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Vaughan RA, Henry LK, Foster JD, Brown CR. Post-translational mechanisms in psychostimulant-induced neurotransmitter efflux. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2024; 99:1-33. [PMID: 38467478 DOI: 10.1016/bs.apha.2023.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
The availability of monoamine neurotransmitters in the brain is under the control of dopamine, norepinephrine, and serotonin transporters expressed on the plasma membrane of monoaminergic neurons. By regulating transmitter levels these proteins mediate crucial functions including cognition, attention, and reward, and dysregulation of their activity is linked to mood and psychiatric disorders of these systems. Amphetamine-based transporter substrates stimulate non-exocytotic transmitter efflux that induces psychomotor stimulation, addiction, altered mood, hallucinations, and psychosis, thus constituting a major component of drug neurochemical and behavioral outcomes. Efflux is under the control of transporter post-translational modifications that synergize with other regulatory events, and this review will summarize our knowledge of these processes and their role in drug mechanisms.
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Affiliation(s)
- Roxanne A Vaughan
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States.
| | - L Keith Henry
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
| | - James D Foster
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
| | - Christopher R Brown
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
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2
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Shetty M, Bolland DE, Morrell J, Grove BD, Foster JD, Vaughan RA. Dopamine transporter membrane mobility is bidirectionally regulated by phosphorylation and palmitoylation. Curr Res Physiol 2023; 6:100106. [PMID: 38107792 PMCID: PMC10724222 DOI: 10.1016/j.crphys.2023.100106] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 09/20/2023] [Indexed: 12/19/2023] Open
Abstract
The primary regulator of dopamine availability in the brain is the dopamine transporter (DAT), a plasma membrane protein that drives reuptake of released dopamine from the extracellular space into the presynaptic neuron. DAT activity is regulated by post-translational modifications that establish clearance capacity through impacts on transport kinetics, and dysregulation of these events may underlie dopaminergic imbalances in mood and psychiatric disorders. Here, using fluorescence recovery after photobleaching, we show that phosphorylation and palmitoylation induce opposing effects on DAT lateral membrane mobility, which may influence functional outcomes by regulating subcellular localization and binding partner interactions. Membrane mobility was also impacted by amphetamine and in polymorphic variant A559V in directions consistent with enhanced phosphorylation. These findings grow the list of DAT properties controlled by these post-translational modifications and highlight their role in establishment of dopaminergic tone in physiological and pathophysiological states.
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Affiliation(s)
- Madhur Shetty
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND, 58202, USA
| | | | - Joshua Morrell
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND, 58202, USA
| | - Bryon D. Grove
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND, 58202, USA
| | - James D. Foster
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND, 58202, USA
| | - Roxanne A. Vaughan
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND, 58202, USA
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3
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Shekar A, Mabry SJ, Cheng MH, Aguilar JI, Patel S, Zanella D, Saleeby DP, Zhu Y, Romanazzi T, Ulery-Reynolds P, Bahar I, Carter AM, Matthies HJG, Galli A. Syntaxin 1 Ser 14 phosphorylation is required for nonvesicular dopamine release. SCIENCE ADVANCES 2023; 9:eadd8417. [PMID: 36630507 PMCID: PMC9833662 DOI: 10.1126/sciadv.add8417] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 12/14/2022] [Indexed: 05/30/2023]
Abstract
Amphetamine (AMPH) is a psychostimulant that is commonly abused. The stimulant properties of AMPH are associated with its ability to increase dopamine (DA) neurotransmission. This increase is promoted by nonvesicular DA release mediated by reversal of DA transporter (DAT) function. Syntaxin 1 (Stx1) is a SNARE protein that is phosphorylated at Ser14 by casein kinase II. We show that Stx1 phosphorylation is critical for AMPH-induced nonvesicular DA release and, in Drosophila melanogaster, regulates the expression of AMPH-induced preference and sexual motivation. Our molecular dynamics simulations of the DAT/Stx1 complex demonstrate that phosphorylation of these proteins is pivotal for DAT to dwell in a DA releasing state. This state is characterized by the breakdown of two key salt bridges within the DAT intracellular gate, causing the opening and hydration of the DAT intracellular vestibule, allowing DA to bind from the cytosol, a mechanism that we hypothesize underlies nonvesicular DA release.
