1
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Nielsen JC, Salomon K, Kalenderoglou IE, Bargmeyer S, Pape T, Shahsavar A, Loland CJ. Structure of the human dopamine transporter in complex with cocaine. Nature 2024; 632:678-685. [PMID: 39112703 DOI: 10.1038/s41586-024-07804-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 07/09/2024] [Indexed: 08/16/2024]
Abstract
The dopamine transporter (DAT) is crucial for regulating dopamine signalling and is the prime mediator for the rewarding and addictive effects of cocaine1. As part of the neurotransmitter sodium symporter family, DAT uses the Na+ gradient across cell membranes to transport dopamine against its chemical gradient2. The transport mechanism involves both intra- and extracellular gates that control substrate access to a central site. However, the molecular intricacies of this process and the inhibitory mechanism of cocaine have remained unclear. Here, we present the molecular structure of human DAT in complex with cocaine at a resolution of 2.66 Å. Our findings reveal that DAT adopts the expected LeuT-fold, posing in an outward-open conformation with cocaine bound at the central (S1) site. Notably, while an Na+ occupies the second Na+ site (Na2), the Na1 site seems to be vacant, with the side chain of Asn82 occupying the presumed Na+ space. This structural insight elucidates the mechanism for the cocaine inhibition of human DAT and deepens our understanding of neurotransmitter transport. By shedding light on the molecular underpinnings of how cocaine acts, our study lays a foundation for the development of targeted medications to combat addiction.
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Affiliation(s)
- Jeppe C Nielsen
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristine Salomon
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Iris E Kalenderoglou
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sarah Bargmeyer
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tillmann Pape
- Structural Molecular Biology Group, Protein Structure & Function Program, Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Core Facility for Integrated Microscopy (CFIM), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Azadeh Shahsavar
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Claus J Loland
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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2
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Tan J, Xiao Y, Kong F, Zhang X, Xu H, Zhu A, Liu Y, Lei J, Tian B, Yuan Y, Yan C. Molecular basis of human noradrenaline transporter reuptake and inhibition. Nature 2024; 632:921-929. [PMID: 39048818 DOI: 10.1038/s41586-024-07719-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 06/14/2024] [Indexed: 07/27/2024]
Abstract
Noradrenaline, also known as norepinephrine, has a wide range of activities and effects on most brain cell types1. Its reuptake from the synaptic cleft heavily relies on the noradrenaline transporter (NET) located in the presynaptic membrane2. Here we report the cryo-electron microscopy (cryo-EM) structures of the human NET in both its apo state and when bound to substrates or antidepressant drugs, with resolutions ranging from 2.5 Å to 3.5 Å. The two substrates, noradrenaline and dopamine, display a similar binding mode within the central substrate binding site (S1) and within a newly identified extracellular allosteric site (S2). Four distinct antidepressants, namely, atomoxetine, desipramine, bupropion and escitalopram, occupy the S1 site to obstruct substrate transport in distinct conformations. Moreover, a potassium ion was observed within sodium-binding site 1 in the structure of the NET bound to desipramine under the KCl condition. Complemented by structural-guided biochemical analyses, our studies reveal the mechanism of substrate recognition, the alternating access of NET, and elucidate the mode of action of the four antidepressants.
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Affiliation(s)
- Jiaxin Tan
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yuan Xiao
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Fang Kong
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Xiaochun Zhang
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, China
| | - Hanwen Xu
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Angqi Zhu
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yiming Liu
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jianlin Lei
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Boxue Tian
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, China
| | - Yafei Yuan
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.
| | - Chuangye Yan
- Beijing Frontier Research Center for Biological Structure, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.
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3
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Ma S, Damfo S, Bowler MW, Mykhaylyk V, Kozielski F. High-confidence placement of low-occupancy fragments into electron density using the anomalous signal of sulfur and halogen atoms. Acta Crystallogr D Struct Biol 2024; 80:451-463. [PMID: 38841886 PMCID: PMC11154595 DOI: 10.1107/s2059798324004480] [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: 01/02/2024] [Accepted: 05/13/2024] [Indexed: 06/07/2024] Open
Abstract
Fragment-based drug design using X-ray crystallography is a powerful technique to enable the development of new lead compounds, or probe molecules, against biological targets. This study addresses the need to determine fragment binding orientations for low-occupancy fragments with incomplete electron density, an essential step before further development of the molecule. Halogen atoms play multiple roles in drug discovery due to their unique combination of electronegativity, steric effects and hydrophobic properties. Fragments incorporating halogen atoms serve as promising starting points in hit-to-lead development as they often establish halogen bonds with target proteins, potentially enhancing binding affinity and selectivity, as well as counteracting drug resistance. Here, the aim was to unambiguously identify the binding orientations of fragment hits for SARS-CoV-2 nonstructural protein 1 (nsp1) which contain a combination of sulfur and/or chlorine, bromine and iodine substituents. The binding orientations of carefully selected nsp1 analogue hits were focused on by employing their anomalous scattering combined with Pan-Dataset Density Analysis (PanDDA). Anomalous difference Fourier maps derived from the diffraction data collected at both standard and long-wavelength X-rays were compared. The discrepancies observed in the maps of iodine-containing fragments collected at different energies were attributed to site-specific radiation-damage stemming from the strong X-ray absorption of I atoms, which is likely to cause cleavage of the C-I bond. A reliable and effective data-collection strategy to unambiguously determine the binding orientations of low-occupancy fragments containing sulfur and/or halogen atoms while mitigating radiation damage is presented.
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Affiliation(s)
- Shumeng Ma
- School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Shymaa Damfo
- Pharmacognosy and Pharmaceutical Chemistry Department, College of Pharmacy, Taibah University, Al-Madinah Al-Mounawarah 30078, Saudi Arabia
| | | | - Vitaliy Mykhaylyk
- Diamond Light Source, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0DE, United Kingdom
| | - Frank Kozielski
- School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
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4
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Gou R, Yang J, Guo M, Chen Y, Xue W. CNSMolGen: A Bidirectional Recurrent Neural Network-Based Generative Model for De Novo Central Nervous System Drug Design. J Chem Inf Model 2024; 64:4059-4070. [PMID: 38739718 DOI: 10.1021/acs.jcim.4c00504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Central nervous system (CNS) drugs have had a significant impact on treating a wide range of neurodegenerative and psychiatric disorders. In recent years, deep learning-based generative models have shown great potential for accelerating drug discovery and improving efficacy. However, specific applications of these techniques in CNS drug discovery have not been widely reported. In this study, we developed the CNSMolGen model, which uses a framework of bidirectional recurrent neural networks (Bi-RNNs) for de novo molecular design of CNS drugs. Results showed that the pretrained model was able to generate more than 90% of completely new molecular structures, which possessed the properties of CNS drug molecules and were synthesizable. In addition, transfer learning was performed on small data sets with specific biological activities to evaluate the potential application of the model for CNS drug optimization. Here, we used drugs against the classical CNS disease target serotonin transporter (SERT) as a fine-tuned data set and generated a focused database against the target protein. The potential biological activities of the generated molecules were verified by using the physics-based induced-fit docking study. The success of this model demonstrates its potential in CNS drug design and optimization, which provides a new impetus for future CNS drug development.
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Affiliation(s)
- Rongpei Gou
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Jingyi Yang
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Menghan Guo
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Yingjun Chen
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Weiwei Xue
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
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5
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Wu J, Zhang Z, Zhang Q, Li J. Design, synthesis, and biological evaluation of aralkyl piperazine and piperidine derivatives targeting SSRI/5-HT 1A/5-HT 7. Bioorg Med Chem 2024; 104:117698. [PMID: 38552597 DOI: 10.1016/j.bmc.2024.117698] [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: 02/20/2024] [Revised: 03/17/2024] [Accepted: 03/25/2024] [Indexed: 04/20/2024]
Abstract
Serotonin reuptake inhibition combined with the action targeting 5-hydroxytryptamine receptor subtypes can serve as a potential target for the development of antidepressant drugs. Herein a series of new aralkyl piperazines and piperidines were designed and synthesized by the structural modifications of the previously discovered aralkyl piperidine compound 1, targeting SSRI/5-HT1A/5-HT7. The results exhibited that compound 5a showed strong binding to 5-HT1A and 5-HT7 (Ki of 0.46 nM, 2.7 nM, respectively) and a high level of serotonin reuptake inhibition (IC50 of 1.9 nM), all of which were significantly elevated compared to 1. In particular, compound 5a showed weaker inhibitory activity against hERG than 1, and demonstrated good stability in liver microsomes in vitro. The preliminary screening using FST indicated that orally administered 5a, at a high dose, could reduce immobility time in mice markedly, indicating potential antidepressant activity.
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Affiliation(s)
- Jianwei Wu
- Shanghai Institute of Pharmaceutical Industry Co., Ltd., China State Institute of Pharmaceutical Industry, Shanghai 201203, China; National Key Laboratory of Lead Druggability Research, Shanghai Institute of Pharmaceutical Industry Co. Ltd., Shanghai 201203, China
| | - Zixue Zhang
- Shanghai Institute of Pharmaceutical Industry Co., Ltd., China State Institute of Pharmaceutical Industry, Shanghai 201203, China; National Key Laboratory of Lead Druggability Research, Shanghai Institute of Pharmaceutical Industry Co. Ltd., Shanghai 201203, China
| | - Qingwei Zhang
- Shanghai Institute of Pharmaceutical Industry Co., Ltd., China State Institute of Pharmaceutical Industry, Shanghai 201203, China; National Key Laboratory of Lead Druggability Research, Shanghai Institute of Pharmaceutical Industry Co. Ltd., Shanghai 201203, China; School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Jianqi Li
- Shanghai Institute of Pharmaceutical Industry Co., Ltd., China State Institute of Pharmaceutical Industry, Shanghai 201203, China; National Key Laboratory of Lead Druggability Research, Shanghai Institute of Pharmaceutical Industry Co. Ltd., Shanghai 201203, China.
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6
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Galetin A, Brouwer KLR, Tweedie D, Yoshida K, Sjöstedt N, Aleksunes L, Chu X, Evers R, Hafey MJ, Lai Y, Matsson P, Riselli A, Shen H, Sparreboom A, Varma MVS, Yang J, Yang X, Yee SW, Zamek-Gliszczynski MJ, Zhang L, Giacomini KM. Membrane transporters in drug development and as determinants of precision medicine. Nat Rev Drug Discov 2024; 23:255-280. [PMID: 38267543 PMCID: PMC11464068 DOI: 10.1038/s41573-023-00877-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/12/2023] [Indexed: 01/26/2024]
Abstract
The effect of membrane transporters on drug disposition, efficacy and safety is now well recognized. Since the initial publication from the International Transporter Consortium, significant progress has been made in understanding the roles and functions of transporters, as well as in the development of tools and models to assess and predict transporter-mediated activity, toxicity and drug-drug interactions (DDIs). Notable advances include an increased understanding of the effects of intrinsic and extrinsic factors on transporter activity, the application of physiologically based pharmacokinetic modelling in predicting transporter-mediated drug disposition, the identification of endogenous biomarkers to assess transporter-mediated DDIs and the determination of the cryogenic electron microscopy structures of SLC and ABC transporters. This article provides an overview of these key developments, highlighting unanswered questions, regulatory considerations and future directions.
