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Sichler S, Höfner G, Nitsche V, Niessen KV, Seeger T, Worek F, Paintner FF, Wanner KT. Screening for new ligands of the MB327-PAM-1 binding site of the nicotinic acetylcholine receptor. Toxicol Lett 2024; 394:23-31. [PMID: 38387764 DOI: 10.1016/j.toxlet.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 01/08/2024] [Accepted: 02/18/2024] [Indexed: 02/24/2024]
Abstract
Intoxications with organophosphorus compounds (OPCs) effect a severe impairment of cholinergic neurotransmission that, as a result of overstimulation may lead to desensitization of nicotinic acetylcholine receptors (nAChRs) and finally to death due to respiratory paralysis. So far, therapeutics, that are capable to address and revert desensitized neuromuscular nAChRs into their resting, i.e. functional state are still missing. Still, among a class of compounds termed bispyridinium salts, which are characterized by the presence of two pyridinium subunits, constituents have been identified, that can counteract organophosphate poisoning by resensitizing desensitized nAChRs. According to comprehensive modeling studies this effect is mediated by an allosteric binding site at the nAChR termed MB327-PAM-1 site. For MB327, the most prominent representative of the bispyridinium salts and all other analogues studied so far, the affinity for the aforementioned binding site and the intrinsic activity measured in ex vivo and in in vivo experiments are distinctly too low, to meet the criteria to be fulfilled for therapeutic use. Hence, in order to identify new compounds with higher affinities for the MB327-PAM-1 binding site, as a basic requirement for an enhanced potency, two compound libraries, the ChemDiv library with 60 constituents and the Tocriscreen Plus library with 1280 members have been screened for hit compounds addressing the MB327-PAM-1 binding site, utilizing the [2H6]MB327 MS Binding Assay recently developed by us. This led to the identification of a set of 10 chemically diverse compounds, all of which exhibit an IC50 value of ≤ 10 µM (in the [2H6]MB327 MS Binding Assay), which had been defined as selection criteria. The three most affine ligands, which besides a quinazoline scaffold share similarities with regard to the substitution pattern and the nature of the substituents, are UNC0638, UNC0642 and UNC0646. With binding affinities expressed as pKi values of 6.01 ± 0.10, 5.97 ± 0.05 and 6.23 ± 0.02, respectively, these compounds exceed the binding affinity of MB327 by more than one log unit. This renders them promising starting points for the development of drugs for the treatment of organophosphorus poisoning by addressing the MB327-PAM-1 binding site of the nAChR.
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Affiliation(s)
- Sonja Sichler
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Georg Höfner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Valentin Nitsche
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Karin V Niessen
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Franz F Paintner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
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2
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Nitsche V, Höfner G, Kaiser J, Gertzen CGW, Seeger T, Niessen KV, Steinritz D, Worek F, Gohlke H, Paintner FF, Wanner KT. MS Binding Assays with UNC0642 as reporter ligand for the MB327 binding site of the nicotinic acetylcholine receptor. Toxicol Lett 2024; 392:94-106. [PMID: 38216073 DOI: 10.1016/j.toxlet.2024.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 12/28/2023] [Accepted: 01/06/2024] [Indexed: 01/14/2024]
Abstract
Intoxications with organophosphorus compounds (OPCs) based chemical warfare agents and insecticides may result in a detrimental overstimulation of muscarinic and nicotinic acetylcholine receptors evolving into a cholinergic crisis leading to death due to respiratory failure. In the case of the nicotinic acetylcholine receptor (nAChR), overstimulation leads to a desensitization of the receptor, which cannot be pharmacologically treated so far. Still, compounds interacting with the MB327 binding site of the nAChR like the bispyridinium salt MB327 have been found to re-establish the functional activity of the desensitized receptor. Only recently, a series of quinazoline derivatives with UNC0642 as one of the most prominent representatives has been identified to address the MB327 binding site of the nAChR, as well. In this study, UNC0642 has been utilized as a reporter ligand to establish new Binding Assays for this target. These assays follow the concept of MS Binding Assays for which by assessing the amount of bound reporter ligand by mass spectrometry no radiolabeled material is required. According to the results of the performed MS Binding Assays comprising saturation and competition experiments it can be concluded, that UNC0642 used as a reporter ligand addresses the MB327 binding site of the Torpedo-nAChR. This is further supported by the outcome of ex vivo studies carried out with poisoned rat diaphragm muscles as well as by in silico studies predicting the binding mode of UNC0646, an analog of UNC0642 with the highest binding affinity, in the recently proposed binding site of MB327 (MB327-PAM-1). With UNC0642 addressing the MB327 binding site of the Torpedo-nAChR, this and related quinazoline derivatives represent a promising starting point for the development of novel ligands of the nAChR as antidotes for the treatment of intoxications with organophosphorus compounds. Further, the new MS Binding Assays are a potent alternative to established assays and of particular value, as they do not require the use of radiolabeled material and are based on a commercially available compound as reporter ligand, UNC0642, exhibiting one of the highest binding affinities for the MB327 binding site known so far.
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Affiliation(s)
- Valentin Nitsche
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Georg Höfner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jesko Kaiser
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine Universität Düsseldorf, Düsseldorf, Germany
| | - Christoph G W Gertzen
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine Universität Düsseldorf, Düsseldorf, Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Karin V Niessen
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Dirk Steinritz
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine Universität Düsseldorf, Düsseldorf, Germany; Institute of Bio, and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich, Jülich, Germany
| | - Franz F Paintner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany.