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Affiliation(s)
- Aparna Shekar
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Samuel J. Mabry
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mary H. Cheng
- Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jenny I. Aguilar
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Shalin Patel
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Daniele Zanella
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - David P. Saleeby
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yanqi Zhu
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Tiziana Romanazzi
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | | | - Ivet Bahar
- Department of Computational and Systems Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Angela M. Carter
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Aurelio Galli
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
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4
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Nepal B, Das S, Reith ME, Kortagere S. Overview of the structure and function of the dopamine transporter and its protein interactions. Front Physiol 2023; 14:1150355. [PMID: 36935752 PMCID: PMC10020207 DOI: 10.3389/fphys.2023.1150355] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 02/21/2023] [Indexed: 03/06/2023] Open
Abstract
The dopamine transporter (DAT) plays an integral role in dopamine neurotransmission through the clearance of dopamine from the extracellular space. Dysregulation of DAT is central to the pathophysiology of numerous neuropsychiatric disorders and as such is an attractive therapeutic target. DAT belongs to the solute carrier family 6 (SLC6) class of Na+/Cl- dependent transporters that move various cargo into neurons against their concentration gradient. This review focuses on DAT (SCL6A3 protein) while extending the narrative to the closely related transporters for serotonin and norepinephrine where needed for comparison or functional relevance. Cloning and site-directed mutagenesis experiments provided early structural knowledge of DAT but our contemporary understanding was achieved through a combination of crystallization of the related bacterial transporter LeuT, homology modeling, and subsequently the crystallization of drosophila DAT. These seminal findings enabled a better understanding of the conformational states involved in the transport of substrate, subsequently aiding state-specific drug design. Post-translational modifications to DAT such as phosphorylation, palmitoylation, ubiquitination also influence the plasma membrane localization and kinetics. Substrates and drugs can interact with multiple sites within DAT including the primary S1 and S2 sites involved in dopamine binding and novel allosteric sites. Major research has centered around the question what determines the substrate and inhibitor selectivity of DAT in comparison to serotonin and norepinephrine transporters. DAT has been implicated in many neurological disorders and may play a role in the pathology of HIV and Parkinson's disease via direct physical interaction with HIV-1 Tat and α-synuclein proteins respectively.
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Affiliation(s)
- Binod Nepal
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Sanjay Das
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Maarten E. Reith
- Department of Psychiatry, New York University School of Medicine, New York City, NY, United States
| | - Sandhya Kortagere
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States
- *Correspondence: Sandhya Kortagere,
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5
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Zegers-Delgado J, Blanlot C, Calderon F, Yarur HE, Novoa J, Vega-Quiroga I, Bastias CP, Gysling K. Reactive oxygen species modulate locomotor activity and dopamine extracellular levels induced by amphetamine in rats. Behav Brain Res 2022; 427:113857. [PMID: 35331742 DOI: 10.1016/j.bbr.2022.113857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 03/07/2022] [Accepted: 03/18/2022] [Indexed: 11/25/2022]
Abstract
The increase of dopamine (DA) in the reward system is related to the reinforcing effects of drugs of abuse and hyper locomotion induced by psychostimulants. The increase of DA induced by drugs of abuse ge nerates high amounts of ROS by monoamines metabolization. It has been showed that ROS could modulate psychomotor response and reinforcing effects induced by drugs of abuse as cocaine and methamphetamine (METH). The aim of this study is to evaluate the relation of ROS and amphetamine (AMPH). Here, we show that pretreatment of the ROS scavenger 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) attenuates the induction of locomotion and oxidative stress generated in nucleus accumbens (Nac) by acute AMPH administration. Interestingly, TEMPOL also attenuates the increase of DA induced by AMPH in Nac. Finally, TEMPOL reduces DAT phosphorylation when AMPH is co-infused in Nac synaptosomes. Taking together, our results suggest that ROS modulate AMPH effects in rats.
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Affiliation(s)
- Juan Zegers-Delgado
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile.
| | - Camila Blanlot
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile
| | - Florencia Calderon
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile
| | - Hector E Yarur
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile
| | - Javier Novoa
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile
| | - Ignacio Vega-Quiroga
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile
| | - Cristian P Bastias
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile
| | - Katia Gysling
- Department of Cellular and Molecular Biology, Millenium Science Nucleus in Stress and Addiction, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, 8331150, Chile.
