140, USA
- Department of Psychiatry, 100 E. Lehigh Ave, Philadelphia, PA, 19125, USA
| | - Nick Stokes-McCloskey
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, 3500 North Broad Street, 882A, Philadelphia, PA, 19140, USA
| | - Scott M Rawls
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, 3500 North Broad Street, 882A, Philadelphia, PA, 19140, USA
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Steele TWE, Eltit JM. Using Ca 2+-channel biosensors to profile amphetamines and cathinones at monoamine transporters: electro-engineering cells to detect potential new psychoactive substances. Psychopharmacology (Berl) 2019; 236:973-988. [PMID: 30448989 PMCID: PMC6525079 DOI: 10.1007/s00213-018-5103-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 11/02/2018] [Indexed: 01/20/2023]
Abstract
BACKGROUND The appearance of stimulant-class new psychoactive substances (NPS) is a frequent and significant problem in our society. Cathinone variants are often sold illegally as 3,4-methylenedioxy methamphetamine ("ecstasy") or disguised for legal sale using misleading names such as "bath salts" and carry the risk of promoting disruptive mental states, addiction, and fatal overdose. The principal targets of these recreational drugs are monoamine transporters expressed in catecholaminergic and serotonergic neurons. Some transporter ligands can be transported into cells, where they can promote a massive release of neurotransmitters through reverse transport, and others can block uptake. A ligand's dopamine vs. serotonin transporter selectivity, potency, and activity as a substrate or blocker can help elucidate the abuse liability and subjective effects of a drug. OBJECTIVES Here, we describe the discovery, development, and validation of an emerging methodology for compound activity assessment at monoamine transporters. KEY FINDINGS Substrates generate inward electrical currents through transporters and can depolarize the plasma membrane, whereas blockers work as a "cork in a bottle" and function as antagonists. Voltage-gated Ca2+ channels were co-expressed with monoamine transporters in cultured cells and used to measure fluctuations of the membrane electrical potential. In this system, substrates of monoamine transporters produce reliable dose-dependent Ca2+ signals, while blockers hinder them. DISCUSSION This system constitutes a novel use of voltage-gated Ca2+ channels as biosensors for the purpose of characterizing ligand activity at monoamine transporters using fluorimetry. This approach in combination with in vivo evaluations of drugs' abuse-related effects is a powerful strategy for anticipating potential stimulant-class NPS.
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Affiliation(s)
- Tyler W E Steele
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, 1101 E Marshall St. Rm# 3-038H, Richmond, VA, 23298, USA
| | - Jose M Eltit
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, 1101 E Marshall St. Rm# 3-038H, Richmond, VA, 23298, USA.
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Methcathinone and 3-Fluoromethcathinone Stimulate Spontaneous Horizontal Locomotor Activity in Mice and Elevate Extracellular Dopamine and Serotonin Levels in the Mouse Striatum. Neurotox Res 2018; 35:594-605. [PMID: 30377956 PMCID: PMC6420425 DOI: 10.1007/s12640-018-9973-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/07/2018] [Accepted: 10/19/2018] [Indexed: 12/23/2022]
Abstract
Methcathinone (MC) and 3-fluoromethcathinone (3-FMC) are well-known members of the synthetic cathinone derivatives, the second most abused group of novel psychoactive substances (NPS). They are considered as methamphetamine-like cathinones, as they elicit their psychostimulatory effects via inhibition of monoamine uptake and enhanced release. The present study examines the effects of MC and 3-FMC on the spontaneous locomotor activity of mice and extracellular levels of dopamine and serotonin in the mouse striatum. Both MC and 3-FMC produced a dose-dependent increase of horizontal locomotor activity, but no significant changes in rearing behavior were observed. The locomotor stimulation induced by MC and 3-FMC is mediated by activation of dopaminergic neurotransmission, as selective D1-dopamine receptor antagonist, SCH 23390, abolished the effects of both drugs. In line with pharmacological data obtained by previous in vitro studies, MC and 3-FMC produced potent increases of extracellular dopamine and serotonin levels in the mouse striatum. Taken together, results presented within this study confirm previous findings and expand our knowledge on the pharmacology of MC and 3-FMC along with their behavioral effects.
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Simmons SJ, Leyrer-Jackson JM, Oliver CF, Hicks C, Muschamp JW, Rawls SM, Olive MF. DARK Classics in Chemical Neuroscience: Cathinone-Derived Psychostimulants. ACS Chem Neurosci 2018; 9:2379-2394. [PMID: 29714473 DOI: 10.1021/acschemneuro.8b00147] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Cathinone is a plant alkaloid found in khat leaves of perennial shrubs grown in East Africa. Similar to cocaine, cathinone elicits psychostimulant effects which are in part attributed to its amphetamine-like structure. Around 2010, home laboratories began altering the parent structure of cathinone to synthesize derivatives with mechanisms of action, potencies, and pharmacokinetics permitting high abuse potential and toxicity. These "synthetic cathinones" include 4-methylmethcathinone (mephedrone), 3,4-methylenedioxypyrovalerone (MDPV), and the empathogenic agent 3,4-methylenedioxymethcathinone (methylone) which collectively gained international popularity following aggressive online marketing as well as availability in various retail outlets. Case reports made clear the health risks associated with these agents and, in 2012, the Drug Enforcement Agency of the United States placed a series of synthetic cathinones on Schedule I under emergency order. Mechanistically, cathinone and synthetic derivatives work by augmenting monoamine transmission through release facilitation and/or presynaptic transport inhibition. Animal studies confirm the rewarding and reinforcing properties of synthetic cathinones by utilizing self-administration, place conditioning, and intracranial self-stimulation assays and additionally show persistent neuropathological features which demonstrate a clear need to better understand this class of drugs. This Review will thus detail (i) historical context of cathinone use and the rise of "dark" synthetic derivatives, (ii) structural features and mechanisms of synthetic cathinones, (iii) behavioral effects observed clinically and in animals under controlled laboratory conditions, and (iv) neurotransmitters and circuits that may be targeted to manage synthetic cathinone abuse in humans.
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Affiliation(s)
- Steven J. Simmons
- Center for Substance Abuse Research (CSAR), Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | | | - Chicora F. Oliver
- Center for Substance Abuse Research (CSAR), Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Callum Hicks
- Center for Substance Abuse Research (CSAR), Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - John W. Muschamp
- Center for Substance Abuse Research (CSAR), Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - Scott M. Rawls
- Center for Substance Abuse Research (CSAR), Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania 19140, United States
| | - M. Foster Olive
- Department of Psychology, Arizona State University, Tempe, Arizona 85281, United States
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Simmons SJ, Kim E, Gentile TA, Murad A, Muschamp JW, Rawls SM. Behavioral Profiles and Underlying Transmitters/Circuits of Cathinone-Derived Psychostimulant Drugs of Abuse. CURRENT TOPICS IN NEUROTOXICITY 2018. [DOI: 10.1007/978-3-319-78707-7_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Abstract
Synthetic cathinones are derivatives of the naturally occurring compound cathinone, the main psychoactive ingredient in the khat plant Catha edulis. Cathinone is the β-keto analog of amphetamine, and all synthetic cathinones display a β-keto moiety in their structure. Several synthetic cathinones are widely prescribed medications (e.g., bupropion, Wellbutrin®), while others are problematic drugs of abuse (e.g., 4-methylmethcathinone, mephedrone). Similar to amphetamines, synthetic cathinones are psychomotor stimulants that exert their effects by impairing the normal function of plasma membrane transporters for dopamine (DAT), norepinephrine (NET), and 5-HT (SERT). Ring-substituted cathinones like mephedrone are transporter substrates that evoke neurotransmitter release by reversing the normal direction of transporter flux (i.e., releasers), whereas pyrrolidine-containing cathinones like 3,4-methylenedioxypyrovalerone (MDPV) are potent transporter inhibitors that block neurotransmitter uptake (i.e., blockers). Regardless of molecular mechanism, all synthetic cathinones increase extracellular monoamine concentrations in the brain, thereby enhancing cell-to-cell monoamine signaling. Here, we briefly review the mechanisms of action, structure-activity relationships, and in vivo pharmacology of synthetic cathinones. Overall, the findings show that certain synthetic cathinones are powerful drugs of abuse that could pose significant risk to users.