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Affiliation(s)
- Aleksandra Galetin
- Centre for Applied Pharmacokinetic Research, School of Health Sciences, The University of Manchester, Manchester, UK.
| | - Kim L R Brouwer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Kenta Yoshida
- Clinical Pharmacology, Genentech Research and Early Development, South San Francisco, CA, USA
| | - Noora Sjöstedt
- Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Lauren Aleksunes
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, USA
| | - Xiaoyan Chu
- Department of Pharmacokinetics, Dynamics, Metabolism, and Bioanalytics, Merck & Co., Inc., Rahway, NJ, USA
| | - Raymond Evers
- Preclinical Sciences and Translational Safety, Johnson & Johnson, Janssen Pharmaceuticals, Spring House, PA, USA
| | - Michael J Hafey
- Department of Pharmacokinetics, Dynamics, Metabolism, and Bioanalytics, Merck & Co., Inc., Rahway, NJ, USA
| | - Yurong Lai
- Drug Metabolism, Gilead Sciences Inc., Foster City, CA, USA
| | - Pär Matsson
- Department of Pharmacology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Andrew Riselli
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Hong Shen
- Department of Drug Metabolism and Pharmacokinetics, Bristol Myers Squibb Research and Development, Princeton, NJ, USA
| | - Alex Sparreboom
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, USA
| | - Manthena V S Varma
- Pharmacokinetics, Dynamics and Metabolism, Medicine Design, Worldwide R&D, Pfizer Inc, Groton, CT, USA
| | - Jia Yang
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Xinning Yang
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, USA
| | - Sook Wah Yee
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | | | - Lei Zhang
- Office of Research and Standards, Office of Generic Drugs, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, USA
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA.
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7
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Karagöl T, Karagöl A, Zhang S. Structural bioinformatics studies of serotonin, dopamine and norepinephrine transporters and their AlphaFold2 predicted water-soluble QTY variants and uncovering the natural mutations of L->Q, I->T, F->Y and Q->L, T->I and Y->F. PLoS One 2024; 19:e0300340. [PMID: 38517879 PMCID: PMC10959339 DOI: 10.1371/journal.pone.0300340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Accepted: 02/26/2024] [Indexed: 03/24/2024] Open
Abstract
Monoamine transporters including transporters for serotonin, dopamine, and norepinephrine play key roles in monoaminergic synaptic signaling, involving in the molecular etiology of a wide range of neurological and physiological disorders. Despite being crucial drug targets, the study of transmembrane proteins remains challenging due to their localization within the cell membrane. To address this, we present the structural bioinformatics studies of 7 monoamine transporters and their water-soluble variants designed using the QTY code, by systematically replacing the hydrophobic amino acids leucine (L), valine (V), isoleucine (I) and phenylalanine (F) with hydrophilic amino acids (glutamine (Q), threonine (T) and tyrosine (Y). The resulting QTY variants, despite significant protein transmembrane sequence differences (44.27%-51.85%), showed similar isoelectric points (pI) and molecular weights. While their hydrophobic surfaces significantly reduced, this change resulted in a minimal structural alteration. Quantitatively, Alphafold2 predicted QTY variant structures displayed remarkable similarity with RMSD 0.492Å-1.619Å. Accompanied by the structural similarities of substituted amino acids in the context of 1.5Å electron density maps, our study revealed multiple QTY and reverse QTY variations in genomic databases. We further analyzed their phenotypical and topological characteristics. By extending evolutionary game theory to the molecular foundations of biology, we provided insights into the evolutionary dynamics of chemically distinct alpha-helices, their usage in different chemotherapeutic applications, and open possibilities of diagnostic medicine. Our study rationalizes that QTY variants of monoamine transporters may not only become distinct tools for medical, structural, and evolutionary research, but these transporters may also emerge as contemporary therapeutic targets, providing a new approach to treatment for several conditions.
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Affiliation(s)
- Taner Karagöl
- Istanbul University Istanbul Medical Faculty, Istanbul, Turkey
| | - Alper Karagöl
- Istanbul University Istanbul Medical Faculty, Istanbul, Turkey
| | - Shuguang Zhang
- Laboratory of Molecular Architecture, Media Lab, Massachusetts Institute of Technology, Cambridge, MA, United States of America
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8
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Nguyen H, Cheng MH, Lee JY, Aggarwal S, Mortensen OV, Bahar I. Allosteric modulation of serotonin and dopamine transporters: New insights from computations and experiments. Curr Res Physiol 2024; 7:100125. [PMID: 38836245 PMCID: PMC11148570 DOI: 10.1016/j.crphys.2024.100125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 06/06/2024] Open
Abstract
Human monoamine transporters (MATs) are critical to regulating monoaminergic neurotransmission by translocating their substrates from the synaptic space back into the presynaptic neurons. As such, their primary substrate binding site S1 has been targeted by a wide range of compounds for treating neuropsychiatric and neurodegenerative disorders including depression, ADHD, neuropathic pain, and anxiety disorders. We present here a comparative study of the structural dynamics and ligand-binding properties of two MATs, dopamine transporter (DAT) and serotonin transporter (SERT), with focus on the allosteric modulation of their transport function by drugs or substrates that consistently bind a secondary site S2, proposed to serve as an allosteric site. Our systematic analysis of the conformational space and dynamics of a dataset of 50 structures resolved for DAT and SERT in the presence of one or more ligands/drugs reveals the specific residues playing a consistent role in coordinating the small molecules bound to subsites S2-I and S2-II within S2, such as R476 and Y481 in dDAT and E494, P561, and F556 in hSERT. Further analysis reveals how DAT and SERT differ in their two principal modes of structural changes, PC1 and PC2. Notably, PC1 underlies the transition between outward- and inward-facing states of the transporters as well as their gating; whereas PC2 supports the rearrangements of TM helices near the S2 site. Finally, the examination of cross-correlations between structural elements lining the respective sites S1 and S2 point to the crucial role of coupled motions between TM6a and TM10. In particular, we note the involvement of hSERT residues F335 and G338, and E493-E494-T497 belonging to these two respective helices, in establishing the allosteric communication between S1 and S2. These results help understand the molecular basis of the action of drugs that bind to the S2 site of DAT or SERT. They also provide a basis for designing allosteric modulators that may provide better control of specific interactions and cellular pathways, rather than indiscriminately inhibiting the transporter by targeting its orthosteric site.
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Affiliation(s)
- Hoang Nguyen
- Laufer Center for Physical and Quantitative Biology and, USA
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | | | - Ji Young Lee
- Laufer Center for Physical and Quantitative Biology and, USA
| | - Shaili Aggarwal
- Department of Pharmacology and Physiology, Drexel University School of Medicine, Philadelphia, PA, 19102, USA
| | - Ole Valente Mortensen
- Department of Pharmacology and Physiology, Drexel University School of Medicine, Philadelphia, PA, 19102, USA
| | - Ivet Bahar
- Laufer Center for Physical and Quantitative Biology and, USA
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
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9
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Gradisch R, Schlögl K, Lazzarin E, Niello M, Maier J, Mayer FP, Alves da Silva L, Skopec SMC, Blakely RD, Sitte HH, Mihovilovic MD, Stockner T. Ligand coupling mechanism of the human serotonin transporter differentiates substrates from inhibitors. Nat Commun 2024; 15:417. [PMID: 38195746 PMCID: PMC10776687 DOI: 10.1038/s41467-023-44637-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 12/22/2023] [Indexed: 01/11/2024] Open
Abstract
The presynaptic serotonin transporter (SERT) clears extracellular serotonin following vesicular release to ensure temporal and spatial regulation of serotonergic signalling and neurotransmitter homeostasis. Prescription drugs used to treat neurobehavioral disorders, including depression, anxiety, and obsessive-compulsive disorder, trap SERT by blocking the transport cycle. In contrast, illicit drugs of abuse like amphetamines reverse SERT directionality, causing serotonin efflux. Both processes result in increased extracellular serotonin levels. By combining molecular dynamics simulations with biochemical experiments and using a homologous series of serotonin analogues, we uncovered the coupling mechanism between the substrate and the transporter, which triggers the uptake of serotonin. Free energy analysis showed that only scaffold-bound substrates could initiate SERT occlusion through attractive long-range electrostatic interactions acting on the bundle domain. The associated spatial requirements define substrate and inhibitor properties, enabling additional possibilities for rational drug design approaches.
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Affiliation(s)
- Ralph Gradisch
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
| | - Katharina Schlögl
- TU Wien, Institute of Applied Synthetic Chemistry, Getreidemarkt 9, 1060, Vienna, Austria
| | - Erika Lazzarin
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
| | - Marco Niello
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
- Genetics of Cognition Laboratory, Neuroscience area, Istituto Italiano di Tecnologia, via Morego, 30, 16163, Genova, Italy
| | - Julian Maier
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
| | - Felix P Mayer
- Florida Atlantic University, Department of Biomedical Science, Jupiter, FL, 33458, USA
- Stiles-Nicholson Brain Institute, Jupiter, FL, 33458, USA
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Leticia Alves da Silva
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
| | - Sophie M C Skopec
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
| | - Randy D Blakely
- Florida Atlantic University, Department of Biomedical Science, Jupiter, FL, 33458, USA
- Stiles-Nicholson Brain Institute, Jupiter, FL, 33458, USA
| | - Harald H Sitte
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria
- Al-Ahliyya Amman University, Hourani Center for Applied Scientific Research, Amman, Jordan
- Medical University of Vienna, Center for Addiction Research and Science, Waehringer Straße 13A, 1090, Vienna, Austria
| | - Marko D Mihovilovic
- TU Wien, Institute of Applied Synthetic Chemistry, Getreidemarkt 9, 1060, Vienna, Austria
| | - Thomas Stockner
- Medical University of Vienna, Institute of Physiology and Pharmacology, Waehringer Straße 13A, 1090, Vienna, Austria.
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10
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Delpire E, Terker AS, Gagnon KB. Pharmacology of Compounds Targeting Cation-Chloride Cotransporter Physiology. Handb Exp Pharmacol 2024; 283:249-284. [PMID: 37563251 PMCID: PMC10823342 DOI: 10.1007/164_2023_692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Transporters of the solute carrier family 12 (SLC12) carry inorganic cations such as Na+ and/or K+ alongside Cl across the plasma membrane of cells. These tightly coupled, electroneutral, transporters are expressed in almost all tissues/organs in the body where they fulfil many critical functions. The family includes two key transporters participating in salt reabsorption in the kidney: the Na-K-2Cl cotransporter-2 (NKCC2), expressed in the loop of Henle, and the Na-Cl cotransporter (NCC), expressed in the distal convoluted tubule. NCC and NKCC2 are the targets of thiazides and "loop" diuretics, respectively, drugs that are widely used in clinical medicine to treat hypertension and edema. Bumetanide, in addition to its effect as a loop diuretic, has recently received increasing attention as a possible therapeutic agent for neurodevelopmental disorders. This chapter also describes how over the past two decades, the pharmacology of Na+ independent transporters has expanded significantly to provide novel tools for research. This work has indeed led to the identification of compounds that are 100-fold to 1000-fold more potent than furosemide, the first described inhibitor of K-Cl cotransport, and identified compounds that possibly directly stimulate the function of the K-Cl cotransporter. Finally, the recent cryo-electron microscopy revolution has begun providing answers as to where and how pharmacological agents bind to and affect the function of the transporters.