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6
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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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7
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Shin EJ, Jeong JH, Nguyen BT, Sharma N, Nah SY, Chung YH, Lee Y, Byun JK, Nabeshima T, Ko SK, Kim HC. Ginsenoside Re Protects against Serotonergic Behaviors Evoked by 2,5-Dimethoxy-4-iodo-amphetamine in Mice via Inhibition of PKCδ-Mediated Mitochondrial Dysfunction. Int J Mol Sci 2021; 22:ijms22137219. [PMID: 34281274 PMCID: PMC8268959 DOI: 10.3390/ijms22137219] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/26/2021] [Accepted: 06/29/2021] [Indexed: 02/07/2023] Open
Abstract
It has been recognized that serotonin 2A receptor (5-HT2A) agonist 2,5-dimethoxy-4-iodo-amphetamine (DOI) impairs serotonergic homeostasis. However, the mechanism of DOI-induced serotonergic behaviors remains to be explored. Moreover, little is known about therapeutic interventions against serotonin syndrome, although evidence suggests that ginseng might possess modulating effects on the serotonin system. As ginsenoside Re (GRe) is well-known as a novel antioxidant in the nervous system, we investigated whether GRe modulates 5-HT2A receptor agonist DOI-induced serotonin impairments. We proposed that protein kinase Cδ (PKCδ) mediates serotonergic impairments. Treatment with GRe or 5-HT2A receptor antagonist MDL11939 significantly attenuated DOI-induced serotonergic behaviors (i.e., overall serotonergic syndrome behaviors, head twitch response, hyperthermia) by inhibiting mitochondrial translocation of PKCδ, reducing mitochondrial glutathione peroxidase activity, mitochondrial dysfunction, and mitochondrial oxidative stress in wild-type mice. These attenuations were in line with those observed upon PKCδ inhibition (i.e., pharmacologic inhibitor rottlerin or PKCδ knockout mice). Furthermore, GRe was not further implicated in attenuation mediated by PKCδ knockout in mice. Our results suggest that PKCδ is a therapeutic target for GRe against serotonergic behaviors induced by DOI.
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Affiliation(s)
- Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Korea; (E.-J.S.); (B.-T.N.); (N.S.)
| | - Ji Hoon Jeong
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, College of Medicine, Chung-Ang University, Seoul 06974, Korea;
| | - Bao-Trong Nguyen
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Korea; (E.-J.S.); (B.-T.N.); (N.S.)
| | - Naveen Sharma
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Korea; (E.-J.S.); (B.-T.N.); (N.S.)
- Department of Global Innovative Drugs, Graduate School of Chung-Ang University, College of Medicine, Chung-Ang University, Seoul 06974, Korea;
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory, Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 05029, Korea;
| | - Yoon Hee Chung
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul 06974, Korea;
| | - Yi Lee
- Department of Industrial Plant Science & Technology, Chungbuk National University, Chungju 28644, Korea;
| | - Jae Kyung Byun
- Korea Society of Forest Environmental Research, Namyanju 12106, Korea;
| | - Toshitaka Nabeshima
- Advanced Diagnostic System Research Laboratory, Fujita Health University Graduate School of Health Science, Toyoake 470-1192, Japan;
| | - Sung Kwon Ko
- Department of Oriental Medical Food and Nutrition, Semyung University, Jecheon 27136, Korea
- Correspondence: (S.K.K.); (H.-C.K.); Tel.: +82-33-250-6917 (H.-C.K.); Fax: +82-33-259-5631 (H.-C.K.)
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Korea; (E.-J.S.); (B.-T.N.); (N.S.)
- Correspondence: (S.K.K.); (H.-C.K.); Tel.: +82-33-250-6917 (H.-C.K.); Fax: +82-33-259-5631 (H.-C.K.)