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Abstract
The present review briefly explores the neurotoxic properties of methcathinone, mephedrone, methylone, and methylenedioxypyrovalerone (MDPV), four synthetic cathinones most commonly found in "bath salts." Cathinones are β-keto analogs of the commonly abused amphetamines and display pharmacological effects resembling cocaine and amphetamines, but despite their commonalities in chemical structures, synthetic cathinones possess distinct neuropharmacological profiles and produce unique effects. Among the similarities of synthetic cathinones with their non-keto analogs are their targeting of monoamine systems, the release of neurotransmitters, and their stimulant properties. Most of the literature on synthetic cathinones has focused on describing their properties as psychostimulants, their behavioral effects on locomotion, memory, and potential for abuse, whereas descriptions of their neurotoxic properties are not abundant. The biochemical gauges of neurotoxicity induced by non-keto analogs are well studied in humans and experimental animals and include their ability to induce neuroinflammation, oxidative stress, excitotoxicity, temperature alterations as well as dysregulation of neurotransmitter systems and induce changes in monoamine transporters and receptors. These neurotoxicity gauges will serve as parameters to discuss the effects of the four previously mentioned synthetic cathinones alone or in combination with either another cathinone or with some of their non-keto analogs. Bath salts are not a defined combination of drugs and may consist of one synthetic cathinone compound or combinations of more cathinones. Furthermore, this review also presents some of the mechanisms that are thought to underlie this toxicity. A better understanding of the cellular and molecular mechanisms involved in the synthetic cathinones-induced neurotoxicity should contribute to generate modern therapeutic approaches to prevent or attenuate the adverse consequences of use of these drugs in humans.
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Affiliation(s)
- Mariana Angoa-Pérez
- Research & Development Service, John D. Dingell VA Medical Center, Detroit, MI, 48201, USA.
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
| | - John H Anneken
- Research & Development Service, John D. Dingell VA Medical Center, Detroit, MI, 48201, USA
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Donald M Kuhn
- Research & Development Service, John D. Dingell VA Medical Center, Detroit, MI, 48201, USA
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, 48201, USA
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Glennon RA. The 2014 Philip S. Portoghese Medicinal Chemistry Lectureship: The "Phenylalkylaminome" with a Focus on Selected Drugs of Abuse. J Med Chem 2017; 60:2605-2628. [PMID: 28244748 DOI: 10.1021/acs.jmedchem.7b00085] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The phenylalkylamine, particularly the phenylethylamine, moiety is a common structural feature found embedded in many clinically approved agents. Greater still is its occurrence in drugs of abuse. The simplest phenylethylamine, 2-phenylethylamine itself, is without significant central action when administered at moderate doses, but fairly simple structural modifications profoundly impact its pharmacology and result in large numbers of useful pharmacological tools, agents with therapeutic potential, and in drugs of abuse (e.g., hallucinogens, central stimulants, empathogens), the latter of which are the primary focus here. In vivo drug discrimination techniques and in vitro receptor/transporter methods have been applied to understand the actions of these phenylalkylamines and their mechanisms of action. Thus far, depending upon pendent substituents, certain receptors (e.g., serotonin receptors) and monoamine transporters (i.e., serotonin, dopamine, and norepinephrine transporters) have been implicated as playing major roles in the actions of these abused agents in a complex and, at times, interwoven manner.
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Affiliation(s)
- Richard A Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University , Richmond, Virginia 23298, United States
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21
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Shekar A, Aguilar JI, Galli G, Cozzi NV, Brandt SD, Ruoho AE, Baumann MH, Matthies HJG, Galli A. Atypical dopamine efflux caused by 3,4-methylenedioxypyrovalerone (MDPV) via the human dopamine transporter. J Chem Neuroanat 2017; 83-84:69-74. [PMID: 28163218 DOI: 10.1016/j.jchemneu.2017.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 01/20/2017] [Accepted: 01/24/2017] [Indexed: 10/20/2022]
Abstract
Synthetic cathinones are similar in chemical structure to amphetamines, and their behavioral effects are associated with enhanced dopaminergic signaling. The past ten years of research on the common constituent of bath salts, MDPV (the synthetic cathinone 3,4-methylenedioxypyrovalerone), has aided the understanding of how synthetic cathinones act at the dopamine (DA) transporter (DAT). Several groups have described the ability of MDPV to block the DAT with high-affinity. In this study, we demonstrate for the first time a new mode of action of MDPV, namely its ability to promote DAT-mediated DA efflux. Using single cell amperometric assays, we determined that low concentrations of MDPV (1nM) can cause reverse transport of DA via DAT. Notably, administration of MDPV leads to hyperlocomotion in Drosophila melanogaster. These data describe further how MDPV acts at the DAT, possibly paving the way for novel treatment strategies for individuals who abuse bath salts.
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Affiliation(s)
- Aparna Shekar
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-8548, United States; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232-8548, United States; Neuroscience Program in Substance Abuse (N-PISA), Vanderbilt University, Nashville, TN 37232-8548, United States
| | - Jenny I Aguilar
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232-8548, United States; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232-8548, United States; Neuroscience Program in Substance Abuse (N-PISA), Vanderbilt University, Nashville, TN 37232-8548, United States
| | - Greta Galli
- University School of Nashville, Nashville, TN 37212, United States
| | - Nicholas V Cozzi
- Neuropharmacology Laboratory, Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, United States
| | - Simon D Brandt
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool L3 3AF, UK
| | - Arnold E Ruoho
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, United States
| | - Michael H Baumann
- Designer Drug Research Unit (DDRU), Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, United States
| | - Heinrich J G Matthies
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232-8548, United States; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232-8548, United States
| | - Aurelio Galli
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232-8548, United States; Neuroscience Program in Substance Abuse (N-PISA), Vanderbilt University, Nashville, TN 37232-8548, United States; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232-8548, United States.
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Abstract
Until recently, there was rather little interest in the structure-activity relationships (SARs) of cathinone analogs because so few agents were available and because they represented a relatively minor drug abuse problem. Most of the early SAR was formulated on the basis of behavioral (e.g., locomotor and drug discrimination) studies using rodents. With the emergence on the clandestine market in the last few years of a large number of new cathinone analogs, termed "synthetic cathinones", and the realization that they likely act at dopamine, norepinephrine, and/or serotonin transporters as releasing agents (i.e., as substrates) or reuptake inhibitors (i.e., as transport blockers), it has now become possible to better examine their SAR and even their quantitative SAR (QSAR), in a more effective and systematic manner. An SAR picture is beginning to emerge, and key structural features, such as the nature of the terminal amine, the size of the α-substituent, stereochemistry, and the presence and position of aromatic substituents, are being found to impact action (i.e., as releasing agents or reuptake inhibitors) and transporter selectivity.
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Affiliation(s)
- Richard A Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA.
| | - Małgorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA
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Smith DA, Blough BE, Banks ML. Cocaine-like discriminative stimulus effects of amphetamine, cathinone, methamphetamine, and their 3,4-methylenedioxy analogs in male rhesus monkeys. Psychopharmacology (Berl) 2017; 234:117-127. [PMID: 27709249 PMCID: PMC5203958 DOI: 10.1007/s00213-016-4444-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 09/17/2016] [Indexed: 10/20/2022]
Abstract
RATIONALE Synthetic cathinones have emerged as the newest class of abused monoamine transporter substrates. Structurally, these compounds are all beta-ketone amphetamine (cathinone) analogs. Whether synthetic cathinone analogs produce differential behavioral effects from their amphetamine analog counterparts has not been systematically examined. Preclinical drug discrimination procedures have been useful for determining the structure activity relationships (SARs) of abused drugs; however, direct comparisons between amphetamine and cathinone analogs are lacking and, in particular, in non-human primate models. OBJECTIVES The study aim was to determine the potency and time course of (±)-amphetamine, (±)-cathinone, and (±)-methamphetamine and their 3,4-methylenedioxy analogs (±)-MDA, (±)-MDC, and (±)-MDMA, respectively, to produce cocaine-like discriminative stimulus effects. If cathinone analogs have similar behavioral pharmacological properties to their amphetamine counterparts, then we would predict similar potencies and efficacies to produce cocaine-like discriminative stimulus effects. METHODS Male rhesus monkeys (n = 4) were trained to discriminate intramuscular cocaine (0.32 mg/kg) from saline in a two-key food-reinforced discrimination procedure. RESULTS Racemic amphetamine, cathinone, and methamphetamine produced dose-dependent and full substitution, ≥90 % cocaine-appropriate responding, in all monkeys. Addition of 3,4-methylenedioxy moiety attenuated both the potency and efficacy of amphetamine (MDA), cathinone (MDC), and methamphetamine (MDMA) to produce full cocaine-like effects. Moreover, the cocaine-like effects of amphetamine and cathinone were attenuated to a greater extent than those of methamphetamine or previously published methcathinone (Smith et al. 2016). CONCLUSION The presence of an N-methyl group blunted both the potency and the efficacy shift of the 3,4-methylenedioxy addition for both amphetamine and cathinone analogs.