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Affiliation(s)
- Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN, USA.
| | - Andrew S Terker
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Kenneth B Gagnon
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
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11
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Fu T, Zeng S, Zheng Q, Zhu F. The Important Role of Transporter Structures in Drug Disposition, Efficacy, and Toxicity. Drug Metab Dispos 2023; 51:1316-1323. [PMID: 37295948 DOI: 10.1124/dmd.123.001275] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 05/27/2023] [Accepted: 06/02/2023] [Indexed: 06/12/2023] Open
Abstract
The ATP-binding cassette (ABC) and solute carrier (SLC) transporters are critical determinants of drug disposition, clinical efficacy, and toxicity as they specifically mediate the influx and efflux of various substrates and drugs. ABC transporters can modulate the pharmacokinetics of many drugs via mediating the translocation of drugs across biologic membranes. SLC transporters are important drug targets involved in the uptake of a broad range of compounds across the membrane. However, high-resolution experimental structures have been reported for a very limited number of transporters, which limits the study of their physiologic functions. In this review, we collected structural information on ABC and SLC transporters and described the application of computational methods in structure prediction. Taking P-glycoprotein (ABCB1) and serotonin transporter (SLC6A4) as examples, we assessed the pivotal role of structure in transport mechanisms, details of ligand-receptor interactions, drug selectivity, the molecular mechanisms of drug-drug interactions, and differences caused by genetic polymorphisms. The data collected contributes toward safer and more effective pharmacological treatments. SIGNIFICANCE STATEMENT: The experimental structure of ATP-binding cassette and solute carrier transporters was collected, and the application of computational methods in structure prediction was described. P-glycoprotein and serotonin transporter were used as examples to reveal the pivotal role of structure in transport mechanisms, drug selectivity, the molecular mechanisms of drug-drug interactions, and differences caused by genetic polymorphisms.
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Affiliation(s)
- Tingting Fu
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, China (F.Z.); School of Pharmaceutical Sciences, Jilin University, Changchun, China (T.F., Q.Z.); College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China (S.Z., F.Z.); and Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou, China (F.Z.)
| | - Su Zeng
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, China (F.Z.); School of Pharmaceutical Sciences, Jilin University, Changchun, China (T.F., Q.Z.); College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China (S.Z., F.Z.); and Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou, China (F.Z.)
| | - Qingchuan Zheng
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, China (F.Z.); School of Pharmaceutical Sciences, Jilin University, Changchun, China (T.F., Q.Z.); College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China (S.Z., F.Z.); and Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou, China (F.Z.)
| | - Feng Zhu
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, China (F.Z.); School of Pharmaceutical Sciences, Jilin University, Changchun, China (T.F., Q.Z.); College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China (S.Z., F.Z.); and Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou, China (F.Z.)
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12
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Zantza I, Pyrris Y, Raniolo S, Papadaki GF, Lambrinidis G, Limongelli V, Diallinas G, Mikros E. Uracil/H + Symport by FurE Refines Aspects of the Rocking-bundle Mechanism of APC-type Transporters. J Mol Biol 2023; 435:168226. [PMID: 37544358 DOI: 10.1016/j.jmb.2023.168226] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/22/2023] [Accepted: 07/31/2023] [Indexed: 08/08/2023]
Abstract
Transporters mediate the uptake of solutes, metabolites and drugs across the cell membrane. The eukaryotic FurE nucleobase/H+ symporter of Aspergillus nidulans has been used as a model protein to address structure-function relationships in the APC transporter superfamily, members of which are characterized by the LeuT-fold and seem to operate by the so-called 'rocking-bundle' mechanism. In this study, we reveal the binding mode, translocation and release pathway of uracil/H+ by FurE using path collective variable, funnel metadynamics and rational mutational analysis. Our study reveals a stepwise, induced-fit, mechanism of ordered sequential transport of proton and uracil, which in turn suggests that FurE, functions as a multi-step gated pore, rather than employing 'rocking' of compact domains, as often proposed for APC transporters. Finally, our work supports that specific residues of the cytoplasmic N-tail are involved in substrate translocation, in line with their essentiality for FurE function.
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Affiliation(s)
- Iliana Zantza
- Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece.
| | - Yiannis Pyrris
- Department of Biology, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15781, Greece.
| | - Stefano Raniolo
- Faculty of Biomedical Sciences, Euler Institute, Università della Svizzera italiana (USI), Lugano 6900, Switzerland.
| | - Georgia F Papadaki
- Department of Biology, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15781, Greece
| | - George Lambrinidis
- Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece.
| | - Vittorio Limongelli
- Faculty of Biomedical Sciences, Euler Institute, Università della Svizzera italiana (USI), Lugano 6900, Switzerland; Department of Pharmacy, University of Naples "Federico II", Naples 80131, Italy.
| | - George Diallinas
- Department of Biology, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15781, Greece; Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion 70013, Greece.
| | - Emmanuel Mikros
- Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece; Athena Research and Innovation Center in Information Communication & Knowledge Technologies, Marousi 15125, Greece.
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13
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Zhang L, Xu J, Guo J, Wang Y, Wang Q. Elucidation of Pharmacological Mechanism Underlying the Anti-Alzheimer's Disease Effects of Evodia rutaecarpa and Discovery of Novel Lead Molecules: An In Silico Study. Molecules 2023; 28:5846. [PMID: 37570816 PMCID: PMC10421504 DOI: 10.3390/molecules28155846] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/29/2023] [Accepted: 07/20/2023] [Indexed: 08/13/2023] Open
Abstract
Alzheimer's disease (AD) is a brain disease with a peculiarity of multiformity and an insidious onset. Multiple-target drugs, especially Chinese traditional medicine, have achieved a measure of success in AD treatment. Evodia rutaecarpa (Juss.) Benth. (Wuzhuyu, WZY, i.e., E. rutaecarpa), a traditional Chinese herb, has been identified as an effective drug to cure migraines. To our surprise, our in silico study showed that rather than migraines, Alzheimer's disease was the primary disease to which the E. rutaecarpa active compounds were targeted. Correspondingly, a behavioral experiment showed that E. rutaecarpa extract could improve impairments in learning and memory in AD model mice. However, the mechanism underlying the way that E. rutaecarpa compounds target AD is still not clear. For this purpose, we employed methods of pharmacology networking and molecular docking to explore this mechanism. We found that E. rutaecarpa showed significant AD-targeting characteristics, and alkaloids of E. rutaecarpa played the main role in binding to the key nodes of AD. Our research detected that E. rutaecarpa affects the pathologic development of AD through the serotonergic synapse signaling pathway (SLC6A4), hormones (PTGS2, ESR1, AR), anti-neuroinflammation (SRC, TNF, NOS3), transcription regulation (NR3C1), and molecular chaperones (HSP90AA1), especially in the key nodes of PTGS2, AR, SLCA64, and SRC. Graveoline, 5-methoxy-N, N-dimethyltryptamine, dehydroevodiamine, and goshuyuamide II in E. rutaecarpa show stronger binding affinities to these key proteins than currently known preclinical and clinical drugs, showing a great potential to be developed as lead molecules for treating AD.
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Affiliation(s)
- Lulu Zhang
- State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai 200032, China;
| | - Jia Xu
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo 315211, China; (J.X.); (J.G.)
| | - Jiejie Guo
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo 315211, China; (J.X.); (J.G.)
| | - Yun Wang
- State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai 200032, China;
| | - Qinwen Wang
- Ningbo Key Laboratory of Behavioral Neuroscience, Zhejiang Provincial Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo 315211, China; (J.X.); (J.G.)
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14
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Nasiri A, Granberry D, Bepler T. Unsupervised Particle Picking and Clustering in Cryo-EM Micrographs. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:965-966. [PMID: 37613696 DOI: 10.1093/micmic/ozad067.482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Alireza Nasiri
- Simons Machine Learning Center, New York Structural Biology Center, New York, NY, United States
| | - Darnell Granberry
- Simons Machine Learning Center, New York Structural Biology Center, New York, NY, United States
| | - Tristan Bepler
- Simons Machine Learning Center, New York Structural Biology Center, New York, NY, United States
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15
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Yang D, Zhao Z, Tajkhorshid E, Gouaux E. Structures and membrane interactions of native serotonin transporter in complexes with psychostimulants. Proc Natl Acad Sci U S A 2023; 120:e2304602120. [PMID: 37436958 PMCID: PMC10629533 DOI: 10.1073/pnas.2304602120] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/03/2023] [Indexed: 07/14/2023] Open
Abstract
The serotonin transporter (SERT) is a member of the SLC6 neurotransmitter transporter family that mediates serotonin reuptake at presynaptic nerve terminals. SERT is the target of both therapeutic antidepressant drugs and psychostimulant substances such as cocaine and methamphetamines, which are small molecules that perturb normal serotonergic transmission by interfering with serotonin transport. Despite decades of studies, important functional aspects of SERT such as the oligomerization state of native SERT and its interactions with potential proteins remain unresolved. Here, we develop methods to isolate SERT from porcine brain (pSERT) using a mild, nonionic detergent, utilize fluorescence-detection size-exclusion chromatography to investigate its oligomerization state and interactions with other proteins, and employ single-particle cryo-electron microscopy to elucidate the structures of pSERT in complexes with methamphetamine or cocaine, providing structural insights into psychostimulant recognition and accompanying pSERT conformations. Methamphetamine and cocaine both bind to the central site, stabilizing the transporter in an outward open conformation. We also identify densities attributable to multiple cholesterol or cholesteryl hemisuccinate (CHS) molecules, as well as to a detergent molecule bound to the pSERT allosteric site. Under our conditions of isolation, we find that pSERT is best described as a monomeric entity, isolated without interacting proteins, and is ensconced by multiple cholesterol or CHS molecules.
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Affiliation(s)
- Dongxue Yang
- Vollum Institute, Oregon Health and Science University, Portland, OR97239
| | - Zhiyu Zhao
- Department of Biochemistry, NIH Center for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL61801
| | - Emad Tajkhorshid
- Department of Biochemistry, NIH Center for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL61801
| | - Eric Gouaux
- Vollum Institute, Oregon Health and Science University, Portland, OR97239
- HHMI, Oregon Health and Science University, Portland, OR97239
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16
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Barry SCL, Franke C, Mulaudzi T, Pokpas K, Ajayi RF. Review on Surface-Modified Electrodes for the Enhanced Electrochemical Detection of Selective Serotonin Reuptake Inhibitors (SSRIs). MICROMACHINES 2023; 14:1334. [PMID: 37512646 PMCID: PMC10386609 DOI: 10.3390/mi14071334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/19/2023] [Accepted: 06/22/2023] [Indexed: 07/30/2023]
Abstract
Selective serotonin re-uptake inhibitors (SSRIs) are one of the most commonly prescribed classes of antidepressants used for the treatment of moderate to severe depressive disorder, personality disorders and various phobias. This class of antidepressants was created with improved margins of safety. However, genetic polymorphism may be responsible for the high variability in patients' responses to treatment, ranging from failure to delayed therapeutic responses to severe adverse effects of treatment. It is crucial that the appropriate amount of SSRI drugs is administered to ensure the optimum therapeutic efficacy and intervention to minimise severe and toxic effects in patients, which may be the result of accidental and deliberate cases of poisoning. Determining SSRI concentration in human fluids and the environment with high sensitivity, specificity and reproducibility, and at a low cost and real-time monitoring, is imperative. Electrochemical sensors with advanced functional materials have drawn the attention of researchers as a result of these advantages over conventional techniques. This review article aims to present functional materials such as polymers, carbon nanomaterials, metal nanomaterials as well as composites for surface modification of electrodes for sensitive detection and quantification of SSRIs, including fluoxetine, citalopram, paroxetine, fluvoxamine and sertraline. Sensor fabrication, sensor/analyte interactions, design rationale and properties of functional material and the electrocatalytic effect of the modified electrode on SSRI detection are discussed.