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8
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Meinke C, Quinlan MA, Paffenroth KC, Harrison FE, Fenollar-Ferrer C, Katamish RM, Stillman I, Ramamoorthy S, Blakely RD. Serotonin Transporter Ala276 Mouse: Novel Model to Assess the Neurochemical and Behavioral Impact of Thr276 Phosphorylation In Vivo. Neurochem Res 2021; 47:37-60. [PMID: 33830406 DOI: 10.1007/s11064-021-03299-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 02/21/2021] [Accepted: 03/17/2021] [Indexed: 11/30/2022]
Abstract
The serotonin (5-HT) transporter (SERT) is a key regulator of 5-HT signaling and is a major target for antidepressants and psychostimulants. Human SERT coding variants have been identified in subjects with obsessive-compulsive disorder (OCD) and autism spectrum disorder (ASD) that impact transporter phosphorylation, cell surface trafficking and/or conformational dynamics. Prior to an initial description of a novel mouse line expressing the non-phosphorylatable SERT substitution Thr276Ala, we review efforts made to elucidate the structure and conformational dynamics of SERT with a focus on research implicating phosphorylation at Thr276 as a determinant of SERT conformational dynamics. Using the high-resolution structure of human SERT in inward- and outward-open conformations, we explore the conformation dependence of SERT Thr276 exposure, with results suggesting that phosphorylation is likely restricted to an inward-open conformation, consistent with prior biochemical studies. Assessment of genotypes from SERT/Ala276 heterozygous matings revealed a deviation from Mendelian expectations, with reduced numbers of Ala276 offspring, though no genotype differences were seen in growth or physical appearance. Similarly, no genotype differences were evident in midbrain or hippocampal 5-HT levels, midbrain and hippocampal SERT mRNA or midbrain protein levels, nor in midbrain synaptosomal 5-HT uptake kinetics. Behaviorally, SERT Ala276 homozygotes appeared normal in measures of anxiety and antidepressant-sensitive stress coping behavior. However, these mice displayed sex-dependent alterations in repetitive and social interactions, consistent with circuit-dependent requirements for Thr276 phosphorylation underlying these behaviors. Our findings indicate the utility of SERT Ala276 mice in evaluation of developmental, functional and behavioral consequences of regulatory SERT phosphorylation in vivo.
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Affiliation(s)
- Carina Meinke
- International Max Planck Research School for Brain and Behavior, Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA.,Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL, USA
| | - Meagan A Quinlan
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL, USA.,Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | | | - Fiona E Harrison
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Cristina Fenollar-Ferrer
- Laboratories of Molecular Genetics and Molecular Biology, National Institute On Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Rania M Katamish
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL, USA
| | - Isabel Stillman
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL, USA
| | | | - Randy D Blakely
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL, USA. .,Florida Atlantic University Brain Institute, Rm 109, MC-17, 5353 Parkside Dr, Jupiter, FL, 35348, USA.
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9
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Phan DH, Shin EJ, Sharma N, Hoang Yen TP, Dang DK, Lee YS, Lee YJ, Nah SY, Cheong JH, Jeong JH, Kim HC. 5-HT 2A receptor-mediated PKCδ phosphorylation is critical for serotonergic impairments induced by p-chloroamphetamine in mice. Food Chem Toxicol 2020; 141:111395. [PMID: 32437895 DOI: 10.1016/j.fct.2020.111395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 04/18/2020] [Accepted: 04/29/2020] [Indexed: 02/06/2023]
Abstract
p-Chloroamphetamine (PCA), an amphetamine derivative, has been shown to induce serotonergic toxicity. However, the precise mechanism of serotonergic toxicity induced by PCA remains unclear. In this study, PCA treatment (20 mg/kg, i.p.) did not significantly change 5-HT1A receptor gene expression, but significantly increased 5-HT2A receptor gene expression. Furthermore, 5-HT2A receptor antagonist MDL11939, but not 5-HT1A receptor antagonist WAY100635, significantly attenuated PCA-induced serotonergic impairments. We investigated whether PCA activated a specific isoform of protein kinase C (PKC), since previous evidence indicated the involvement of PKC in neurotoxicity induced by amphetamines. We observed that PCA treatment significantly increased the expression levels of PKCδ among all PKC isoforms. MDL11939 treatment significantly attenuated PCA-induced phosphorylation of PKCδ. However, PCA-induced increase in 5-HT2A receptor gene expression was not altered by rottlerin (a pharmacological inhibitor of PKCδ) in mice, suggesting that 5-HT2A receptor is an upstream molecule for the activation of PKCδ. Rottlerin or PKCδ knockout significantly attenuated serotonergic behaviors. However, MDL11939 did not show any additional effects against the attenuation caused by PKCδ knockout in mice, suggesting that PKCδ gene is a molecular target for 5-HT2A receptor-mediated serotonergic effects. Our results suggest that 5-HT2A receptor mediates PCA-induced serotonergic impairments via activation of PKC.δ.