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Affiliation(s)
- Douglas A. Smith
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA USA 23298
| | - Bruce. E. Blough
- Center for Drug Discovery, Research Triangle Institute, Research Triangle Park, NC USA
| | - Matthew L. Banks
- Department of Pharmacology & Toxicology, Virginia Commonwealth University, Richmond, VA USA 23298,Corresponding Author: Matthew L. Banks, PharmD, PhD, Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 N. 12th St., PO Box 980613, Richmond, VA 23298, , Phone: 804-828-8466, Fax: 804-828-2117
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Baumann MH, Bukhari MO, Lehner KR, Anizan S, Rice KC, Concheiro M, Huestis MA. Neuropharmacology of 3,4-Methylenedioxypyrovalerone (MDPV), Its Metabolites, and Related Analogs. Curr Top Behav Neurosci 2017; 32:93-117. [PMID: 27830575 PMCID: PMC5392131 DOI: 10.1007/7854_2016_53] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
3,4-Methylenedioxypyrovalerone (MDPV) is a psychoactive component of so-called bath salts products that has caused serious medical consequences in humans. In this chapter, we review the neuropharmacology of MDPV and related analogs, and supplement the discussion with new results from our preclinical experiments. MDPV acts as a potent uptake inhibitor at plasma membrane transporters for dopamine (DAT) and norepinephrine (NET) in nervous tissue. The MDPV formulation in bath salts is a racemic mixture, and the S isomer is much more potent than the R isomer at blocking DAT and producing abuse-related effects. Elevations in brain extracellular dopamine produced by MDPV are likely to underlie its locomotor stimulant and addictive properties. MDPV displays rapid pharmacokinetics when injected into rats (0.5-2.0 mg/kg), with peak plasma concentrations achieved by 10-20 min and declining quickly thereafter. MDPV is metabolized to 3,4-dihydroxypyrovalerone (3,4-catechol-PV) and 4-hydroxy-3-methoxypyrovalerone (4-OH-3-MeO-PV) in vivo, but motor activation produced by the drug is positively correlated with plasma concentrations of parent drug and not its metabolites. 3,4-Catechol-PV is a potent uptake blocker at DAT in vitro but has little activity after administration in vivo. 4-OH-3-MeO-PV is the main MDPV metabolite but is weak at DAT and NET. MDPV analogs, such as α-pyrrolidinovalerophenone (α-PVP), display similar ability to inhibit DAT and increase extracellular dopamine concentrations. Taken together, these findings demonstrate that MDPV and its analogs represent a unique class of transporter inhibitors with a high propensity for abuse and addiction.
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Affiliation(s)
- Michael H Baumann
- Designer Drug Research Unit of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA.
| | - Mohammad O Bukhari
- Designer Drug Research Unit of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA
| | - Kurt R Lehner
- Designer Drug Research Unit of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA
| | - Sebastien Anizan
- Chemistry and Drug Metabolism Section of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA
| | - Kenner C Rice
- Drug Design and Synthesis Section of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA
| | - Marta Concheiro
- Chemistry and Drug Metabolism Section of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA
- Department of Sciences, John Jay College of Criminal Justice, City University of New York, New York, NY, USA
| | - Marilyn A Huestis
- Chemistry and Drug Metabolism Section of the Intramural Research Program, National Institute on Drug Abuse (NIDA), National Institutes of Health, Baltimore, MD, USA
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Juurmaa J, Menke RAL, Vila P, Müürsepp A, Tomberg T, Ilves P, Nigul M, Johansen-Berg H, Donaghy M, Stagg CJ, Stepens A, Taba P. Grey matter abnormalities in methcathinone abusers with a Parkinsonian syndrome. Brain Behav 2016; 6:e00539. [PMID: 27843694 PMCID: PMC5102639 DOI: 10.1002/brb3.539] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 06/29/2016] [Accepted: 07/02/2016] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND A permanent Parkinsonian syndrome occurs in intravenous abusers of the designer psychostimulant methcathinone (ephedrone). It is attributed to deposition of contaminant manganese, as reflected by characteristic globus pallidus hyperintensity on T1-weighted MRI. METHODS We have investigated brain structure and function in methcathinone abusers (n = 12) compared to matched control subjects (n = 12) using T1-weighted structural and resting-state functional MRI. RESULTS Segmentation analysis revealed significant (p < .05) subcortical grey matter atrophy in methcathinone abusers within putamen and thalamus bilaterally, and the left caudate nucleus. The volume of the caudate nuclei correlated inversely with duration of methcathinone abuse. Voxel-based morphometry showed patients to have significant grey matter loss (p < .05) bilaterally in the putamina and caudate nucleus. Surface-based analysis demonstrated nine clusters of cerebral cortical thinning in methcathinone abusers, with relative sparing of prefrontal, parieto-occipital, and temporal regions. Resting-state functional MRI analysis showed increased functional connectivity within the motor network of patients (p < .05), particularly within the right primary motor cortex. CONCLUSION Taken together, these results suggest that the manganese exposure associated with prolonged methcathinone abuse results in widespread structural and functional changes affecting both subcortical and cortical grey matter and their connections. Underlying the distinctive movement disorder caused by methcathinone abuse, there is a more widespread pattern of brain involvement than is evident from the hyperintensity restricted to the basal ganglia as shown by T1-weighted structural MRI.
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Affiliation(s)
- Julius Juurmaa
- Department of Neurology and Neurosurgery University of Tartu Tartu Estonia
| | - Ricarda A L Menke
- Nuffield Department of Clinical Neurosciences (NDCN) Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) University of Oxford Oxford UK; Department of Psychiatry University of Oxford Oxford UK
| | - Pierre Vila
- Nuffield Department of Clinical Neurosciences (NDCN) Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) University of Oxford Oxford UK
| | | | - Tiiu Tomberg
- Radiology Clinic Tartu University Hospital Tartu Estonia
| | - Pilvi Ilves
- Radiology Clinic Tartu University Hospital Tartu Estonia
| | - Mait Nigul
- Radiology Clinic Tartu University Hospital Tartu Estonia
| | - Heidi Johansen-Berg
- Nuffield Department of Clinical Neurosciences (NDCN) Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) University of Oxford Oxford UK
| | | | - Charlotte J Stagg
- Nuffield Department of Clinical Neurosciences (NDCN) Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) University of Oxford Oxford UK; Department of Psychiatry University of Oxford Oxford UK
| | - Ainārs Stepens
- Laboratory for Research in Rehabilitation Riga Stradins University Riga Latvia
| | - Pille Taba
- Department of Neurology and Neurosurgery University of Tartu Tartu Estonia
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Eshleman AJ, Wolfrum KM, Reed JF, Kim SO, Swanson T, Johnson RA, Janowsky A. Structure-Activity Relationships of Substituted Cathinones, with Transporter Binding, Uptake, and Release. J Pharmacol Exp Ther 2016; 360:33-47. [PMID: 27799294 DOI: 10.1124/jpet.116.236349] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 10/25/2016] [Indexed: 12/12/2022] Open
Abstract
Synthetic cathinones are components of "bath salts" and have physical and psychologic side effects, including hypertension, paranoia, and hallucinations. Here, we report interactions of 20 "bath salt" components with human dopamine, serotonin, and norepinephrine transporters [human dopamine transporter (hDAT), human serotonin transporter (hSERT), and human norepinephrine transporter (hNET), respectively] heterologously expressed in human embryonic kidney 293 cells. Transporter inhibitors had nanomolar to micromolar affinities (Ki values) at radioligand binding sites, with relative affinities of hDAT>hNET>hSERT for α-pyrrolidinopropiophenone (α-PPP), α-pyrrolidinobutiophenone, α-pyrrolidinohexiophenone, 1-phenyl-2-(1-pyrrolidinyl)-1-heptanone, 3,4-methylenedioxy-α-pyrrolidinopropiophenone, 3,4-methylenedioxy-α-pyrrolidinobutiophenone, 4-methyl-α-pyrrolidinopropiophenone, α-pyrrolidinovalerophenone, 4-methoxy-α-pyrrolidinovalerophenone, α-pyrrolidinopentiothiophenone (alpha-PVT), and α-methylaminovalerophenone, and hDAT>hSERT>hNET for methylenedioxypentedrone. Increasing the α-carbon chain length increased the affinity and potency of the α-pyrrolidinophenones. Uptake inhibitors had relative potencies of hDAT>hNET>hSERT except α-PPP and α-PVT, which had highest potencies at hNET. They did not induce [3H]neurotransmitter release. Substrates can enter presynaptic neurons via transporters, and the substrates methamphetamine and 3,4-methylenedioxymethylamphetamine are neurotoxic. We determined that 3-fluoro-, 4-bromo-, 4-chloro-methcathinone, and 4-fluoroamphetamine were substrates at all three transporters; 5,6-methylenedioxy-2-aminoindane (MDAI) and 4-methylethcathinone (4-MEC) were substrates primarily at hSERT and hNET; and 3,4-methylenedioxy-N-ethylcathinone (ethylone) and 5-methoxy-methylone were substrates only at hSERT and induced [3H]neurotransmitter release. Significant correlations between potencies for inhibition of uptake and for inducing release were observed for these and additional substrates. The excellent correlation of efficacy at stimulating release versus Ki/IC50 ratios suggested thresholds of binding/uptake ratios above which compounds were likely to be substrates. Based on their potencies at hDAT, most of these compounds have potential for abuse and addiction. 4-Bromomethcathinone, 4-MEC, 5-methoxy-methylone, ethylone, and MDAI, which have higher potencies at hSERT than hDAT, may have empathogen psychoactivity.