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Affiliation(s)
- Simone C L Barry
- SensorLab Laboratories, Chemistry Department, University of the Western Cape, Bellville 7535, South Africa
| | - Candice Franke
- SensorLab Laboratories, Chemistry Department, University of the Western Cape, Bellville 7535, South Africa
| | - Takalani Mulaudzi
- Biotechnology Department, Life Sciences Building, University of the Western Cape, Bellville 7535, South Africa
| | - Keagan Pokpas
- SensorLab Laboratories, Chemistry Department, University of the Western Cape, Bellville 7535, South Africa
| | - Rachel Fanelwa Ajayi
- SensorLab Laboratories, Chemistry Department, University of the Western Cape, Bellville 7535, South Africa
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17
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Rudra S, Omar Faruque M, Tahamina A, Uddin Emon N, Khalil Al Haidar I, Bokhtear Uddin S. Neuropharmacological and antiproliferative activity of Tetrastigma leucostaphyllum (Dennst.) Alston: Evidence from in-vivo, in-vitro and in-silico approaches. Saudi Pharm J 2023; 31:929-941. [PMID: 37234345 PMCID: PMC10205772 DOI: 10.1016/j.jsps.2023.04.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 04/26/2023] [Indexed: 05/27/2023] Open
Abstract
As the incidence of neurodegeneration and cancer fatalities remains high, researchers are focusing their efforts on discovering and developing effective medications, especially plant-based drugs, against these diseases. Hence, this research aimed to investigate the neuropharmacological potentials of aerial parts of Tetrastigma leucostaphyllum, employing some behavioral models, while the antiproliferative effect was explored against a panel of cancer cell lines (MGC-803, A549, U-251, HeLa and MCF-7) using a colorimetric assay. In addition, active extracts were analyzed by GC-MS technique to identify the active compounds, where some selective compounds were docked with the particular pure proteins to check their binding affinity. Results from neuropharmacological research indicated that the total extract and its fractions may be effective (p = 0.05, 0.01, and 0.001, respectively) at doses of 100, 200, and 400 mg/kg of animal body weight. The greatest antidepressant and anxiolytic effects were found in the n-hexane fraction. The n-haxane fraction also exhibited the highest cytotoxicity against the U-251 cell line (IC5014.3 μg/mL), followed by the A549, MG-803, HeLa, and MCF-7 cell lines, respectively. From the n-hexane fraction, ten chemicals were detected using the GC-MS method. Additionally, the in-silico research revealed interactions between the n-hexane fractions' identified compounds and the antidepressant, anxiolytic, and cytotoxic receptors. The molecules showed binding affinities that ranged from 4.6 kcal/mol to 6.8 kcal/mol, which indicates the likelihood that they would make good drug candidates. This study highlighted the plant's neuropharmacological and cytotoxic properties, however, more research is needed to determine the etymological origin of these effects.
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Affiliation(s)
- Sajib Rudra
- Ethnobotany and Pharmacognosy Lab, Department of Botany, University of Chittagong, Chattogram 4331, Bangladesh
| | - Mohammad Omar Faruque
- Ethnobotany and Pharmacognosy Lab, Department of Botany, University of Chittagong, Chattogram 4331, Bangladesh
| | - Afroza Tahamina
- Ethnobotany and Pharmacognosy Lab, Department of Botany, University of Chittagong, Chattogram 4331, Bangladesh
| | - Nazim Uddin Emon
- Department of Pharmacy, Faculty of Science and Engineering, International Islamic University Chittagong, Chattogram 4318, Bangladesh
| | | | - Shaikh Bokhtear Uddin
- Ethnobotany and Pharmacognosy Lab, Department of Botany, University of Chittagong, Chattogram 4331, Bangladesh
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18
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Chopra A, Bauman JD, Ruiz FX, Arnold E. Halo Library, a Tool for Rapid Identification of Ligand Binding Sites on Proteins Using Crystallographic Fragment Screening. J Med Chem 2023; 66:6013-6024. [PMID: 37115705 PMCID: PMC10184123 DOI: 10.1021/acs.jmedchem.2c01681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
X-ray crystallographic fragment screening (XCFS) uses fragment-sized molecules (∼60 to 300 Da) to access binding sites on proteins that may be inaccessible to larger drug-like molecules (>300 Da). Previous studies have shown that fragments containing halogen atoms bind more often to proteins than non-halogenated fragments. Here, we designed the Halo Library containing 46 halogenated fragments (including the "universal fragment" 4-bromopyrazole), a majority of which have been reported to bind to or inhibit one or more targets. The library was screened against the crystals of HIV-1 reverse transcriptase with the drug rilpivirine, yielding an overall hit rate of 26%. Two new binding sites were discovered, and several hot spots were identified. This small library may thus provide a convenient tool for rapidly assessing the feasibility of a target for XCFS, mapping hot spots and cryptic sites, as well as finding fragment binders that can be useful for developing drug leads.
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Affiliation(s)
- Ashima Chopra
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey 08854, United States
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Joseph D Bauman
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey 08854, United States
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Francesc X Ruiz
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey 08854, United States
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Eddy Arnold
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey 08854, United States
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
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19
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Stary D, Bajda M. Taurine and Creatine Transporters as Potential Drug Targets in Cancer Therapy. Int J Mol Sci 2023; 24:ijms24043788. [PMID: 36835201 PMCID: PMC9964810 DOI: 10.3390/ijms24043788] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 02/07/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
Cancer cells are characterized by uncontrolled growth, proliferation, and impaired apoptosis. Tumour progression could be related to poor prognosis and due to this fact, researchers have been working on novel therapeutic strategies and antineoplastic agents. It is known that altered expression and function of solute carrier proteins from the SLC6 family could be associated with severe diseases, including cancers. These proteins were noticed to play important physiological roles through transferring nutrient amino acids, osmolytes, neurotransmitters, and ions, and many of them are necessary for survival of the cells. Herein, we present the potential role of taurine (SLC6A6) and creatine (SLC6A8) transporters in cancer development as well as therapeutic potential of their inhibitors. Experimental data indicate that overexpression of analyzed proteins could be connected with colon or breast cancers, which are the most common types of cancers. The pool of known inhibitors of these transporters is limited; however, one ligand of SLC6A8 protein is currently tested in the first phase of clinical trials. Therefore, we also highlight structural aspects useful for ligand development. In this review, we discuss SLC6A6 and SLC6A8 transporters as potential biological targets for anticancer agents.
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Affiliation(s)
- Dorota Stary
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688 Cracow, Poland
- Doctoral School of Medical and Health Sciences, Jagiellonian University Medical College, św. Łazarza 16 St., 31-530 Cracow, Poland
| | - Marek Bajda
- Department of Physicochemical Drug Analysis, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688 Cracow, Poland
- Correspondence:
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20
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Saikia Q, Hazarika A, Kalita JC. Isoliquiritigenin ameliorates paroxetine-induced sexual dysfunction in male albino mice. Reprod Toxicol 2023; 117:108341. [PMID: 36740106 DOI: 10.1016/j.reprotox.2023.108341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 01/28/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023]
Abstract
Paroxetine (PRX), a widely prescribed antidepressant, often leads to sexual dysfunction. The available management options such as sildenafil (SDF), are associated with side effects. The present study investigates the fertility-boosting properties of isoliquiritigenin (ISL) on PRX-induced sexual dysfunction in male mice. We allocated fertile mice into six different groups (n = 5): group I- DMSO; group II- PRX; group III- co-administered PRX and SDF; group IV- ISL alone; group V- co-administered PRX and ISL (low dose); and, group VI- co-administered PRX and ISL (high dose). 14 days post treatment, animals were sacrificed, and the weights of the testis and epididymis were evaluated. Furthermore, sperm parameters, testicular and epididymal antioxidant levels, serum testosterone and nitric oxide (NO) levels, histoarchitecture of testis and epididymis, and markers of cellular toxicity were assessed. Results revealed that the PRX administration reduced organ weights, sperm count, intact acrosome, catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), serum testosterone, and NO levels, and increased sperm abnormalities and MDA levels (a biomarker for lipid peroxidation). Additionally, we observed damage in the testis and epididymis. The toxicity biomarker study revealed a higher concentration of SGOT, SGPT, and ALP enzymes in the PRX-treated group. However, the co-administration of PRX with ISL ameliorated the adverse effect of PRX on the parameters mentioned above. The PRX+ISL (high) results were almost at par with the PRX+SDF group. The group that received ISL alone showed overall improvements. In conclusion, our comprehensive panel of tests indicates that ISL could be helpful in managing sexual dysfunction.
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Affiliation(s)
- Queen Saikia
- Department of Zoology, Gauhati University, Guwahati, Assam, India.
| | - Ajit Hazarika
- Tyagbir Hem Baruah College, Jamugurihat, Sonitpur, Assam, India
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21
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The Bright Side of Psychedelics: Latest Advances and Challenges in Neuropharmacology. Int J Mol Sci 2023; 24:ijms24021329. [PMID: 36674849 PMCID: PMC9865175 DOI: 10.3390/ijms24021329] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 12/31/2022] [Accepted: 01/05/2023] [Indexed: 01/12/2023] Open
Abstract
The need to identify effective therapies for the treatment of psychiatric disorders is a particularly important issue in modern societies. In addition, difficulties in finding new drugs have led pharmacologists to review and re-evaluate some past molecules, including psychedelics. For several years there has been growing interest among psychotherapists in psilocybin or lysergic acid diethylamide for the treatment of obsessive-compulsive disorder, of depression, or of post-traumatic stress disorder, although results are not always clear and definitive. In fact, the mechanisms of action of psychedelics are not yet fully understood and some molecular aspects have yet to be well defined. Thus, this review aims to summarize the ethnobotanical uses of the best-known psychedelic plants and the pharmacological mechanisms of the main active ingredients they contain. Furthermore, an up-to-date overview of structural and computational studies performed to evaluate the affinity and binding modes to biologically relevant receptors of ibogaine, mescaline, N,N-dimethyltryptamine, psilocin, and lysergic acid diethylamide is presented. Finally, the most recent clinical studies evaluating the efficacy of psychedelic molecules in some psychiatric disorders are discussed and compared with drugs already used in therapy.
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22
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Horowitz MA, Framer A, Hengartner MP, Sørensen A, Taylor D. Estimating Risk of Antidepressant Withdrawal from a Review of Published Data. CNS Drugs 2023; 37:143-157. [PMID: 36513909 PMCID: PMC9911477 DOI: 10.1007/s40263-022-00960-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/20/2022] [Indexed: 12/15/2022]
Abstract
Adaptation of the brain to the presence of a drug predicts withdrawal on cessation. The outcome of adaptation is often referred to as 'physical dependence' in pharmacology, as distinct from addiction, although these terms have unfortunately become conflated in some diagnostic guides. Physical dependence to antidepressants may occur in some patients, consistent with the fact that some patients experience withdrawal effects from these medications. It is thought that longer duration of use, higher dose and specific antidepressants affect the risk of antidepressant withdrawal effects as they might cause greater adaptation of the brain. We searched PubMed for relevant systematic reviews and other relevant analyses to summarise existing data on determinants of antidepressant withdrawal incidence, severity and duration. Overall, data were limited. From survey data, increased duration of use was associated with an increased incidence and severity of withdrawal effects, consistent with some evidence from data provided by drug manufacturers. Duration of use may be related to duration of withdrawal effects but data are heterogenous and sparse. Serotonin and noradrenaline reuptake inhibitors and paroxetine are associated with higher risks than other antidepressants, though data for some antidepressants are lacking. Higher doses of antidepressant has some weak association with an increased risk of withdrawal, with some ceiling effects, perhaps reflecting receptor occupancy relationships. Past experience of withdrawal effects is known to predict future risk. Based on these data, we outline a preliminary rubric for determining the risk of withdrawal symptoms for a particular patient, which may have relevance for determining tapering rates. Given the limited scope of the current research, future research should aim to clarify prediction of antidepressant withdrawal risk, especially by examining the risk of withdrawal in long-term users of medication, as well as the severity and duration of effects, to improve the preliminary tool for predictive purposes. Further research into the precise adaptations in long-term antidepressant use may improve the ability to predict withdrawal effects for a particular patient.