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Affiliation(s)
- Dieu Hien Phan
- Neuropsychopharmacology and Toxicology Program, BK21 PLUS Project, College of Pharmacy, Kangwon National University, Chunchon, 24341, Republic of Korea; School of Medicine and Pharmacy - Hoa Quy Ward, The University of Da Nang, Da Nang 550000, Viet Nam
| | - Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, BK21 PLUS Project, College of Pharmacy, Kangwon National University, Chunchon, 24341, Republic of Korea
| | - Naveen Sharma
- Neuropsychopharmacology and Toxicology Program, BK21 PLUS Project, College of Pharmacy, Kangwon National University, Chunchon, 24341, Republic of Korea
| | - Tran Phi Hoang Yen
- Faculty of Pharmacy, University of Medicine and Pharmacy of Ho Chi Minh City, 710000, Viet Nam
| | - Duy-Khanh Dang
- Pharmacy Faculty, Can Tho University of Medicine and Pharmacy, Can Tho City, 900000, Viet Nam
| | - Yong Sup Lee
- Department of Life and Nanopharmaceutical Sciences, College of Pharmacy, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Yu Jeung Lee
- Clinical Pharmacy, College of Pharmacy, Kangwon National University, Chunchon, 24341, Republic of Korea
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory and Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul, 05029, Republic of Korea
| | - Jae Hoon Cheong
- Department of Pharmacy, Sahmyook University, Seoul, 01795, Republic of Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, BK21 PLUS Project, College of Pharmacy, Kangwon National University, Chunchon, 24341, Republic of Korea.
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10
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Shin EJ, Dang DK, Hwang YG, Tran HQ, Sharma N, Jeong JH, Jang CG, Nah SY, Nabeshima T, Yoneda Y, Cadet JL, Kim HC. Significance of protein kinase C in the neuropsychotoxicity induced by methamphetamine-like psychostimulants. Neurochem Int 2019; 124:162-170. [PMID: 30654115 DOI: 10.1016/j.neuint.2019.01.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/27/2018] [Accepted: 01/14/2019] [Indexed: 02/06/2023]
Abstract
The abuse of methamphetamine (MA), an amphetamine (AMPH)-type stimulant, has been demonstrated to be associated with various neuropsychotoxicity, including memory impairment, psychiatric morbidity, and dopaminergic toxicity. Compelling evidence from preclinical studies has indicated that protein kinase C (PKC), a large family of serine/threonine protein kinases, plays an important role in MA-induced neuropsychotoxicity. PKC-mediated N-terminal phosphorylation of dopamine transporter has been identified as one of the prerequisites for MA-induced synaptic dopamine release. Consistently, it has been shown that PKC is involved in MA (or AMPH)-induced memory impairment and mania-like behaviors as well as MA drug dependence. Direct or indirect regulation of factors related to neuronal plasticity seemed to be critical for these actions of PKC. In addition, PKC-mediated mitochondrial dysfunction, oxidative stress or impaired antioxidant defense system has been suggested to play a role in psychiatric and cognitive disturbance induced by MA (or AMPH). In MA-induced dopaminergic toxicity, particularly PKCδ has been shown to trigger oxidative stress, mitochondrial dysfunction, pro-apoptotic changes, and neuroinflammation. Importantly, PKCδ may be a key mediator in the positive feedback loop composed of these detrimental events to potentiate MA-induced dopaminergic toxicity. This review outlines the role of PKC and its individual isozymes in MA-induced neuropsychotoxicity. Better understanding on the molecular mechanism of PKCs might provide a great insight for the development of potential therapeutic or preventive candidates for MA (or AMPH)-associated neuropsychotoxicity.
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Affiliation(s)
- Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Duy-Khanh Dang
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Young Gwang Hwang
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Hai-Quyen Tran
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Naveen Sharma
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Choon-Gon Jang
- Department of Pharmacology, School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory and Department of Physiology, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea
| | - Toshitaka Nabeshima
- Advanced Diagnostic System Research Laboratory, Fujita Health University Graduate School of Health Science, Toyoake 470-1192, Japan
| | - Yukio Yoneda
- Section of Prophylactic Pharmacology, Kanazawa University Venture Business Laboratory, Kanazawa, Ishikawa 920-1192, Japan
| | - Jean Lud Cadet
- NIDA Intramural Program, Molecular Neuropsychiatry Research Branch, 251 Bayview Boulevard, Baltimore, MD 21224, USA
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea.
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11
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Abstract
There is a plethora of amphetamine derivatives exerting stimulant, euphoric, anti-fatigue, and hallucinogenic effects; all structural properties allowing these effects are contained within the amphetamine structure. In the first part of this review, the interaction of amphetamine with the dopamine transporter (DAT), crucially involved in its behavioral effects, is covered, as well as the role of dopamine synthesis, the vesicular monoamine transporter VMAT2, and organic cation 3 transporter (OCT3). The second part deals with requirements in amphetamine's effect on the kinases PKC, CaMKII, and ERK, whereas the third part focuses on where we are in developing anti-amphetamine therapeutics. Thus, treatments are discussed that target DAT, VMAT2, PKC, CaMKII, and OCT3. As is generally true for the development of therapeutics for substance use disorder, there are multiple preclinically promising specific compounds against (meth)amphetamine, for which further development and clinical trials are badly needed.