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Affiliation(s)
- Amy J Eshleman
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
| | - Katherine M Wolfrum
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
| | - John F Reed
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
| | - Sunyoung O Kim
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
| | - Tracy Swanson
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
| | - Robert A Johnson
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
| | - Aaron Janowsky
- Research Service, Portland VA Health Care System (A.J.E., K.M.W., J.F.R., S.O.K., T.S., R.A.J., A.J.), Departments of Psychiatry and Behavioral Neuroscience (A.J.E., A.J.), and Methamphetamine Abuse Research Center (T.S., A.J.), Oregon Health and Science University, Portland, Oregon
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Hutsell BA, Baumann MH, Partilla JS, Banks ML, Vekariya R, Glennon RA, Negus SS. Abuse-related neurochemical and behavioral effects of cathinone and 4-methylcathinone stereoisomers in rats. Eur Neuropsychopharmacol 2016; 26:288-297. [PMID: 26738428 PMCID: PMC5331761 DOI: 10.1016/j.euroneuro.2015.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 11/13/2015] [Accepted: 12/01/2015] [Indexed: 10/22/2022]
Abstract
Cathinone and many of its analogs produce behavioral effects by promoting transporter-mediated release of the monoamine neurotransmitters dopamine, norepinephrine and/or serotonin. Stereoselectivity is one determinant of neurochemical and behavioral effects of cathinone analogs. This study compared effectiveness of the S(-) and R(+) enantiomers of cathinone and 4-methylcathinone to produce in vitro monoamine release and in vivo abuse-related behavioral effects in rats. For neurochemical studies, drug effects were evaluated on monoamine release through dopamine, norepinephrine, and serotonin transporters (DAT, NET and SERT, respectively) in rat brain synaptosomes. For behavioral studies, drug effects were evaluated on responding for electrical brain stimulation in an intracranial self-stimulation (ICSS) procedure. The cathinone enantiomers differed in potency [S(-)>R(+)], but both enantiomers were >50-fold selective at promoting monoamine release through DAT vs. SERT, and both enantiomers produced ICSS facilitation. The 4-methylcathinone enantiomers also differed in potency [S(-)>R(+)]; however, in neurochemical studies, the decrease in potency from S(-) to R(+)4-methylcathinone was less for DAT than for SERT, and as a result, DAT vs. SERT selectivity was greater for R(+) than for S(-)4-methylcathinone (4.1- vs. 1.2-fold). Moreover, in behavioral studies, S(-)4-methylcathinone produced only ICSS depression, whereas R(+)4-methylcathinone produced ICSS facilitation. This study provides further evidence for stereoselectivity in neurochemical and behavioral actions of cathinone analogs. More importantly, stereoselective 4-methylcathinone effects on ICSS illustrate the potential for diametrically opposite effects of enantiomers in a preclinical behavioral assay of abuse potential.
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Affiliation(s)
- Blake A Hutsell
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 N. 12th St., PO Box 980613, Richmond, VA 23298, USA
| | - Michael H Baumann
- Designer Drug Research Unit, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - John S Partilla
- Designer Drug Research Unit, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Matthew L Banks
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 N. 12th St., PO Box 980613, Richmond, VA 23298, USA; Institute for Drug and Alcohol Studies, Virginia Commonwealth University, USA
| | - Rakesh Vekariya
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, USA
| | - Richard A Glennon
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, USA
| | - S Stevens Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 N. 12th St., PO Box 980613, Richmond, VA 23298, USA; Institute for Drug and Alcohol Studies, Virginia Commonwealth University, USA.
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Suyama JA, Sakloth F, Kolanos R, Glennon RA, Lazenka MF, Negus SS, Banks ML. Abuse-Related Neurochemical Effects of Para-Substituted Methcathinone Analogs in Rats: Microdialysis Studies of Nucleus Accumbens Dopamine and Serotonin. J Pharmacol Exp Ther 2015; 356:182-90. [PMID: 26645638 DOI: 10.1124/jpet.115.229559] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 10/14/2015] [Indexed: 11/22/2022] Open
Abstract
Methcathinone (MCAT) is a monoamine releaser and parent compound to a new class of designer drugs that includes the synthetic cathinones mephedrone and flephedrone. Using MCAT and a series of para-substituted (or 4-substituted) MCAT analogs, it has been previously shown that expression of abuse-related behavioral effects in rats correlates both with the volume of the para substituent and in vitro neurochemical selectivity to promote monoamine release via the dopamine (DA) versus serotonin (5-HT) transporters in rat brain synaptosomes. The present study used in vivo microdialysis to determine the relationship between these previous measures and the in vivo neurochemical selectivity of these compounds to alter nucleus accumbens (NAc) DA and 5-HT levels. Male Sprague-Dawley rats were implanted with bilateral guide cannulae targeting the NAc. MCAT and five para-substituted analogs (4-F, 4-Cl, 4-Br, 4-CH3, and 4-OCH3) produced dose- and time-dependent increases in NAc DA and/or 5-HT levels. Selectivity was determined as the dose required to increase peak 5-HT levels by 250% divided by the dose required to increase peak DA levels by 250%. This measure of in vivo neurochemical selectivity varied across compounds and correlated with 1) in vivo expression of abuse-related behavioral effects (r = 0.89, P = 0.02); 2) in vitro selectivity to promote monoamine release via DA and 5-HT transporters (r = 0.95, P < 0.01); and 3) molecular volume of the para substituent (r = -0.85, P = 0.03). These results support a relationship between these molecular, neurochemical, and behavioral measures and support a role for molecular structure as a determinant of abuse-related neurochemical and behavioral effects of MCAT analogs.
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Affiliation(s)
- Julie A Suyama
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
| | - Farhana Sakloth
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
| | - Renata Kolanos
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
| | - Richard A Glennon
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
| | - Matthew F Lazenka
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
| | - S Stevens Negus
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
| | - Matthew L Banks
- Department of Pharmacology and Toxicology (J.A.S., M.F.L., S.S.N., M.L.B.), Department of Medicinal Chemistry (F.S., R.K., R.A.G.), and Institute on Drug and Alcohol Studies (R.A.G., S.S.N., M.L.B.), Virginia Commonwealth University, Richmond, Virginia
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Sakloth F, Kolanos R, Mosier PD, Bonano JS, Banks ML, Partilla JS, Baumann MH, Negus SS, Glennon RA. Steric parameters, molecular modeling and hydropathic interaction analysis of the pharmacology of para-substituted methcathinone analogues. Br J Pharmacol 2015; 172:2210-8. [PMID: 25522019 PMCID: PMC4403088 DOI: 10.1111/bph.13043] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/24/2014] [Accepted: 11/30/2014] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND AND PURPOSE There is growing concern over the abuse of certain psychostimulant methcathinone (MCAT) analogues. This study extends an initial quantitative structure-activity relationship (QSAR) investigation that demonstrated important steric considerations of seven 4- (or para-)substituted analogues of MCAT. Specifically, the steric character (Taft's steric ES ) of the 4-position substituent affected in vitro potency to induce monoamine release via dopamine and 5-HT transporters (DAT and SERT) and in vivo modulation of intracranial self-stimulation (ICSS). Here, we have assessed the effects of other steric properties of the 4-position substituents. EXPERIMENTAL APPROACH Definitive steric parameters that more explicitly focus on the volume, width and length of the MCAT 4-position substituents were assessed. In addition, homology models of human DAT and human SERT based upon the crystallized Drosophila DAT were constructed and docking studies were performed, followed by hydropathic interaction (HINT) analysis of the docking results. KEY RESULTS The potency of seven MCAT analogues at DAT was negatively correlated with the volume and maximal width of their 4-position substituents, whereas potency at SERT increased as substituent volume and length increased. SERT/DAT selectivity, as well as abuse-related drug effects in the ICSS procedure, also correlated with the same parameters. Docking solutions offered a means of visualizing these findings. CONCLUSIONS AND IMPLICATIONS These results suggest that steric aspects of the 4-position substituents of MCAT analogues are key determinants of their action and selectivity, and that the hydrophobic nature of these substituents is involved in their potency at SERT.