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Affiliation(s)
- Mark Abie Horowitz
- North East London NHS Foundation Trust, Goodmayes Hospital, Ilford, UK. .,Division of Psychiatry, University College London (Honorary), Maple House, 149 Tottenham Court Rd, Fitzrovia, London, W1T 7BN, UK.
| | - Adele Framer
- SurvivingAntidepressants.org, San Francisco, CA USA
| | - Michael P. Hengartner
- Department of Applied Psychology, Zurich University of Applied Sciences, Zurich, Switzerland
| | - Anders Sørensen
- Copenhagen Trial Unit, Centre for Clinical Intervention Research, Capital Region of Denmark, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - David Taylor
- South London and Maudsley NHS Foundation Trust, London, UK ,Institute of Pharmaceutical Science, King’s College London, London, UK
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23
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Aggarwal S, Mortensen OV. Discovery and Development of Monoamine Transporter Ligands. ADVANCES IN NEUROBIOLOGY 2023; 30:101-129. [PMID: 36928847 PMCID: PMC10074400 DOI: 10.1007/978-3-031-21054-9_4] [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: 03/18/2023]
Abstract
Monoamine transporters (MATs) are targets of a wide range of compounds that have been developed as therapeutic treatments for various neuropsychiatric and neurodegenerative disorders such as depression, ADHD, neuropathic pain, anxiety disorders, stimulant use disorders, epilepsy, and Parkinson's disease. The MAT family is comprised of three main members - the dopamine transporter (DAT), the norepinephrine transporter (NET), and the serotonin transporter (SERT). These transporters are through reuptake responsible for the clearance of their respective monoamine substrates from the extracellular space. The determination of X-ray crystal structures of MATs and their homologues bound with various substrates and ligands has resulted in a surge of structure-function-based studies of MATs to understand the molecular basis of transport function and the mechanism of various ligands that ultimately result in their behavioral effects. This review focusses on recent examples of ligand-based structure-activity relationship studies trying to overcome some of the challenges associated with previously developed MAT inhibitors. These studies have led to the discovery of unique and novel structurally diverse MAT ligands including allosteric modulators. These novel molecular scaffolds serve as leads for designing more effective therapeutic interventions by modulating the activities of MATs and ultimately their associated neurotransmission and behavioral effects.
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Affiliation(s)
- Shaili Aggarwal
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA, USA.
| | - Ole Valente Mortensen
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA, USA.
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24
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Zhang Y, Zhang J, Wang J, Chen H, Ouyang L, Wang Y. Targeting GRK2 and GRK5 for treating chronic degenerative diseases: Advances and future perspectives. Eur J Med Chem 2022; 243:114668. [DOI: 10.1016/j.ejmech.2022.114668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 11/16/2022]
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25
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Liu H, Wu Y, Li C, Tang Q, Zhang YW. Molecular docking and biochemical validation of (-)-syringaresinol-4-O-β-D-apiofuranosyl-(1→2)-β-D-glucopyranoside binding to an allosteric site in monoamine transporters. Front Pharmacol 2022; 13:1018473. [PMID: 36386236 PMCID: PMC9649612 DOI: 10.3389/fphar.2022.1018473] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 10/17/2022] [Indexed: 06/11/2024] Open
Abstract
Albizia julibrissin Durazz is one of the most common herbs used for depression and anxiety treatment, but its mechanism of action as an antidepressant or anxiolytic drug have not been fully understood. We previously isolated and identified one lignan glycoside compound from Albizia Julibrissin Durazz, (-)-syringaresinol-4-O-β-D-apiofuranosyl-(1→2)-β-D-glucopyranoside (SAG), that inhibited all three monoamine transporters with a mechanism of action different from that of the conventional antidepressants. In this study, we generated homology models for human dopamine transporter and human norepinephrine transporter, based on the X-ray structure of Drosophila dopamine transporter, and conducted the molecular docking of SAG to all three human monoamine transporters. Our computational results indicated that SAG binds to an allosteric site (S2) that has been demonstrated to be formed by an aromatic pocket positioned in the scaffold domain in the extracellular vestibule connected to the central site (S1) in these monoamine transporters. In addition, we demonstrated that SAG stabilizes a conformation of serotonin transporter with both the extracellular and cytoplasmic pathways closed. Furthermore, we performed mutagenesis of the residues in both the allosteric and orthosteric sites to biochemically validate SAG binding in all three monoamine transporters. Our results are consistent with the molecular docking calculation and support the association of SAG with the allosteric site. We expect that this herbal molecule could become a lead compound for the development of new therapeutic agents with a novel mechanism of action.
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Affiliation(s)
- Hanhe Liu
- School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Yingyao Wu
- School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Chan Li
- School of Life Sciences, Guangzhou University, Guangzhou, China
| | - Qingfa Tang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics, Guangzhou, China
| | - Yuan-Wei Zhang
- School of Life Sciences, Guangzhou University, Guangzhou, China
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26
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Wentinck K, Gogou C, Meijer DH. Putting on molecular weight: Enabling cryo-EM structure determination of sub-100-kDa proteins. Curr Res Struct Biol 2022; 4:332-337. [PMID: 36248264 PMCID: PMC9562432 DOI: 10.1016/j.crstbi.2022.09.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/22/2022] [Accepted: 09/25/2022] [Indexed: 11/17/2022] Open
Abstract
Significant advances in the past decade have enabled high-resolution structure determination of a vast variety of proteins by cryogenic electron microscopy single particle analysis. Despite improved sample preparation, next-generation imaging hardware, and advanced single particle analysis algorithms, small proteins remain elusive for reconstruction due to low signal-to-noise and lack of distinctive structural features. Multiple efforts have therefore been directed at the development of size-increase techniques for small proteins. Here we review the latest methods for increasing effective molecular weight of proteins <100 kDa through target protein binding or target protein fusion - specifically by using nanobody-based assemblies, fusion tags, and symmetric scaffolds. Finally, we summarize these state-of-the-art techniques into a decision-tree to facilitate the design of tailored future approaches, and thus for further exploration of ever-smaller proteins that make up the largest part of the human genome.
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Key Words
- BRIL, cytochromeb562 RIL
- DARPin, Design Ankyrin Repeat Protein
- Fab, antigen binding fragment
- GFP, Green Fluorecent Protein
- GPCR, G protein-coupled receptor
- MW, molecular weight
- Mb, megabody
- Nb, nanobody
- SNR, signal-to-noise ratio
- SPA, single particle analysis
- TM, transmembrane
- cryo-EM, cryogenic electron microscopy
- kDa, kiloDalton
- κOR ICL3, κ-opiod receptor intracellular loop 3
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Affiliation(s)
| | | | - Dimphna H. Meijer
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, van der Maasweg 9, 2629HZ, Delft, the Netherlands
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27
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Dunham KE, Venton BJ. SSRI antidepressants differentially modulate serotonin reuptake and release in Drosophila. J Neurochem 2022; 162:404-416. [PMID: 35736504 PMCID: PMC9427694 DOI: 10.1111/jnc.15658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/27/2022] [Accepted: 06/17/2022] [Indexed: 11/26/2022]
Abstract
Selective serotonin reuptake inhibitor (SSRI) antidepressants are commonly prescribed treatments for depression, but their effects on serotonin reuptake and release are not well understood. Drosophila melanogaster, the fruit fly, expresses the serotonin transporter (dSERT), the major target of SSRIs, but real-time serotonin changes after SSRIs have not been characterized in this model. The goal of this study was to characterize effects of SSRIs on serotonin concentration and reuptake in Drosophila larvae. We applied various doses (0.1-100 μM) of fluoxetine (Prozac), escitalopram (Lexapro), citalopram (Celexa), and paroxetine (Paxil), to ventral nerve cord (VNC) tissue and measured optogenetically-stimulated serotonin release with fast-scan cyclic voltammetry (FSCV). Fluoxetine increased reuptake from 1 to 100 μM, but serotonin concentration only increased at 100 μM. Thus, fluoxetine occupies dSERT and slows clearance but does not affect concentration. Escitalopram and paroxetine increased serotonin concentrations at all doses, but escitalopram increased reuptake more. Citalopram showed lower concentration changes and faster reuptake profiles compared with escitalopram, so the racemic mixture of citalopram does not change reuptake as much as the S-isomer. Dose response curves were constructed to compare dSERT affinities and paroxetine showed the highest affinity and fluoxetine the lowest. These data demonstrate SSRI mechanisms are complex, with separate effects on reuptake or release. Furthermore, dynamic serotonin changes in Drosophila are similar to previous studies in mammals. This work establishes how antidepressants affect serotonin in real-time, which is useful for future studies that will investigate pharmacological effects of SSRIs with different genetic mutations in Drosophila.
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Affiliation(s)
- Kelly E Dunham
- Department of Chemistry, University of Virginia, Virginia, USA
| | - B Jill Venton
- Department of Chemistry, University of Virginia, Virginia, USA
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28
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Maphanga VB, Skalicka-Wozniak K, Budzynska B, Skiba A, Chen W, Agoni C, Enslin GM, Viljoen AM. Mesembryanthemum tortuosum L. alkaloids modify anxiety-like behaviour in a zebrafish model. JOURNAL OF ETHNOPHARMACOLOGY 2022; 290:115068. [PMID: 35134486 DOI: 10.1016/j.jep.2022.115068] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 01/29/2022] [Accepted: 01/31/2022] [Indexed: 06/14/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Mesembryanthemum tortuosum L. (previously known as Sceletium tortuosum (L.) N.E. Br.) is indigenous to South Africa and traditionally used to alleviate anxiety, stress and depression. Mesembrine and its alkaloid analogues such as mesembrenone, mesembrenol and mesembranol have been identified as the key compounds responsible for the reported effects on the central nervous system. AIM OF THE STUDY To investigate M. tortuosum alkaloids for possible anxiolytic-like effects in the 5-dpf in vivo zebrafish model by assessing thigmotaxis and locomotor activity. MATERIALS AND METHODS Locomotor activity and reverse-thigmotaxis, recognised anxiety-related behaviours in 5-days post fertilization zebrafish larvae, were analysed under simulated stressful conditions of alternating light-dark challenges. Cheminformatics screening and molecular docking were also performed to rationalize the inhibitory activity of the alkaloids on the serotonin reuptake transporter, the accepted primary mechanism of action of selective serotonin reuptake inhibitors. Mesembrine has been reported to have inhibitory effects on serotonin reuptake, with consequential anti-depressant and anxiolytic effects. RESULTS All four alkaloids assessed decreased the anxiety-related behaviour of zebrafish larvae exposed to the light-dark challenge. Significant increases in the percentage of time spent in the central arena during the dark phase were also observed when larvae were exposed to the pure alkaloids (mesembrenone, mesembrenol, mesembrine and mesembrenol) compared to the control. However, mesembrenone and mesembranol demonstrated a greater anxiolytic-like effect than the other alkaloids. In addition to favourable pharmacokinetic and physicochemical properties revealed via in silico predictions, high-affinity interactions characterized the binding of the alkaloids with the serotonin transporter. CONCLUSIONS M. tortuosum alkaloids demonstrated an anxiolytic-like effect in zebrafish larvae providing evidence for its traditional and modern day use as an anxiolytic.
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Affiliation(s)
- Veronica B Maphanga
- Department of Pharmaceutical Sciences, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa
| | - Krystyna Skalicka-Wozniak
- Department of Natural Products Chemistry, Medical University of Lublin, 1 Chodzki Street, 20-093, Lublin, Poland
| | - Barbara Budzynska
- Behavioral Studies Laboratory, Department of Medicinal Chemistry, Medical University of Lublin, 4A Chodzki Street, 20-093, Lublin, Poland
| | - Andriana Skiba
- Department of Natural Products Chemistry, Medical University of Lublin, 1 Chodzki Street, 20-093, Lublin, Poland
| | - Weiyang Chen
- Department of Pharmaceutical Sciences, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa
| | - Clement Agoni
- Department of Pharmaceutical Sciences, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa
| | - Gill M Enslin
- Department of Pharmaceutical Sciences, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa
| | - Alvaro M Viljoen
- Department of Pharmaceutical Sciences, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, South Africa; SAMRC Herbal Drugs Research Unit, Tshwane University of Technology, Pretoria, 0001, South Africa.