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Affiliation(s)
- Maarten E A Reith
- Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
| | - Margaret E Gnegy
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, MI, USA
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12
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Yang JW, Larson G, Konrad L, Shetty M, Holy M, Jäntsch K, Kastein M, Heo S, Erdem FA, Lubec G, Vaughan RA, Sitte HH, Foster JD. Dephosphorylation of human dopamine transporter at threonine 48 by protein phosphatase PP1/2A up-regulates transport velocity. J Biol Chem 2018; 294:3419-3431. [PMID: 30587577 DOI: 10.1074/jbc.ra118.005251] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 12/20/2018] [Indexed: 11/06/2022] Open
Abstract
Several protein kinases, including protein kinase C, Ca2+/calmodulin-dependent protein kinase II, and extracellular signal-regulated kinase, play key roles in the regulation of dopamine transporter (DAT) functions. These functions include surface expression, internalization, and forward and reverse transport, with phosphorylation sites for these kinases being linked to distinct regions of the DAT N terminus. Protein phosphatases (PPs) also regulate DAT activity, but the specific residues associated with their activities have not yet been elucidated. In this study, using co-immunoprecipitation followed by MS and immunoblotting analyses, we demonstrate the association of DAT with PP1 and PP2A in the mouse brain and heterologous cell systems. By applying MS in conjunction with a metabolic labeling method, we defined a PP1/2A-sensitive phosphorylation site at Thr-48 in human DAT, a residue that has not been previously reported to be involved in DAT phosphorylation. Site-directed mutagenesis of Thr-48 to Ala (T48A) to prevent phosphorylation enhanced dopamine transport kinetics, supporting a role for this residue in regulating DAT activity. Moreover, T48A-DAT displayed increased palmitoylation, suggesting that phosphorylation/dephosphorylation at this site has an additional regulatory role and reinforcing a previously reported reciprocal relationship between C-terminal palmitoylation and N-terminal phosphorylation.
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Affiliation(s)
- Jae-Won Yang
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - Garret Larson
- the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58202-9037, and
| | - Lisa Konrad
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - Madhur Shetty
- the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58202-9037, and
| | - Marion Holy
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - Kathrin Jäntsch
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - Mirja Kastein
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - Seok Heo
- the Department of Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - Fatma Asli Erdem
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - Gert Lubec
- Paracelsus Medical University of Salzburg, 5020 Salzburg, Austria
| | - Roxanne A Vaughan
- the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58202-9037, and
| | - Harald H Sitte
- From the Institute of Pharmacology, Center for Physiology and Pharmacology, and
| | - James D Foster
- the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58202-9037, and
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13
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Dib T, Martínez-Pinto J, Reyes-Parada M, Torres GE, Sotomayor-Zárate R. Neonatal programming with testosterone propionate reduces dopamine transporter expression in nucleus accumbens and methylphenidate-induced locomotor activity in adult female rats. Behav Brain Res 2018; 346:80-85. [DOI: 10.1016/j.bbr.2017.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/16/2017] [Accepted: 12/01/2017] [Indexed: 12/13/2022]
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14
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Foster JD, Vaughan RA. Phosphorylation mechanisms in dopamine transporter regulation. J Chem Neuroanat 2017; 83-84:10-18. [PMID: 27836487 PMCID: PMC6705611 DOI: 10.1016/j.jchemneu.2016.10.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/26/2016] [Accepted: 10/29/2016] [Indexed: 12/17/2022]
Abstract
The dopamine transporter (DAT) is a plasma membrane phosphoprotein that actively translocates extracellular dopamine (DA) into presynaptic neurons. The transporter is the primary mechanism for control of DA levels and subsequent neurotransmission, and is the target for abused and therapeutic drugs that exert their effects by suppressing reuptake. The transport capacity of DAT is acutely regulated by signaling systems and drug exposure, providing neurons the ability to fine-tune DA clearance in response to specific conditions. Kinase pathways play major roles in these mechanisms, and this review summarizes the current status of DAT phosphorylation characteristics and the evidence linking transporter phosphorylation to control of reuptake and other functions. Greater understanding of these processes may aid in elucidation of their possible contributions to DA disease states and suggest specific phosphorylation sites as targets for therapeutic manipulation of reuptake.