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Affiliation(s)
- F Sakloth
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth UniversityRichmond, VA, USA
| | - R Kolanos
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth UniversityRichmond, VA, USA
| | - P D Mosier
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth UniversityRichmond, VA, USA
| | - J S Bonano
- Department of Pharmacology and Toxicology, Virginia Commonwealth UniversityRichmond, VA, USA
| | - M L Banks
- Department of Pharmacology and Toxicology, Virginia Commonwealth UniversityRichmond, VA, USA
| | - J S Partilla
- Designer Drug Research Unit, Intramural Research Program, National Institute on Drug Abuse, National Institutes of HealthBaltimore, MD, USA
| | - M H Baumann
- Designer Drug Research Unit, Intramural Research Program, National Institute on Drug Abuse, National Institutes of HealthBaltimore, MD, USA
| | - S S Negus
- Department of Pharmacology and Toxicology, Virginia Commonwealth UniversityRichmond, VA, USA
| | - R A Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth UniversityRichmond, VA, USA
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Bonano JS, Banks ML, Kolanos R, Sakloth F, Barnier ML, Glennon RA, Cozzi NV, Partilla JS, Baumann MH, Negus SS. Quantitative structure-activity relationship analysis of the pharmacology of para-substituted methcathinone analogues. Br J Pharmacol 2015; 172:2433-44. [PMID: 25438806 DOI: 10.1111/bph.13030] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/20/2014] [Accepted: 11/27/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Methcathinone (MCAT) is a potent monoamine releaser and parent compound to emerging drugs of abuse including mephedrone (4-CH3 MCAT), the para-methyl analogue of MCAT. This study examined quantitative structure-activity relationships (QSAR) for MCAT and six para-substituted MCAT analogues on (a) in vitro potency to promote monoamine release via dopamine and serotonin transporters (DAT and SERT, respectively), and (b) in vivo modulation of intracranial self-stimulation (ICSS), a behavioural procedure used to evaluate abuse potential. Neurochemical and behavioural effects were correlated with steric (Es ), electronic (σp ) and lipophilic (πp ) parameters of the para substituents. EXPERIMENTAL APPROACH For neurochemical studies, drug effects on monoamine release through DAT and SERT were evaluated in rat brain synaptosomes. For behavioural studies, drug effects were tested in male Sprague-Dawley rats implanted with electrodes targeting the medial forebrain bundle and trained to lever-press for electrical brain stimulation. KEY RESULTS MCAT and all six para-substituted analogues increased monoamine release via DAT and SERT and dose- and time-dependently modulated ICSS. In vitro selectivity for DAT versus SERT correlated with in vivo efficacy to produce abuse-related ICSS facilitation. In addition, the Es values of the para substituents correlated with both selectivity for DAT versus SERT and magnitude of ICSS facilitation. CONCLUSIONS AND IMPLICATIONS Selectivity for DAT versus SERT in vitro is a key determinant of abuse-related ICSS facilitation by these MCAT analogues, and steric aspects of the para substituent of the MCAT scaffold (indicated by Es ) are key determinants of this selectivity.
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Affiliation(s)
- J S Bonano
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
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Hohmann N, Mikus G, Czock D. Effects and risks associated with novel psychoactive substances: mislabeling and sale as bath salts, spice, and research chemicals. DEUTSCHES ARZTEBLATT INTERNATIONAL 2015; 111:139-47. [PMID: 24661585 DOI: 10.3238/arztebl.2014.0139] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 01/07/2014] [Accepted: 01/07/2014] [Indexed: 11/27/2022]
Abstract
BACKGROUND The number of newly reported psychoactive substances in Europe is now higher than ever. In order to evade legal restrictions, old and novel psychoactive substances from medical research and their derivatives are commonly mislabeled as "not for human consumption" and offered for sale on the Internet and elsewhere. Such substances are widely taken by young people as "club drugs." Their consumption must be considered in the differential diagnosis of psychiatric, neurological, cardiovascular, or metabolic disturbances of unclear origin in a young patient. METHOD Selective review of pertinent literature retrieved by a PubMed search, including publications by government-sponsored organizations. RESULTS From 2010 to 2012, 163 substances were reported to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), mostly either synthetic cannabinoids (39.3%) or synthetic cathinones (16.6%). Synthetic cannabinoids alter mood and perception; intoxications cause agitation, tachy cardia, and arterial hypertension. Synthetic cathinones are hallucinogenic stimulants with predominantly cardiovascular and psychiatric side effects. Severe intoxications cause serotonin syndrome and potentially fatal rhabdomyolysis. Substances in either of these classes often escape detection in screening tests. CONCLUSION Young persons who present with agitation and cardiovascular and/or psychiatric manifestations of unclear origin and whose drug screening tests are negative may be suffering from an intoxication with a novel psychoactive substance. Physicians should know the classes of such substances and their effects. Targeted toxicological analysis can be carried out in a toxicology laboratory or a facility for forensic medicine.
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Affiliation(s)
- Nicolas Hohmann
- Department of Clinical Pharmacology and Pharmacoepidemiology, Heidelberg University Hospital
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Gatch MB, Rutledge MA, Forster MJ. Discriminative and locomotor effects of five synthetic cathinones in rats and mice. Psychopharmacology (Berl) 2015; 232:1197-205. [PMID: 25281225 PMCID: PMC4361374 DOI: 10.1007/s00213-014-3755-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/20/2014] [Indexed: 11/25/2022]
Abstract
RATIONALE Synthetic cathinones continue to be sold as "legal" alternatives to methamphetamine or cocaine. As these marginally legal compounds become controlled, suppliers move to other, unregulated compounds. OBJECTIVES The purpose of these experiments was to determine whether several temporarily controlled cathinone compounds, which are currently abused on the street, stimulate motor activity and have discriminative stimulus effects similar to cocaine and/or methamphetamine. METHODS Methcathinone, pentedrone, pentylone, 3-fluoromethcathinone (3-FMC), and 4-methylethcathinone (4-MEC) were tested for locomotor stimulant effects in mice and subsequently for substitution in rats trained to discriminate cocaine (10 mg/kg, i.p.) or methamphetamine (1 mg/kg, i.p.) from saline. RESULTS Methcathinone, pentedrone, and pentylone produced locomotor stimulant effects which lasted up to 6 h. In addition, pentylone produced convulsions and lethality at 100 mg/kg. 4-MEC produced locomotor stimulant effects which lasted up to 2 h. Methcathinone, pentedrone, pentylone, 3-FMC, and 4-MEC each produced discriminative stimulus effects similar to those of cocaine and methamphetamine. CONCLUSIONS All of the tested compounds produce discriminative stimulus effects similar to either those of cocaine, methamphetamine, or both, which suggests that these compounds are likely to have similar abuse liability to cocaine and/or methamphetamine. Pentylone may be more dangerous on the street, as it produced adverse effects at doses that produced maximal stimulant-like effects.
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Affiliation(s)
- Michael B Gatch
- Pharmacology & Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107-2699, USA,
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Zhou MJ, Bouazzaoui S, Jones LE, Goodrich P, Bell SEJ, Sheldrake GN, Horton PN, Coles SJ, Fletcher NC. Isolation and structural determination of non-racemic tertiary cathinone derivatives. Org Biomol Chem 2015; 13:9629-36. [DOI: 10.1039/c5ob01306b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper the dynamic resolution of racemic tertiary cathinones is demonstrated through co-crystallization with enantiopure aromatic tartaric acids.
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Affiliation(s)
- M.-J. Zhou
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - S. Bouazzaoui
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - L. E. Jones
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - P. Goodrich
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - S. E. J. Bell
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - G. N. Sheldrake
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
| | - P. N. Horton
- University of Southampton
- Chemistry Department
- EPSRC National Crystallography Service
- Southampton
- UK
| | - S. J. Coles
- University of Southampton
- Chemistry Department
- EPSRC National Crystallography Service
- Southampton
- UK
| | - N. C. Fletcher
- School of Chemistry and Chemical Engineering
- Queen's University Belfast
- Belfast
- UK
- Department of Chemistry
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Kaizaki A, Tanaka S, Numazawa S. New recreational drug 1-phenyl-2-(1-pyrrolidinyl)-1-pentanone (alpha-PVP) activates central nervous system via dopaminergic neuron. J Toxicol Sci 2014; 39:1-6. [PMID: 24418703 DOI: 10.2131/jts.39.1] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
1-phenyl-2-(1-pyrrolidinyl)-1-pentanone (α-PVP) is a new designer drug of the cathinone type. People who have taken drugs containing α-PVP or other synthetic cathinone reportedly lose consciousness, develop difficulty breathing, and at worst case, die. However, the mechanism underlying α-PVP-induced neurotoxicity is unknown. The objective of the present study was to investigate the effect of α-PVP on the central nervous system (CNS) and compare its neurotoxicity with that of methamphetamine (METH) in mice. Balb/c male mice (8 weeks old) were orally administered α-PVP (25 mg/kg) or METH (5 mg/kg). α-PVP induced a significant increase in locomotor activity, which occurred earlier than locomotor activity induced by METH. This increase was inhibited by the D1 receptor antagonist SCH23990 (50 µg/kg, i.p.) and the D2 receptor antagonist sulpiride (50 mg/kg, i.m.). The extracellular concentration of dopamine (DA) in the striatum, determined by in vivo microdialysis increased immediately after α-PVP administration. These results suggest that α-PVP stimulates DA release, causing an increase in locomotor activity, and that this stimulatory effect of α-PVP on CNS is mediated, at least in part, by the D1 and D2 receptors.