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29
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Huang B, Liu H, Wu Y, Li C, Tang Q, Zhang YW. Two Lignan Glycosides from Albizia julibrissin Durazz. Noncompetitively Inhibit Serotonin Transporter. Pharmaceuticals (Basel) 2022; 15:ph15030344. [PMID: 35337141 PMCID: PMC8954383 DOI: 10.3390/ph15030344] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/07/2022] [Accepted: 03/10/2022] [Indexed: 12/11/2022] Open
Abstract
Albizia julibrissin Durazz. is one of the most common herbs used for depression and anxiety treatment, but its molecular basis and mechanism of action as an antidepressant or anxiolytic drug are not understood. In this study, we separated and identified two lignan glycosides that inhibit serotonin transporter (SERT) noncompetitively by decreasing Vmax with little change in Km for its fluorescence substrate. In addition, treatment with lignan glycosides did not alter total and cell surface expression levels of the transporter protein. The two compounds decreased the accessibility of a cysteine residue placed in the extracellular substrate permeation pathway by inducing a conformational shift toward an outward-closed state of SERT. These results are consistent with molecular docking for the association of the lignan glycosides to the allosteric site in SERT. The present work supports the proposal that these compounds act on SERT by a novel underlying mechanism of action different from that of conventional antidepressant drugs.
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Affiliation(s)
- Bishan Huang
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China; (B.H.); (H.L.); (Y.W.); (C.L.)
| | - Hanhe Liu
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China; (B.H.); (H.L.); (Y.W.); (C.L.)
| | - Yingyao Wu
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China; (B.H.); (H.L.); (Y.W.); (C.L.)
| | - Chan Li
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China; (B.H.); (H.L.); (Y.W.); (C.L.)
| | - Qingfa Tang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China;
- Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics, Guangzhou 510515, China
| | - Yuan-Wei Zhang
- School of Life Sciences, Guangzhou University, Guangzhou 510006, China; (B.H.); (H.L.); (Y.W.); (C.L.)
- Correspondence:
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30
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Piticari A, Antermite D, Higham JI, Moore JH, Webster MP, Bull JA. Stereoselective Palladium‐Catalyzed C(
sp
3
)−H Mono‐Arylation of Piperidines and Tetrahydropyrans with a C(4) Directing Group. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Amalia‐Sofia Piticari
- Department of Chemistry Imperial College London Molecular Sciences Research Hub White City Campus Wood Lane London W12 0BZ UK
| | - Daniele Antermite
- Department of Chemistry Imperial College London Molecular Sciences Research Hub White City Campus Wood Lane London W12 0BZ UK
| | - Joe I. Higham
- Department of Chemistry Imperial College London Molecular Sciences Research Hub White City Campus Wood Lane London W12 0BZ UK
| | - J. Harry Moore
- Department of Chemistry Imperial College London Molecular Sciences Research Hub White City Campus Wood Lane London W12 0BZ UK
| | | | - James A. Bull
- Department of Chemistry Imperial College London Molecular Sciences Research Hub White City Campus Wood Lane London W12 0BZ UK
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31
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What is the mechanism of loudness hyperacusis in autism? Med Hypotheses 2022. [DOI: 10.1016/j.mehy.2021.110759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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Aree T. Inclusion Scenarios and Conformational Flexibility of the SSRI Paroxetine as Perceived from Polymorphism of β-Cyclodextrin–Paroxetine Complex. Pharmaceuticals (Basel) 2022; 15:ph15010098. [PMID: 35056155 PMCID: PMC8781563 DOI: 10.3390/ph15010098] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 02/01/2023] Open
Abstract
Depression, a global mental health problem, is prevalent during the coronavirus disease 2019 (COVID-19) pandemic and can be efficiently treated by selective serotonin reuptake inhibitors (SSRIs). Our study series aims at forwarding insights on the β-cyclodextrin (β-CD)–SSRI inclusion complexes by X-ray crystallography combined with density functional theory (DFT) calculation. Here, we report a new crystal form (II) of the 1:1 β-CD–paroxetine (PXT) complex, which is inspired by the reported 2:1 β-CD–PXT complex (crystal form I), reflecting an elusive phenomenon of the polymorphism in CD inclusion complexes. The β-CD–PXT polymorphism stems from the PXT conformational flexibility, which is defined by torsion angles κ, ε around the -CH2–O- group bridging the A- and C–D-rings, of which those of PXT in I and II are totally different. While PXT (II) in an open V-shaped conformation that has the B-ring shallowly inserted in the β-CD cavity, PXT (I) in a closed U-shaped structure is mostly entirely embedded in the β-CD dimeric cavity, of which the A-ring is deeply inserted in the main β-CD cavity. However, PXT molecules in both crystal forms are similarly maintained in the CD cavity via host–guest N–H···O5/O6 H-bonds and C/O–H···π(B/C) interactions and β-CDs have similar 3D arrangements, channel (II) vs. screw-channel (I). Further theoretical explorations on the β-CD–PXT thermodynamic stabilities and the PXT conformational stabilities based on their potential energy surfaces (PESs) have been completed by DFT calculations. The 2:1 β-CD–PXT complex with the greater presence of dispersion interactions is more energetically favorable than the unimolar complex. Conversely, whereas free PXT, PXT (II) and PXT in complex with serotonin transporter are more energetically stable, PXT (I) is least stable and stabilized in the β-CD cavity. As SSRIs could lessen the COVID-19 severity, the CD inclusion complexation not only helps to improve the drug bioavailability, but also promotes the use of antidepressants and COVID-19 medicines concurrently.
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Affiliation(s)
- Thammarat Aree
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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33
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Nagayasu K. Serotonin transporter: Recent progress of in silico ligand prediction methods and structural biology towards structure-guided in silico design of therapeutic agents. J Pharmacol Sci 2022; 148:295-299. [DOI: 10.1016/j.jphs.2022.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/21/2021] [Accepted: 01/06/2022] [Indexed: 02/08/2023] Open
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Yang D, Gouaux E. Illumination of serotonin transporter mechanism and role of the allosteric site. SCIENCE ADVANCES 2021; 7:eabl3857. [PMID: 34851672 PMCID: PMC8635421 DOI: 10.1126/sciadv.abl3857] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 10/14/2021] [Indexed: 05/10/2023]
Abstract
The serotonin transporter (SERT) terminates serotonin signaling by using sodium and chloride gradients to drive reuptake of serotonin into presynaptic neurons and is the target of widely used medications to treat neuropsychiatric disorders. Despite decades of study, the molecular mechanism of serotonin transport, the coupling to ion gradients, and the role of the allosteric site have remained elusive. Here, we present cryo–electron microscopy structures of SERT in serotonin-bound and serotonin-free states, in the presence of sodium or potassium, resolving all fundamental states of the transport cycle. From the SERT-serotonin complex, we localize the substrate-bound allosteric site, formed by an aromatic pocket positioned in the scaffold domain in the extracellular vestibule, connected to the central site via a short tunnel. Together with elucidation of multiple apo state conformations, we provide previously unseen structural understanding of allosteric modulation, demonstrating how SERT binds serotonin from synaptic volumes and promotes unbinding into the presynaptic neurons.
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Affiliation(s)
- Dongxue Yang
- Vollum Institute, Oregon Health and Science University, Portland, OR 97239, USA
| | - Eric Gouaux
- Vollum Institute, Oregon Health and Science University, Portland, OR 97239, USA
- Howard Hughes Medical Institute, Oregon Health and Science University, Portland, OR 97239, USA
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35
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Steele TWE, Spires Z, Jones CB, Glennon RA, Dukat M, Eltit JM. Non-conserved residues dictate dopamine transporter selectivity for the potent synthetic cathinone and psychostimulant MDPV. Neuropharmacology 2021; 200:108820. [PMID: 34619165 DOI: 10.1016/j.neuropharm.2021.108820] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 08/17/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
Clandestine chemists are currently exploiting the pyrrolidinophenone scaffold to develop new designer drugs that carry the risk of abuse and overdose. These drugs promote addiction through the rewarding effects of increased dopaminergic neurotransmission. 3,4-Methylenedioxypyrovalerone (MDPV) and its analogs are illicit psychostimulants of this class that are ∼50-fold more potent than cocaine at inhibiting the human dopamine transporter (hDAT). In contrast, MDPV is a weak inhibitor at both the human serotonin transporter (hSERT) and, as it is shown here, the Drosophila melanogaster DAT (dDAT). We studied three conserved residues between hSERT and dDAT that are unique in hDAT (A117, F318, and P323 in dDAT), and one residue that is different in all three transporters (D121 in dDAT). hDAT residues were replaced in the dDAT sequence at these positions using site-directed mutagenesis and stable cell lines were generated expressing these mutant transporters. The potencies of MDPV and two of its analogs were determined using a Ca2+-mobilization assay. In this assay, voltage-gated Ca2+ channels are expressed to sense the membrane electrical depolarization evoked when dopamine is transported through DAT. Each individual mutant slightly improved MDPV's potency, but the combination of all four increased its potency ∼100-fold (2 log units) in inhibiting dDAT activity. Molecular modeling and docking studies were conducted to explore the possible mode of interaction between MDPV and DAT in silico. Two of the studied residues (F318 and P323) are at the entrance of the S1 binding site, whereas the other two (A117 and D121) face the aryl moiety of MDPV when bound to this site. Therefore, these four non-conserved residues can influence MDPV selectivity not only by stabilizing binding, but also by controlling access to its binding site at DAT.
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Affiliation(s)
- Tyler W E Steele
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, USA
| | - Zachary Spires
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, USA
| | - Charles B Jones
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, USA
| | - Richard A Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, USA
| | - Małgorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, USA
| | - Jose M Eltit
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, USA.
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36
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Frangos ZJ, Cantwell Chater RP, Vandenberg RJ. Glycine Transporter 2: Mechanism and Allosteric Modulation. Front Mol Biosci 2021; 8:734427. [PMID: 34805268 PMCID: PMC8602798 DOI: 10.3389/fmolb.2021.734427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/25/2021] [Indexed: 01/19/2023] Open
Abstract
Neurotransmitter sodium symporters (NSS) are a subfamily of SLC6 transporters responsible for regulating neurotransmitter signalling. They are a major target for psychoactive substances including antidepressants and drugs of abuse, prompting substantial research into their modulation and structure-function dynamics. Recently, a series of allosteric transport inhibitors have been identified, which may reduce side effect profiles, compared to orthosteric inhibitors. Allosteric inhibitors are also likely to provide different clearance kinetics compared to competitive inhibitors and potentially better clinical outcomes. Crystal structures and homology models have identified several allosteric modulatory sites on NSS including the vestibule allosteric site (VAS), lipid allosteric site (LAS) and cholesterol binding site (CHOL1). Whilst the architecture of eukaryotic NSS is generally well conserved there are differences in regions that form the VAS, LAS, and CHOL1. Here, we describe ligand-protein interactions that stabilize binding in each allosteric site and explore how differences between transporters could be exploited to generate NSS specific compounds with an emphasis on GlyT2 modulation.