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Affiliation(s)
- James D Foster
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks ND 58202 United States
| | - Roxanne A Vaughan
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks ND 58202 United States.
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15
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Challasivakanaka S, Zhen J, Smith ME, Reith MEA, Foster JD, Vaughan RA. Dopamine transporter phosphorylation site threonine 53 is stimulated by amphetamines and regulates dopamine transport, efflux, and cocaine analog binding. J Biol Chem 2017; 292:19066-19075. [PMID: 28939767 DOI: 10.1074/jbc.m117.787002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 08/29/2017] [Indexed: 11/06/2022] Open
Abstract
The dopamine transporter (DAT) controls the spatial and temporal dynamics of dopamine neurotransmission through reuptake of extracellular transmitter and is a target for addictive compounds such as cocaine, amphetamine (AMPH), and methamphetamine (METH). Reuptake is regulated by kinase pathways and drug exposure, allowing for fine-tuning of clearance in response to specific conditions, and here we examine the impact of transporter ligands on DAT residue Thr-53, a proline-directed phosphorylation site previously implicated in AMPH-stimulated efflux mechanisms. Our findings show that Thr-53 phosphorylation is stimulated in a transporter-dependent manner by AMPH and METH in model cells and rat striatal synaptosomes, and in striatum of rats given subcutaneous injection of METH. Rotating disc electrode voltammetry revealed that initial rates of uptake and AMPH-induced efflux were elevated in phosphorylation-null T53A DAT relative to WT and charge-substituted T53D DATs, consistent with functions related to charge or polarity. These effects occurred without alterations of surface transporter levels, and mutants also showed reduced cocaine analog binding affinity that was not rescued by Zn2+ Together these findings support a role for Thr-53 phosphorylation in regulation of transporter kinetic properties that could impact DAT responses to amphetamines and cocaine.
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Affiliation(s)
- Sathya Challasivakanaka
- From the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201 and
| | | | - Margaret E Smith
- From the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201 and
| | - Maarten E A Reith
- the Departments of Psychiatry and.,Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016
| | - James D Foster
- From the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201 and
| | - Roxanne A Vaughan
- From the Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58201 and
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16
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Carpenter C, Zestos AG, Altshuler R, Sorenson RJ, Guptaroy B, Showalter HD, Kennedy RT, Jutkiewicz E, Gnegy ME. Direct and Systemic Administration of a CNS-Permeant Tamoxifen Analog Reduces Amphetamine-Induced Dopamine Release and Reinforcing Effects. Neuropsychopharmacology 2017; 42:1940-1949. [PMID: 28492278 PMCID: PMC5561350 DOI: 10.1038/npp.2017.95] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 04/29/2017] [Accepted: 05/03/2017] [Indexed: 01/09/2023]
Abstract
Amphetamines (AMPHs) are globally abused. With no effective treatment for AMPH addiction to date, there is urgent need for the identification of druggable targets that mediate the reinforcing action of this stimulant class. AMPH-stimulated dopamine efflux is modulated by protein kinase C (PKC) activation. Inhibition of PKC reduces AMPH-stimulated dopamine efflux and locomotor activity. The only known CNS-permeant PKC inhibitor is the selective estrogen receptor modulator tamoxifen. In this study, we demonstrate that a tamoxifen analog, 6c, which more potently inhibits PKC than tamoxifen but lacks affinity for the estrogen receptor, reduces AMPH-stimulated increases in extracellular dopamine and reinforcement-related behavior. In rat striatal synaptosomes, 6c was almost fivefold more potent at inhibiting AMPH-stimulated dopamine efflux than [3H]dopamine uptake through the dopamine transporter (DAT). The compound did not compete with [3H]WIN 35,428 binding or affect surface DAT levels. Using microdialysis, direct accumbal administration of 1 μM 6c reduced dopamine overflow in freely moving rats. Using LC-MS, we demonstrate that 6c is CNS-permeant. Systemic treatment of rats with 6 mg/kg 6c either simultaneously or 18 h prior to systemic AMPH administration reduced both AMPH-stimulated dopamine overflow and AMPH-induced locomotor effects. Finally, 18 h pretreatment of rats with 6 mg/kg 6c s.c. reduces AMPH-self administration but not food self-administration. These results demonstrate the utility of tamoxifen analogs in reducing AMPH effects on dopamine and reinforcement-related behaviors and suggest a new avenue of development for therapeutics to reduce AMPH abuse.