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Affiliation(s)
- Asuka Kaizaki
- Division of Toxicology, Department of Pharmacology, Toxicology and Therapeutics, Showa University School of Pharmacy
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35
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Blough BE, Landavazo A, Partilla JS, Baumann MH, Decker AM, Page KM, Rothman RB. Hybrid dopamine uptake blocker-serotonin releaser ligands: a new twist on transporter-focused therapeutics. ACS Med Chem Lett 2014; 5:623-7. [PMID: 24944732 DOI: 10.1021/ml500113s] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 04/15/2014] [Indexed: 11/29/2022] Open
Abstract
As part of our program to study neurotransmitter releasers, we report herein a class of hybrid dopamine reuptake inhibitors that display serotonin releasing activity. Hybrid compounds are interesting since they increase the design potential of transporter related compounds and hence represent a novel and unexplored strategy for therapeutic drug discovery. A series of N-alkylpropiophenones was synthesized and assessed for uptake inhibition and release activity using rat brain synaptosomes. Substitution on the aromatic ring yielded compounds that maintained hybrid activity, with the two disubstituted analogues (PAL-787 and PAL-820) having the most potent hybrid activity.
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Affiliation(s)
- Bruce E. Blough
- Center for Drug
Discovery, Discovery-Science-Technology, RTI International, 3040
Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
| | - Antonio Landavazo
- Center for Drug
Discovery, Discovery-Science-Technology, RTI International, 3040
Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
| | - John S. Partilla
- Medicinal Chemistry Section, Intramural
Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Michael H. Baumann
- Medicinal Chemistry Section, Intramural
Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Ann M. Decker
- Center for Drug
Discovery, Discovery-Science-Technology, RTI International, 3040
Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
| | - Kevin M. Page
- Center for Drug
Discovery, Discovery-Science-Technology, RTI International, 3040
Cornwallis Road, Research Triangle Park, North Carolina 27709, United States
| | - Richard B. Rothman
- Medicinal Chemistry Section, Intramural
Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, United States
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Paillet-Loilier M, Cesbron A, Le Boisselier R, Bourgine J, Debruyne D. Emerging drugs of abuse: current perspectives on substituted cathinones. Subst Abuse Rehabil 2014; 5:37-52. [PMID: 24966713 PMCID: PMC4043811 DOI: 10.2147/sar.s37257] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Substituted cathinones are synthetic analogs of cathinone that can be considered as derivatives of phenethylamines with a beta-keto group on the side chain. They appeared in the recreational drug market in the mid-2000s and now represent a large class of new popular drugs of abuse. Initially considered as legal highs, their legal status is variable by country and is rapidly changing, with government institutions encouraging their control. Some cathinones (such as diethylpropion or pyrovalerone) have been used in a medical setting and bupropion is actually indicated for smoking cessation. Substituted cathinones are widely available from internet websites, retail shops, and street dealers. They can be sold under chemical, evocative or generic names, making their identification difficult. Fortunately, analytical methods have been developed in recent years to solve this problem. Available as powders, substituted cathinones are self-administered by snorting, oral injestion, or intravenous injection. They act as central nervous system stimulants by causing the release of catecholamines (dopamine, noradrenaline, and serotonin) and blocking their reuptake in the central and peripheral nervous system. They may also decrease dopamine and serotonin transporter function as nonselective substrates or potent blockers and may inhibit monoamine oxidase effects. Nevertheless, considerable differences have been found in the potencies of the different substituted cathinones in vitro. Desired effects reported by users include increased energy, empathy, and improved libido. Cardiovascular (tachycardia, hypertension) and psychiatric/neurological signs/symptoms (agitation, seizures, paranoia, and hallucinations) are the most common adverse effects reported. Severe toxicity signs compatible with excessive serotonin activity, such as hyperthermia, metabolic acidosis, and prolonged rhabdomyolysis, have also been observed. Reinforcing potential observed in animals predicts a high potential for addiction and abuse in users. In case of overdose, no specific antidote exists and no curative treatment has been approved by health authorities. Therefore, management of acute toxic effects is mainly extrapolated from experience with cocaine/amphetamines.
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Affiliation(s)
| | - Alexandre Cesbron
- Toxicology and Pharmacology Laboratory, University Hospital Centre, Caen, France
| | - Reynald Le Boisselier
- Centre d'Evaluation et d'Information sur la Pharmacodépendance - Addictovigilance (CEIP-A), Department of Pharmacology, University Hospital Centre, Caen, France
| | - Joanna Bourgine
- Toxicology and Pharmacology Laboratory, University Hospital Centre, Caen, France
| | - Danièle Debruyne
- Toxicology and Pharmacology Laboratory, University Hospital Centre, Caen, France ; Centre d'Evaluation et d'Information sur la Pharmacodépendance - Addictovigilance (CEIP-A), Department of Pharmacology, University Hospital Centre, Caen, France
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Li L, Lurie IS. Screening of seized emerging drugs by ultra-high performance liquid chromatography with photodiode array ultraviolet and mass spectrometric detection. Forensic Sci Int 2014; 237:100-11. [DOI: 10.1016/j.forsciint.2014.01.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 01/20/2014] [Accepted: 01/26/2014] [Indexed: 11/24/2022]
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Banks ML, Worst TJ, Rusyniak DE, Sprague JE. Synthetic cathinones ("bath salts"). J Emerg Med 2014; 46:632-42. [PMID: 24565885 DOI: 10.1016/j.jemermed.2013.11.104] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 10/11/2013] [Accepted: 11/17/2013] [Indexed: 11/18/2022]
Abstract
BACKGROUND Synthetic cathinones are popularly referred to in the media as "bath salts." Through the direct and indirect activation of the sympathetic nervous system, smoking, snorting, or injecting synthetic cathinones can result in tachycardia, hypertension, hyperthermia, myocardial infarction, and death. OBJECTIVE The chemical structures and names of bath salts identified by the Ohio Attorney General's Bureau of Criminal Investigation are presented. Based on their common pharmacophores, we review the history, pharmacology, toxicology, detection methods, and clinical implications of synthetic cathinones. Through the integration of this information, the pharmacological basis for the management of patients using synthetic cathinones is presented. DISCUSSION Synthetic cathinones activate central serotonergic and dopaminergic systems contributing to acute psychosis and the peripheral activation of the sympathetic nervous system. The overstimulation of the sympathetic nervous system contributes to the many toxicities reported with bath salt use. The pharmacological basis for managing these patients is targeted at attenuating the activation of these systems. CONCLUSIONS Treatment of patients presenting after using bath salts should be focused on reducing agitation and psychosis and supporting renal perfusion. The majority of successfully treated synthetic cathinones cases have used benzodiazepines and antipsychotics along with general supportive care.
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Affiliation(s)
- Matthew L Banks
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia
| | - Travis J Worst
- Ohio Attorney General's Bureau of Criminal Investigation, London, Ohio
| | - Daniel E Rusyniak
- Departments of Emergency Medicine and Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jon E Sprague
- Department of Pharmaceutical Sciences, College of Pharmacy, Ferris State University, Big Rapids, Michigan
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Hudson AL, Lalies MD, Baker GB, Wells K, Aitchison KJ. Ecstasy, legal highs and designer drug use: A Canadian perspective. ACTA ACUST UNITED AC 2014. [DOI: 10.1177/2050324513509190] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recreational drug use in Canada is not uncommon, but as with most societies, illegal drug use carries harsh penalties resulting in a criminal record when an individual is successfully prosecuted. Popular drugs of use in Canada include ecstasy, cannabis (including some synthetic cannabinoids sold as ‘Spice’ and ‘Incense’) and several emerging psychoactive ‘legal highs’. Surprisingly, Canada is a major manufacturer and exporter of the popular club drug ecstasy, with criminal gangs organising the synthesis and distribution of this club drug worldwide. Over the last 18 months, there has been much interest in and use of alternatives to ecstasy due to contamination of ecstasy during synthesis. One particular contaminant, paramethoxymethamphetamine (PMMA), has resulted in several deaths. Other alternatives include piperazines and mephedrone analogues. With regard to cannabis, some is home grown within people’s properties, but there is also large-scale cultivation in British Columbia where the climate is more temperate. With the introduction of corporate drug screening, there is increasing use of synthetic cannabinoids to avoid detection of marijuana use. This article discusses the problems and trends of synthetic drug use in Canada and reflects on the limited education available to youth in this regard.