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Affiliation(s)
- Zachary J Frangos
- Transporter Biology Group, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Ryan P Cantwell Chater
- Transporter Biology Group, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Robert J Vandenberg
- Transporter Biology Group, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
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Tomlinson ID, Kovtun O, Torres R, Bellocchio LG, Josephs T, Rosenthal SJ. A Novel Biotinylated Homotryptamine Derivative for Quantum Dot Imaging of Serotonin Transporter in Live Cells. Front Cell Neurosci 2021; 15:667044. [PMID: 34867196 PMCID: PMC8637195 DOI: 10.3389/fncel.2021.667044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 10/19/2021] [Indexed: 11/21/2022] Open
Abstract
The serotonin transporter (SERT) is the primary target for selective serotonin reuptake inhibitor (SSRI) antidepressants that are thought to exert their therapeutic effects by increasing the synaptic concentration of serotonin. Consequently, probes that can be utilized to study cellular trafficking of SERT are valuable research tools. We have developed a novel ligand (IDT785) that is composed of a SERT antagonist (a tetrahydro pyridyl indole derivative) conjugated to a biotinylated poly ethylene glycol (PEG) via a phenethyl linker. This compound was determined to be biologically active and inhibited SERT-mediated reuptake of IDT307 with the half-maximal inhibitory concentration of 7.2 ± 0.3 μM. We demonstrated that IDT785 enabled quantum dot (QD) labeling of membrane SERT in transfected HEK-293 cultures that could be blocked using the high affinity serotonin reuptake inhibitor paroxetine. Molecular docking studies suggested that IDT785 might be binding to the extracellular vestibule binding site rather than the orthosteric substrate binding site, which could be attributable to the hydrophilicity of the PEG chain and the increased loss of degrees of freedom that would be required to penetrate into the orthosteric binding site. Using IDT785, we were able to study the membrane localization and membrane dynamics of YFP-SERT heterologously expressed in HEK-293 cells and demonstrated that SERT expression was enriched in the membrane edge and in thin cellular protrusions.
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Affiliation(s)
- Ian D. Tomlinson
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Oleg Kovtun
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Ruben Torres
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, United States
| | | | - Travis Josephs
- Neuroscience Program, Vanderbilt University, Nashville, TN, United States
| | - Sandra J. Rosenthal
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, United States
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, United States
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, United States
- Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University, Nashville, TN, United States
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Jacobson KA, Salmaso V, Suresh RR, Tosh DK. Expanding the repertoire of methanocarba nucleosides from purinergic signaling to diverse targets. RSC Med Chem 2021; 12:1808-1825. [PMID: 34825182 PMCID: PMC8597424 DOI: 10.1039/d1md00167a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/01/2021] [Indexed: 12/11/2022] Open
Abstract
Nucleoside derivatives are well represented as pharmaceuticals due to their druglike physicochemical properties, and some nucleoside drugs are designed to act on receptors. The purinergic signaling pathways for extracellular nucleosides and nucleotides, consisting of adenosine receptors, P2Y/P2X receptors for nucleotides, and enzymes such as adenosine (ribo)kinase, have been extensively studied. A general modification, i.e. a constrained, bicyclic ring system (bicyclo[3.1.0]hexane, also called methanocarba) substituted in place of a furanose ring, can increase nucleoside/nucleotide potency and/or selectivity at purinergic and antiviral targets and in interactions at diverse and unconventional targets. Compared to other common drug discovery scaffolds containing planar rings, methanocarba nucleosides display greater sp3 character (i.e. more favorable as drug-like molecules) and can manifest as sterically-constrained North (N) or South (S) conformations. Initially weak, off-target interactions of (N)-methanocarba adenosine derivatives were detected as leads that were structurally optimized to enhance activity and selectivity toward target proteins that normally do not recognize nucleosides. By this approach, novel modulators for 5HT2 serotonin and κ-opioid receptors, dopamine (DAT) and ATP-binding cassette (ABC) transporters were found, and previously undetected antiviral activities were revealed. Thus, through methanocarba nucleoside synthesis, structure-activity relationships, and multi-target pharmacology, a robust purinergic receptor scaffold has been repurposed to satisfy the pharmacophoric requirements of various GPCRs, enzymes and transporters.
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Affiliation(s)
- Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health Bethesda MD 20892-0810 USA +301 480 8422 +301 496 9024
| | - Veronica Salmaso
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health Bethesda MD 20892-0810 USA +301 480 8422 +301 496 9024
| | - R Rama Suresh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health Bethesda MD 20892-0810 USA +301 480 8422 +301 496 9024
| | - Dilip K Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health Bethesda MD 20892-0810 USA +301 480 8422 +301 496 9024
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Fu T, Li F, Zhang Y, Yin J, Qiu W, Li X, Liu X, Xin W, Wang C, Yu L, Gao J, Zheng Q, Zeng S, Zhu F. VARIDT 2.0: structural variability of drug transporter. Nucleic Acids Res 2021; 50:D1417-D1431. [PMID: 34747471 PMCID: PMC8728241 DOI: 10.1093/nar/gkab1013] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/08/2021] [Accepted: 11/04/2021] [Indexed: 12/20/2022] Open
Abstract
The structural variability data of drug transporter (DT) are key for research on precision medicine and rational drug use. However, these valuable data are not sufficiently covered by the available databases. In this study, a major update of VARIDT (a database previously constructed to provide DTs' variability data) was thus described. First, the experimentally resolved structures of all DTs reported in the original VARIDT were discovered from PubMed and Protein Data Bank. Second, the structural variability data of each DT were collected by literature review, which included: (a) mutation-induced spatial variations in folded state, (b) difference among DT structures of human and model organisms, (c) outward/inward-facing DT conformations and (d) xenobiotics-driven alterations in the 3D complexes. Third, for those DTs without experimentally resolved structural variabilities, homology modeling was further applied as well-established protocol to enrich such valuable data. As a result, 145 mutation-induced spatial variations of 42 DTs, 1622 inter-species structures originating from 292 DTs, 118 outward/inward-facing conformations belonging to 59 DTs, and 822 xenobiotics-regulated structures in complex with 57 DTs were updated to VARIDT (https://idrblab.org/varidt/ and http://varidt.idrblab.net/). All in all, the newly collected structural variabilities will be indispensable for explaining drug sensitivity/selectivity, bridging preclinical research with clinical trial, revealing the mechanism underlying drug-drug interaction, and so on.
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Affiliation(s)
- Tingting Fu
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.,Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Fengcheng Li
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yang Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang 050017, China
| | - Jiayi Yin
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wenqi Qiu
- Department of Surgery, HKU-SZH & Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Xuedong Li
- Department of Pharmacology, Hebei Medical University, Shijiazhuang 050017, China
| | - Xingang Liu
- Department of Pharmacology, Hebei Medical University, Shijiazhuang 050017, China
| | - Wenwen Xin
- Department of Pharmacology, Hebei Medical University, Shijiazhuang 050017, China
| | - Chengzhao Wang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang 050017, China
| | - Lushan Yu
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jianqing Gao
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.,Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China
| | - Qingchuan Zheng
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, China
| | - Su Zeng
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Feng Zhu
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.,Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou 330110, China
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Avram S, Stan MS, Udrea AM, Buiu C, Boboc AA, Mernea M. 3D-ALMOND-QSAR Models to Predict the Antidepressant Effect of Some Natural Compounds. Pharmaceutics 2021; 13:pharmaceutics13091449. [PMID: 34575524 PMCID: PMC8470101 DOI: 10.3390/pharmaceutics13091449] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/06/2021] [Accepted: 09/07/2021] [Indexed: 11/30/2022] Open
Abstract
The current treatment of depression involves antidepressant synthetic drugs that have a variety of side effects. In searching for alternatives, natural compounds could represent a solution, as many studies reported that such compounds modulate the nervous system and exhibit antidepressant effects. We used bioinformatics methods to predict the antidepressant effect of ten natural compounds with neuroleptic activity, reported in the literature. For all compounds we computed their drug-likeness, absorption, distribution, metabolism, excretion (ADME), and toxicity profiles. Their antidepressant and neuroleptic activities were predicted by 3D-ALMOND-QSAR models built by considering three important targets, namely serotonin transporter (SERT), 5-hydroxytryptamine receptor 1A (5-HT1A), and dopamine D2 receptor. For our QSAR models we have used the following molecular descriptors: hydrophobicity, electrostatic, and hydrogen bond donor/acceptor. Our results showed that all compounds present drug-likeness features as well as promising ADME features and no toxicity. Most compounds appear to modulate SERT, and fewer appear as ligands for 5-HT1A and D2 receptors. From our prediction, linalyl acetate appears as the only ligand for all three targets, neryl acetate appears as a ligand for SERT and D2 receptors, while 1,8-cineole appears as a ligand for 5-HT1A and D2 receptors.
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Affiliation(s)
- Speranta Avram
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, SplaiulIndependentei, No 91-95, 050095 Bucharest, Romania; (S.A.); (M.S.S.); (M.M.)
| | - Miruna Silvia Stan
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, SplaiulIndependentei, No 91-95, 050095 Bucharest, Romania; (S.A.); (M.S.S.); (M.M.)
- Research Institute of the University of Bucharest–ICUB, University of Bucharest, 91–95, SplaiulIndependentei, 050095 Bucharest, Romania;
| | - Ana Maria Udrea
- Research Institute of the University of Bucharest–ICUB, University of Bucharest, 91–95, SplaiulIndependentei, 050095 Bucharest, Romania;
- Laser Department, National Institute for Laser, Plasma and Radiation Physics, 077125 Magurele, Romania
| | - Cătălin Buiu
- Department of Automatic Control and Systems Engineering, Politehnica University of Bucharest, 313 SplaiulIndependenţei, 060042 Bucharest, Romania
- Correspondence: ; Tel.: +40-021-402-9167
| | - Anca Andreea Boboc
- “Maria Sklodowska Curie” Emergency Children’s Hospital, 20, Constantin Brancoveanu Bd., 077120 Bucharest, Romania;
- Department of Pediatrics 8, “Carol Davila” University of Medicine and Pharmacy, EroiiSanitari Bd., 020021 Bucharest, Romania
| | - Maria Mernea
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, SplaiulIndependentei, No 91-95, 050095 Bucharest, Romania; (S.A.); (M.S.S.); (M.M.)
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Islas ÁA, Moreno LG, Scior T. Induced fit, ensemble binding space docking and Monte Carlo simulations of MDMA 'ecstasy' and 3D pharmacophore design of MDMA derivatives on the human serotonin transporter (hSERT). Heliyon 2021; 7:e07784. [PMID: 34458620 PMCID: PMC8379675 DOI: 10.1016/j.heliyon.2021.e07784] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/26/2021] [Accepted: 08/11/2021] [Indexed: 10/24/2022] Open
Abstract
The popular recreational drug MDMA (3,4-methylenedioxy-methamphetamine) has a documented potential as a psychopharmacological clinical and research tool. This is due to its unique ability to promote reprocessing of traumatic memories, empathetic and pro-social states. Although it is established that MDMA exerts its behavioural effects via the serotonin transporter (SERT), the ligand-protein molecular interplay remains elusive. In order to shed light on the binding of MDMA and its primary congeneric entactogens (MDA, MBDB and MDAI), we first combined induced fit with Monte Carlo simulations. The computed interaction energies of the models correlated well with experimental activities (adjR2 = 0.78). Then we carried out 'ensemble binding space docking' on trajectories generated by interpolation of experimentally derived structures of the hSERT from the outward-open, and the occluded, to the inward-open states. This approach revealed low-energy alternative binding modes, suggesting high occupancy of the central site, yet considerable MDMA mobility within it, favouring the paroxetine-like orientation. Finally, we designed a pharmacophore that may be used to recognise hSERT-mediated serotonin releasers and uptake inhibitors of diverse chemical structure, identifying their active conformations and interacting residues. We conclude that the conserved amine-Asp98 ionic and edge-to-face π-π interactions are crucial to the mode of action of MDMA on the hSERT, underscoring the contributions of Tyr95 and gating residues Phe341, Tyr176 and Phe335. Amenable to experimental testing, our modelling may aid the rational design of novel entactogenic compounds and contribute to the understanding of an action mechanism, common and typical of psychotropic agents.