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Affiliation(s)
- Colleen Carpenter
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - Alexander G Zestos
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Rachel Altshuler
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - Roderick J Sorenson
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA
- Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI, USA
| | - Bipasha Guptaroy
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - Hollis D Showalter
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, USA
- Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI, USA
| | - Robert T Kennedy
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Emily Jutkiewicz
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - Margaret E Gnegy
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
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17
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Rastedt DE, Vaughan RA, Foster JD. Palmitoylation mechanisms in dopamine transporter regulation. J Chem Neuroanat 2017; 83-84:3-9. [PMID: 28115272 DOI: 10.1016/j.jchemneu.2017.01.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 12/21/2016] [Accepted: 01/17/2017] [Indexed: 02/01/2023]
Abstract
The neurotransmitter dopamine (DA) plays a key role in several biological processes including reward, mood, motor activity and attention. Synaptic DA homeostasis is controlled by the dopamine transporter (DAT) which transports extracellular DA into the presynaptic neuron after release and regulates its availability to receptors. Many neurological disorders such as schizophrenia, bipolar disorder, Parkinson disease and attention-deficit hyperactivity disorder are associated with imbalances in DA homeostasis that may be related to DAT dysfunction. DAT is also a target of psychostimulant and therapeutic drugs that inhibit DA reuptake and lead to elevated dopaminergic neurotransmission. We have recently demonstrated the acute and chronic modulation of DA reuptake activity and DAT stability through S-palmitoylation, the linkage of a 16-carbon palmitate group to cysteine via a thioester bond. This review summarizes the properties and regulation of DAT palmitoylation and describes how it serves to affect various transporter functions. Better understanding of the role of palmitoylation in regulation of DAT function may lead to identification of therapeutic targets for modulation of DA homeostasis in the treatment of dopaminergic disorders.
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Affiliation(s)
- Danielle E Rastedt
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States
| | - Roxanne A Vaughan
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States
| | - James D Foster
- Department of Biomedical Sciences, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States.
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18
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Carpenter C, Sorenson RJ, Jin Y, Klossowski S, Cierpicki T, Gnegy M, Showalter HD. Design and synthesis of triarylacrylonitrile analogues of tamoxifen with improved binding selectivity to protein kinase C. Bioorg Med Chem 2016; 24:5495-5504. [PMID: 27647375 DOI: 10.1016/j.bmc.2016.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Revised: 08/30/2016] [Accepted: 09/01/2016] [Indexed: 12/11/2022]
Abstract
The clinical selective estrogen receptor modulator tamoxifen is also a modest inhibitor of protein kinase C, a target implicated in several untreatable brain diseases such as amphetamine abuse. This inhibition and tamoxifen's ability to cross the blood brain barrier make it an attractive scaffold to conduct further SAR studies toward uncovering effective therapies for such diseases. Utilizing the known compound 6a as a starting template and guided by computational tools to derive physicochemical properties known to be important for CNS permeable drugs, the design and synthesis of a small series of novel triarylacrylonitrile analogues have been carried out providing compounds with enhanced potency and selectivity for PKC over the estrogen receptor relative to tamoxifen. Shortened synthetic routes compared to classical procedures have been developed for analogues incorporating a β-phenyl ring, which involve installing dialkylaminoalkoxy side chains first off the α and/or α' rings of a precursor benzophenone and then condensing the resultant ketones with phenylacetonitrile anion. A second novel, efficient and versatile route utilizing Suzuki chemistry has also been developed, which will allow for the introduction of a wide range of β-aryl or β-heteroaryl moieties and side-chain substituents onto the acrylonitrile core. For analogues possessing a single side chain off the α- or α'-ring, novel 2D NMR experiments have been carried out that allow for unambiguous assignment of E- and Z-stereochemistry. From the SAR analysis, one compound, 6c, shows markedly increased potency and selectivity for inhibiting PKC with an IC50 of 80nM for inhibition of PKC protein substrate and >10μM for binding to the estrogen receptor α (tamoxifen IC50=20μM and 222nM, respectively). The data on 6c provide support for further exploration of PKC as a druggable target for the treatment of amphetamine abuse.
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Affiliation(s)
- Colleen Carpenter
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Roderick J Sorenson
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109, United States; Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI 48109, United States
| | - Yafei Jin
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109, United States; Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI 48109, United States
| | - Szymon Klossowski
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Tomasz Cierpicki
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Margaret Gnegy
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, United States
| | - Hollis D Showalter
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109, United States; Vahlteich Medicinal Chemistry Core, University of Michigan, Ann Arbor, MI 48109, United States.
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