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Iversen L, White M, Treble R. Designer psychostimulants: pharmacology and differences. Neuropharmacology 2014; 87:59-65. [PMID: 24456744 DOI: 10.1016/j.neuropharm.2014.01.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 12/19/2013] [Accepted: 01/09/2014] [Indexed: 11/29/2022]
Abstract
More than 200 novel psychoactive drugs have been reported in Europe, with 73 added in 2012 and additional compounds encountered every week in 2013. Many of these are "designer psychostimulants" which aim to mimic the subjective effects of amphetamines, cocaine or 3,4-methylenedioxymethylamphetamine (MDMA; "Ecstasy"). Several drugs are based on the beta-ketoamphetamine cathinone chemical structure, others include aminoindanes, aminotetralins, piperazines, amphetamine analogues and pipradrol derivatives. Although a detailed analysis of the pharmacology of these novel drugs is largely lacking, a number of scientific studies have been reported in 2011-2013 and these are reviewed. All of the novel psychostimulants activate monoamine systems in the brain - with differing dopamine (DA) v serotonin (5-HT) preferences. Those activating principally DA systems are amphetamine-like stimulants, such as naphyrone, desoxypipradrol, 3,4-methylenedioxypyrovalerone (MDPV), and benzylpiperazine while those preferentially activating 5-HT mechanisms are MDMA-like or cocaine-like stimulants, such as mephedrone, methylone and other substituted cathinones, aminoindanes, aminotetralins and piperazines. The ability of mephedrone and other novel psychostimulants to substitute for methylamphetamine or cocaine in drug discrimination tests in rats, and the ability of mephedrone to induce conditioned place preference and to sustain self-administration behaviour suggests that this and other cocaine/methylamphetamine-like drugs have dependence liability. This article is part of the Special Issue entitled 'CNS Stimulants'.
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Affiliation(s)
- Leslie Iversen
- Department of Pharmacology, University of Oxford, Mansfield Road, OX1 3QT, UK.
| | - Michael White
- Forensic Adviser, Advisory Council on the Misuse of Drugs (ACMD) Secretariat, 2 Marsham Street, London SW1P 4DP, UK
| | - Ric Treble
- LGC Forensics, Queens Road, Teddington, London TW11 0LY, UK
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Abuse-related and abuse-limiting effects of methcathinone and the synthetic "bath salts" cathinone analogs methylenedioxypyrovalerone (MDPV), methylone and mephedrone on intracranial self-stimulation in rats. Psychopharmacology (Berl) 2014; 231:199-207. [PMID: 23949206 PMCID: PMC3877726 DOI: 10.1007/s00213-013-3223-5] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 07/20/2013] [Indexed: 10/26/2022]
Abstract
RATIONALE Abuse of synthetic cathinones, popularized as "bath salts," has increased dramatically in the USA since their debut in 2010. Preclinical behavioral studies may clarify determinants of the abuse-related effects produced by these compounds. OBJECTIVES This study examined behavioral effects of (±)-methcathinone, (±)-3,4-methylenedioxypyrovalerone (MDPV), (±)-3,4-methylenedioxymethcathinone (methylone), and (±)-4-methylmethcathinone (mephedrone) in rats using intracranial self-stimulation (ICSS). METHODS Male Sprague-Dawley rats (n = 18) with electrodes targeting the medial forebrain bundle responded for multiple frequencies of brain stimulation and were tested in two phases. First, dose-effect curves for methcathinone (0.1-1.0 mg/kg), MDPV (0.32-3.2 mg/kg), methylone (1.0-10 mg/kg), and mephedrone (1.0-10 mg/kg) were determined. Second, time courses were determined for effects produced by the highest dose of each compound. RESULTS Methcathinone produced dose- and time-dependent facilitation of ICSS. MDPV, methylone, and mephedrone produced dose- and time-dependent increases in low rates of ICSS maintained by low brain stimulation frequencies, but also produced abuse-limiting depression of high ICSS rates maintained by high brain stimulation frequencies. Efficacies to facilitate ICSS were methcathinone ≥ MDPV ≥ methylone > mephedrone. Methcathinone was the most potent compound, and MDPV was the longest acting compound. CONCLUSIONS All compounds facilitated ICSS at some doses and pretreatment times, which is consistent with abuse liability for each of these compounds. However, efficacies of compounds to facilitate ICSS varied, with methcathinone displaying the highest efficacy and mephedrone displaying the lowest efficacy to facilitate ICSS.
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Glennon RA. Bath salts, mephedrone, and methylenedioxypyrovalerone as emerging illicit drugs that will need targeted therapeutic intervention. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 69:581-620. [PMID: 24484988 PMCID: PMC4471862 DOI: 10.1016/b978-0-12-420118-7.00015-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The term "synthetic cathinones" is fairly new, but, although the abuse of synthetic cathinones is a recent problem, research on cathinone analogs dates back >100 years. One structural element cathinone analogs have in common is an α-aminophenone moiety. Introduction of amine and/or aryl substituents affords a large number of agents. Today, >40 synthetic cathinones have been identified on the clandestine market and many have multiple "street names." Many cathinone analogs, although not referred to as such until the late 1970s, were initially prepared as intermediates in the synthesis of ephedrine analogs. The cathinones do not represent a pharmacologically or mechanistically homogeneous class of agents. Currently abused synthetic cathinones are derived from earlier agents and seem to produce their actions primarily via the dopamine, norepinephrine, and/or serotonin transporter; that is, they either release and/or inhibit the reuptake of one or more of these neurotransmitters. The actions of these agents can resemble those of central stimulants such as methamphetamine, cocaine, and/or empathogens such as 1-(3,4-methylenedioxyphenyl)-2-aminopropane (Ecstasy) and/or produce other effects. Side effects are primarily of a neurological and/or cardiovascular nature. The use of the "and/or" term is emphasized because synthetic cathinones represent a broad class of agents that produce a variety of actions; the agents cannot be viewed as being pharmacologically equivalent. Until valid structure-activity relationships are formulated for each behavioral/mechanistic action, individual synthetic cathinones remain to be evaluated on a case-by-case basis. Treatment of synthetic cathinone intoxication requires more "basic science" research. At this time, treatment is mostly palliative.
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Affiliation(s)
- Richard A. Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298-0540 USA
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43
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Kolanos R, Solis E, Sakloth F, De Felice LJ, Glennon RA. "Deconstruction" of the abused synthetic cathinone methylenedioxypyrovalerone (MDPV) and an examination of effects at the human dopamine transporter. ACS Chem Neurosci 2013; 4:1524-9. [PMID: 24116392 PMCID: PMC3867964 DOI: 10.1021/cn4001236] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 10/09/2013] [Indexed: 11/30/2022] Open
Abstract
Synthetic cathinones, β-keto analogues of amphetamine (or, more correctly, of phenylalkylamines), represent a new and growing class of abused substances. Several such analogues have been demonstrated to act as dopamine (DA) releasing agents. Methylenedioxypyrovalerone (MDPV) was the first synthetic cathinone shown to act as a cocaine-like DA reuptake inhibitor. MDPV and seven deconstructed analogues were examined to determine which of MDPV's structural features account(s) for uptake inhibition. In voltage-clamped (-60 mV) Xenopus oocytes transfected with the human DA transporter (hDAT), all analogues elicited inhibitor-like behavior shown as hDAT-mediated outward currents. Using hDAT-expressing mammalian cells we determined the affinities of MDPV and its analogues to inhibit uptake of [3H]DA by hDAT that varied over a broad range (IC50 values ca. 135 to >25,000 nM). The methylenedioxy group of MDPV made a minimal contribution to affinity, the carbonyl group and a tertiary amine are more important, and the extended α-alkyl group seems most important. Either a tertiary amine, or the extended α-alkyl group (but not both), are required for the potent nature of MDPV as an hDAT inhibitor.
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Affiliation(s)
- Renata Kolanos
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Ernesto Solis
- Department
of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Farhana Sakloth
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Louis J. De Felice
- Department
of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Richard A. Glennon
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
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Cameron KN, Kolanos R, Solis E, Glennon RA, De Felice LJ. Bath salts components mephedrone and methylenedioxypyrovalerone (MDPV) act synergistically at the human dopamine transporter. Br J Pharmacol 2013; 168:1750-7. [PMID: 23170765 DOI: 10.1111/bph.12061] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 10/20/2012] [Accepted: 11/09/2012] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Bath salts is the street name for drug combinations that contain synthetic cathinone analogues, among them possibly mephedrone (MEPH) and certainly methylenedioxypyrovalerone (MDPV). In animal studies, cathinone and certain cathinone analogues release dopamine (DA), similar to the action of amphetamine (AMPH) and methamphetamine (METH). AMPH and METH act on the human DA transporter (hDAT); thus, we investigated MEPH and MDPV acting at hDAT. EXPERIMENTAL APPROACH We recorded electrical currents mediated by hDAT expressed in Xenopus laevis oocytes and exposed to: DA, METH, a known hDAT stimulant and DA releaser, MEPH, MDPV, MEPH + MDPV, or cocaine, a known hDAT inhibitor. KEY RESULTS DA, METH and MEPH induce an inward current (depolarizing) when the oocyte is held near the resting potential (-60 mV), therefore acting as excitatory hDAT substrates. Structurally analogous MDPV induces an outward (hyperpolarizing) current similar to cocaine, therefore acting as an inhibitory non-substrate blocker. CONCLUSIONS AND IMPLICATIONS Two components of bath salts, MEPH and MDPV, produce opposite effects at hDAT that are comparable with METH and cocaine, respectively. In our assay, MEPH is nearly as potent as METH; however, MDPV is much more potent than cocaine and its effect is longer lasting. When applied in combination, MEPH exhibits faster kinetics than MDPV, viz., the MEPH depolarizing current occurs seconds before the slower MDPV hyperpolarizing current. Bath salts containing MEPH (or a similar drug) and MDPV might then be expected initially to release DA and subsequently prevent its reuptake via hDAT. Such combined action possibly underlies some of the reported effects of bath salts abuse.