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Affiliation(s)
- Ángel A Islas
- Vicerrectoría de Investigación y Estudios de Posgrado, Benemérita Universidad Autónoma de Puebla, 4 Sur 303, Centro, 72000 Puebla, Pue., Mexico.,Facultad de Medicina, Universidad Autónoma de Puebla, Mexico
| | - Laura G Moreno
- Facultad de Medicina, Universidad Autónoma de Puebla, Mexico
| | - Thomas Scior
- Laboratory of Computational Molecular Simulations, Departamento de Farmacia, Benemérita Universidad Autónoma de Puebla, Mexico
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The antidepressant drug vilazodone is an allosteric inhibitor of the serotonin transporter. Nat Commun 2021; 12:5063. [PMID: 34417466 PMCID: PMC8379219 DOI: 10.1038/s41467-021-25363-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 08/05/2021] [Indexed: 12/12/2022] Open
Abstract
Depression is a common mental disorder. The standard medical treatment is the selective serotonin reuptake inhibitors (SSRIs). All characterized SSRIs are competitive inhibitors of the serotonin transporter (SERT). A non-competitive inhibitor may produce a more favorable therapeutic profile. Vilazodone is an antidepressant with limited information on its molecular interactions with SERT. Here we use molecular pharmacology and cryo-EM structural elucidation to characterize vilazodone binding to SERT. We find that it exhibits non-competitive inhibition of serotonin uptake and impedes dissociation of [3H]imipramine at low nanomolar concentrations. Our SERT structure with bound imipramine and vilazodone reveals a unique binding pocket for vilazodone, expanding the boundaries of the extracellular vestibule. Characterization of the binding site is substantiated with molecular dynamics simulations and systematic mutagenesis of interacting residues resulting in decreased vilazodone binding to the allosteric site. Our findings underline the versatility of SERT allosteric ligands and describe the unique binding characteristics of vilazodone. Vilazodone (VLZ) is a drug for the treatment of major depressive disorders that targets the serotonin transporter (SERT). Here, the authors combine pharmacology measurements and cryo-EM structural analysis to characterize VLZ binding to SERT and observe that VLZ exhibits non-competitive inhibition of serotonin transport and binds with nanomolar affinity to an allosteric site in SERT.
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Kowalska M, Fijałkowski Ł, Nowaczyk A. Assessment of Paroxetine Molecular Interactions with Selected Monoamine and γ-Aminobutyric Acid Transporters. Int J Mol Sci 2021; 22:6293. [PMID: 34208199 PMCID: PMC8230779 DOI: 10.3390/ijms22126293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/31/2021] [Accepted: 06/10/2021] [Indexed: 02/06/2023] Open
Abstract
Thus far, many hypotheses have been proposed explaining the cause of depression. Among the most popular of these are: monoamine, neurogenesis, neurobiology, inflammation and stress hypotheses. Many studies have proven that neurogenesis in the brains of adult mammals occurs throughout life. The generation of new neurons persists throughout adulthood in the mammalian brain due to the proliferation and differentiation of adult neural stem cells. For this reason, the search for drugs acting in this mechanism seems to be a priority for modern pharmacotherapy. Paroxetine is one of the most commonly used antidepressants. However, the exact mechanism of its action is not fully understood. The fact that the therapeutic effect after the administration of paroxetine occurs after a few weeks, even if the levels of monoamine are rapidly increased (within a few minutes), allows us to assume a neurogenic mechanism of action. Due to the confirmed dependence of depression on serotonin, norepinephrine, dopamine and γ-aminobutyric acid levels, studies have been undertaken into paroxetine interactions with these primary neurotransmitters using in silico and in vitro methods. We confirmed that paroxetine interacts most strongly with monoamine transporters and shows some interaction with γ-aminobutyric acid transporters. However, studies of the potency inhibitors and binding affinity values indicate that the neurogenic mechanism of paroxetine's action may be determined mainly by its interactions with serotonin transporters.
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Affiliation(s)
| | | | - Alicja Nowaczyk
- Department of Organic Chemistry, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 2 dr. A. Jurasza St., 85-094 Bydgoszcz, Poland; (M.K.); (Ł.F.)
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Extracellular loops of the serotonin transporter act as a selectivity filter for drug binding. J Biol Chem 2021; 297:100863. [PMID: 34118233 PMCID: PMC8253976 DOI: 10.1016/j.jbc.2021.100863] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 11/24/2022] Open
Abstract
The serotonin transporter (SERT) shapes serotonergic neurotransmission by retrieving its eponymous substrate from the synaptic cleft. Ligands that discriminate between SERT and its close relative, the dopamine transporter DAT, differ in their association rate constant rather than their dissociation rate. The structural basis for this phenomenon is not known. Here we examined the hypothesis that the extracellular loops 2 (EL2) and 4 (EL4) limit access to the ligand-binding site of SERT. We employed an antibody directed against EL4 (residues 388–400) and the antibody fragments 8B6 scFv (directed against EL2 and EL4) and 15B8 Fab (directed against EL2) and analyzed their effects on the transport cycle of and inhibitor binding to SERT. Electrophysiological recordings showed that the EL4 antibody and 8B6 scFv impeded the initial substrate-induced transition from the outward to the inward-facing conformation but not the forward cycling mode of SERT. In contrast, binding of radiolabeled inhibitors to SERT was enhanced by either EL4- or EL2-directed antibodies. We confirmed this observation by determining the association and dissociation rate of the DAT-selective inhibitor methylphenidate via electrophysiological recordings; occupancy of EL2 with 15B8 Fab enhanced the affinity of SERT for methylphenidate by accelerating its binding. Based on these observations, we conclude that (i) EL4 undergoes a major movement during the transition from the outward to the inward-facing state, and (ii) EL2 and EL4 limit access of inhibitors to the binding of SERT, thus acting as a selectivity filter. This insight has repercussions for drug development.
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Amphipathic environments for determining the structure of membrane proteins by single-particle electron cryo-microscopy. Q Rev Biophys 2021; 54:e6. [PMID: 33785082 DOI: 10.1017/s0033583521000044] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Over the past decade, the structural biology of membrane proteins (MPs) has taken a new turn thanks to epoch-making technical progress in single-particle electron cryo-microscopy (cryo-EM) as well as to improvements in sample preparation. The present analysis provides an overview of the extent and modes of usage of the various types of surfactants for cryo-EM studies. Digitonin, dodecylmaltoside, protein-based nanodiscs, lauryl maltoside-neopentyl glycol, glyco-diosgenin, and amphipols (APols) are the most popular surfactants at the vitrification step. Surfactant exchange is frequently used between MP purification and grid preparation, requiring extensive optimization each time the study of a new MP is undertaken. The variety of both the surfactants and experimental approaches used over the past few years bears witness to the need to continue developing innovative surfactants and optimizing conditions for sample preparation. The possibilities offered by novel APols for EM applications are discussed.
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Paroxetine-Overview of the Molecular Mechanisms of Action. Int J Mol Sci 2021; 22:ijms22041662. [PMID: 33562229 PMCID: PMC7914979 DOI: 10.3390/ijms22041662] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/31/2021] [Accepted: 02/04/2021] [Indexed: 12/20/2022] Open
Abstract
In the 21st century and especially during a pandemic, the diagnosis and treatment of depression is an essential part of the daily practice of many family doctors. It mainly affects patients in the age category 15–44 years, regardless of gender. Anxiety disorders are often diagnosed in children and adolescents. Social phobias can account for up to 13% of these diagnoses. Social anxiety manifests itself in fear of negative social assessment and humiliation, which disrupts the quality of social functioning. Treatment of the above-mentioned disorders is based on psychotherapy and pharmacotherapy. Serious side effects or mortality from antidepressant drug overdose are currently rare. Recent studies indicate that paroxetine (ATC code: N06AB), belonging to the selective serotonin reuptake inhibitors, has promising therapeutic effects and is used off-label in children and adolescents. The purpose of this review is to describe the interaction of paroxetine with several molecular targets in various points of view including the basic chemical and pharmaceutical properties. The central point of the review is focused on the pharmacodynamic analysis based on the molecular mechanism of binding paroxetine to various therapeutic targets.
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Hewett SJ, Prado VF, Robinson MB. The brain in flux: Genetic, physiologic, and therapeutic perspectives on transporters in the CNS. Neurochem Int 2021; 144:104980. [PMID: 33524471 DOI: 10.1016/j.neuint.2021.104980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Active and passive transporters constitute a gene family of approximately 2000 members. These proteins are required for import and export across the blood brain barrier, clearance of neurotransmitters, inter-cellular solute transfer, and transport across the membranes of subcellular organelles. Neurologic, neurodevelopmental, and psychiatric diseases have been linked to alterations in function and/or mutations in every one of these types of transporters, and many of the transporters are targeted by therapeutics. This is the 4th biennial special edition of Neurochemistry International that originates from a scientific meeting devoted to studies of transporters and their relationship to brain function and to neurodevelopmental, neurologic, and psychiatric disorders. This meeting provides the only international forum for the presentation and discussion of cutting-edge research on brain transporters covering fundamental aspects of transporter structure, function, and trafficking. Scientists describe the novel approaches being used to link this information to physiology/circuit function and behavior. The meeting also addresses translational topics surrounding mouse models of brain transporter disorders, novel human brain disorders arising from transporter mutations, and innovative therapeutic approaches centered on modification of transporter function. This special issue includes a sampling of review articles that address timely questions of the field and several primary research articles.
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Affiliation(s)
- Sandra J Hewett
- Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, NY, 13210, United States
| | - Vania F Prado
- Departments of Anatomy and Cell Biology, and Physiology and Pharmacology, Robarts Research Institute, University of Western Ontario London, ON, N6A5B7, Canada
| | - Michael B Robinson
- Departments of Pediatrics and Systems Pharmacology and Translational Therapeutics Children's Hospital of Philadelphia/University of Pennsylvania, Philadelphia, PA, 19104, United States.
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Li F, Egea PF, Vecchio AJ, Asial I, Gupta M, Paulino J, Bajaj R, Dickinson MS, Ferguson-Miller S, Monk BC, Stroud RM. Highlighting membrane protein structure and function: A celebration of the Protein Data Bank. J Biol Chem 2021; 296:100557. [PMID: 33744283 PMCID: PMC8102919 DOI: 10.1016/j.jbc.2021.100557] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 02/10/2021] [Accepted: 03/16/2021] [Indexed: 12/13/2022] Open
Abstract
Biological membranes define the boundaries of cells and compartmentalize the chemical and physical processes required for life. Many biological processes are carried out by proteins embedded in or associated with such membranes. Determination of membrane protein (MP) structures at atomic or near-atomic resolution plays a vital role in elucidating their structural and functional impact in biology. This endeavor has determined 1198 unique MP structures as of early 2021. The value of these structures is expanded greatly by deposition of their three-dimensional (3D) coordinates into the Protein Data Bank (PDB) after the first atomic MP structure was elucidated in 1985. Since then, free access to MP structures facilitates broader and deeper understanding of MPs, which provides crucial new insights into their biological functions. Here we highlight the structural and functional biology of representative MPs and landmarks in the evolution of new technologies, with insights into key developments influenced by the PDB in magnifying their impact.
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Affiliation(s)
- Fei Li
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA; Department of Neurology, University of California San Francisco, San Francisco, California, USA
| | - Pascal F Egea
- Department of Biological Chemistry, School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Alex J Vecchio
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | | | - Meghna Gupta
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA
| | - Joana Paulino
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA
| | - Ruchika Bajaj
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, California, USA
| | - Miles Sasha Dickinson
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA
| | - Shelagh Ferguson-Miller
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Brian C Monk
- Sir John Walsh Research Institute and Department of Oral Sciences, University of Otago, North Dunedin, Dunedin, New Zealand
| | - Robert M Stroud
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, USA.
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