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Affiliation(s)
- Krasnodara N Cameron
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA 23298, USA
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Synthetic cathinones: chemical phylogeny, physiology, and neuropharmacology. Life Sci 2013; 97:20-6. [PMID: 24231923 DOI: 10.1016/j.lfs.2013.10.029] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 10/22/2013] [Accepted: 10/25/2013] [Indexed: 11/21/2022]
Abstract
This mini-review summarizes the history of cathinone and its synthesized derivatives from early records to the present day, including the appearance of synthetic cathinones in the drug combination known as bath salts. Bath salts may consist of one compound (MDPV) or combinations of MDPV and one or more other synthetic cathinones, which may also appear alone without MDPV. We briefly review recent in vitro studies of bath salts components alone or in combination, focusing on pharmacological and biophysical studies. Finally we summarize new data from in vivo procedures that characterize the abuse-related neurochemical and behavioral effects of synthetic cathinones in rats.
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Emergence and properties of spice and bath salts: a medicinal chemistry perspective. Life Sci 2013; 97:9-19. [PMID: 24113072 DOI: 10.1016/j.lfs.2013.09.026] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 09/17/2013] [Accepted: 09/25/2013] [Indexed: 11/21/2022]
Abstract
Over the past five years the number of internet sites advertising "legal highs" has literally exploded, as have user reports of experiences (both pleasurable and frightening) with these substances and the number of emergency room visits by users. Although the majority of these "legal highs" have been described as bath salts and herbal extracts, most contain neither plant derived compounds nor components of personal hygiene products. So-called "bath salts" largely contain synthetic analogs of the natural compound Khat; spice-related materials, claimed to be "legal marijuana," are mostly synthetic analogs of cannabinoid receptor ligands that were developed as research tools. This review describes the emergence and properties of these two groups of "legal highs" from a medicinal chemist's perspective.
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Effects of methcathinone and 3-Cl-methcathinone (PAL-434) in cocaine discrimination or self-administration in rhesus monkeys. Int J Neuropsychopharmacol 2013; 16:1985-98. [PMID: 23768644 DOI: 10.1017/s146114571300059x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Monoamine releasers with varying selectivity for dopamine (DA)/norepinephrine and serotonin (5-HT) release are potential treatment medications for cocaine abuse. Although DA-selective monoamine releasers effectively reduce cocaine abuse, their clinical usefulness is limited by abuse liability. It is hypothesized that increasing 5-HT neurotransmission may reduce the abuse-related effects of DA releasers, but the optimal DA:5-HT release ratio remains to be determined. This study in rhesus monkeys compared the effects of two compounds with differing potency for 5-HT release. Methcathinone and 3-Cl-methcathinone (PAL-434) have equal potency for DA release, but PAL-434 has 10-fold higher potency for 5-HT release. In drug discrimination studies, monkeys were trained to discriminate cocaine (0.4 mg/kg i.m.) from saline in a two-key, food-reinforced procedure. In drug self-administration studies, a separate group of monkeys was trained to respond for cocaine [0.01 mg/kg/injection (inj)] and food (1 g pellets) under a second order schedule of reinforcement [FR2(VR16:S)]. When responding was stable, methcathinone (0.1–0.56 mg/kg.h i.v.) or PAL-434 (0.32–1.8 mg/kg.h i.v.) was administered chronically (one injection every 20 min for 23 h/d) for 7–10 d. In discrimination studies, both compounds dose-dependently increased cocaine-like responding but with different potencies (cocaine=methcathinone >PAL-434). Chronic treatment with methcathinone or PAL-434 dose-dependently and selectively reduced cocaine self-administration. PAL-434 was about 4-fold and methcathinone about 1.6-fold more potent at decreasing cocaine- over food-maintained responding. These data suggest that compounds with moderate selectivity for DA vs. 5-HT release (8–15-fold) may be effective for the treatment of cocaine dependence.
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Increases in use of novel synthetic stimulant are not directly linked to decreased use of 3,4-methylenedioxy-N-methylamphetamine (MDMA). Forensic Sci Int 2013; 231:278-83. [DOI: 10.1016/j.forsciint.2013.06.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/24/2013] [Accepted: 06/09/2013] [Indexed: 11/17/2022]
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Mephedrone and methylenedioxypyrovalerone (MDPV), major constituents of "bath salts," produce opposite effects at the human dopamine transporter. Psychopharmacology (Berl) 2013; 227:493-9. [PMID: 23371489 PMCID: PMC3881434 DOI: 10.1007/s00213-013-2967-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 01/04/2013] [Indexed: 10/27/2022]
Abstract
RATIONALE Psychoactive "bath salts" represent a relatively new drug of abuse combination that was placed in Schedule I in October 2011. Two common ingredients of bath salts include the cathinone analogs: mephedrone and methylenedioxypyrovalerone (MDPV). The mechanism of action of these synthetic cathinone analogs has not been well investigated. MATERIALS AND METHODS Because cathinone and methcathinone are known to act as releasing agents at the human dopamine transporter (hDAT), mephedrone and MDPV were investigated at hDAT expressed in Xenopus oocytes. RESULTS Whereas mephedrone was found to have the signature of a dopamine-releasing agent similar to methamphetamine or methcathinone, MDPV behaved as a cocaine-like reuptake inhibitor of dopamine. CONCLUSIONS Mephedrone and MDPV produce opposite electrophysiological signatures through hDAT expressed in oocytes. Implications are that the combination (as found in bath salts) might produce effects similar to a combination of methamphetamine and cocaine.
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Eshleman AJ, Wolfrum KM, Hatfield MG, Johnson RA, Murphy KV, Janowsky A. Substituted methcathinones differ in transporter and receptor interactions. Biochem Pharmacol 2013; 85:1803-15. [PMID: 23583454 DOI: 10.1016/j.bcp.2013.04.004] [Citation(s) in RCA: 184] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/03/2013] [Accepted: 04/03/2013] [Indexed: 12/31/2022]
Abstract
The use of synthetic methcathinones, components of "bath salts," is a world-wide health concern. These compounds, structurally similar to methamphetamine (METH) and 3,4-methylendioxymethamphetamine (MDMA), cause tachycardia, hallucinations and psychosis. We hypothesized that these potentially neurotoxic and abused compounds display differences in their transporter and receptor interactions as compared to amphetamine counterparts. 3,4-Methylenedioxypyrovalerone and naphyrone had high affinity for radioligand binding sites on recombinant human dopamine (hDAT), serotonin (hSERT) and norepinephrine (hNET) transporters, potently inhibited [³H]neurotransmitter uptake, and, like cocaine, did not induce transporter-mediated release. Butylone was a lower affinity uptake inhibitor. In contrast, 4-fluoromethcathinone, mephedrone and methylone had higher inhibitory potency at uptake compared to binding and generally induced release of preloaded [³H]neurotransmitter from hDAT, hSERT and hNET (highest potency at hNET), and thus are transporter substrates, similar to METH and MDMA. At hNET, 4-fluoromethcathinone was a more efficacious releaser than METH. These substituted methcathinones had low uptake inhibitory potency and low efficacy at inducing release via human vesicular monoamine transporters (hVMAT2). These compounds were low potency (1) h5-HT(1A) receptor partial agonists, (2) h5-HT(2A) receptor antagonists, (3) weak h5-HT(2C) receptor antagonists. This is the first report on aspects of substituted methcathinone efficacies at serotonin (5-HT) receptors and in superfusion release assays. Additionally, the drugs had no affinity for dopamine receptors, and high-nanomolar to mid-micromolar affinity for hSigma1 receptors. Thus, direct interactions with hVMAT2 and serotonin, dopamine, and hSigma1 receptors may not explain psychoactive effects. The primary mechanisms of action may be as inhibitors or substrates of DAT, SERT and NET.
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Affiliation(s)
- Amy J Eshleman
- Research Service, Veterans Affairs Medical Center, Portland, OR, USA.
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