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3
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Zaręba P, Łątka K, Mazur G, Gryzło B, Pasieka A, Godyń J, Panek D, Skrzypczak-Wiercioch A, Höfner GC, Latacz G, Maj M, Espargaró A, Sabaté R, Jóźwiak K, Wanner KT, Sałat K, Malawska B, Kulig K, Bajda M. Discovery of novel multifunctional ligands targeting GABA transporters, butyrylcholinesterase, β-secretase, and amyloid β aggregation as potential treatment of Alzheimer's disease. Eur J Med Chem 2023; 261:115832. [PMID: 37837674 DOI: 10.1016/j.ejmech.2023.115832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/12/2023] [Accepted: 09/23/2023] [Indexed: 10/16/2023]
Abstract
Alzheimer's disease (AD) is a global health problem in the medical sector that will increase over time. The limited treatment of AD leads to the search for a new clinical candidate. Considering the multifactorial nature of AD, a strategy targeting number of regulatory proteins involved in the development of the disease is an effective approach. Here, we present a discovery of new multi-target-directed ligands (MTDLs), purposely designed as GABA transporter (GAT) inhibitors, that successfully provide the inhibitory activity against butyrylcholinesterase (BuChE), β-secretase (BACE1), amyloid β aggregation and calcium channel blockade activity. The selected GAT inhibitors, 19c and 22a - N-benzylamide derivatives of 4-aminobutyric acid, displayed the most prominent multifunctional profile. Compound 19c (mGAT1 IC50 = 10 μM, mGAT4 IC50 = 12 μM and BuChE IC50 = 559 nM) possessed the highest hBACE1 and Aβ40 aggregation inhibitory activity (IC50 = 1.57 μM and 99 % at 10 μM, respectively). Additionally, it showed a decrease in both the elongation and nucleation constants of the amyloid aggregation process. In contrast compound 22a represented the highest activity and a mixed-type of eqBuChE inhibition (IC50 = 173 nM) with hBACE1 (IC50 = 9.42 μM), Aβ aggregation (79 % at 10 μM) and mGATs (mGAT1 IC50 = 30 μM, mGAT4 IC50 = 25 μM) inhibitory activity. Performed molecular docking studies described the mode of interactions with GATs and enzymatic targets. In ADMET in vitro studies both compounds showed acceptable metabolic stability and low neurotoxicity. Successfully, compounds 19c and 22a at the dose of 30 mg/kg possessed statistically significant antiamnesic properties in a mouse model of amnesia caused by scopolamine and assessed in the novel object recognition (NOR) task or the passive avoidance (PA) task.
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Affiliation(s)
- Paula Zaręba
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Kamil Łątka
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Gabriela Mazur
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Beata Gryzło
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Anna Pasieka
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Justyna Godyń
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Dawid Panek
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Anna Skrzypczak-Wiercioch
- Department of Animal Anatomy and Preclinical Sciences, University Centre of Veterinary Medicine JU-UA, University of Agriculture in Kraków, Mickiewicz 24/28 St., 30-059, Kraków, Poland
| | - Georg C Höfner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München Butenandtstr., 5-13, 81377, Munich, Germany
| | - Gniewomir Latacz
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Maciej Maj
- Department of Biopharmacy, Medical University of Lublin, W. Chodzki 4a St., 20-093, Lublin, Poland
| | - Alba Espargaró
- Department of Pharmacy and Pharmaceutical Technology and Physical-Chemistry, School of Pharmacy and Food Sciences, University of Barcelona, Av Joan XXIII 27-31, 08028, Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), Av Joan XXIII, S/N, 08028, Barcelona, Spain
| | - Raimon Sabaté
- Department of Pharmacy and Pharmaceutical Technology and Physical-Chemistry, School of Pharmacy and Food Sciences, University of Barcelona, Av Joan XXIII 27-31, 08028, Barcelona, Spain; Institute of Nanoscience and Nanotechnology (IN2UB), Av Joan XXIII, S/N, 08028, Barcelona, Spain
| | - Krzysztof Jóźwiak
- Department of Biopharmacy, Medical University of Lublin, W. Chodzki 4a St., 20-093, Lublin, Poland
| | - Klaus T Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München Butenandtstr., 5-13, 81377, Munich, Germany
| | - Kinga Sałat
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Barbara Malawska
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Katarzyna Kulig
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland
| | - Marek Bajda
- Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 St., 30-688, Kraków, Poland.
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Nayak SR, Joseph D, Höfner G, Dakua A, Athreya A, Wanner KT, Kanner BI, Penmatsa A. Cryo-EM structure of GABA transporter 1 reveals substrate recognition and transport mechanism. Nat Struct Mol Biol 2023; 30:1023-1032. [PMID: 37400654 PMCID: PMC10352132 DOI: 10.1038/s41594-023-01011-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 05/04/2023] [Indexed: 07/05/2023]
Abstract
The inhibitory neurotransmitter γ-aminobutyric acid (GABA) is cleared from the synaptic cleft by the sodium- and chloride-coupled GABA transporter GAT1. Inhibition of GAT1 prolongs the GABAergic signaling at the synapse and is a strategy to treat certain forms of epilepsy. In this study, we present the cryo-electron microscopy structure of Rattus norvegicus GABA transporter 1 (rGAT1) at a resolution of 3.1 Å. The structure elucidation was facilitated by epitope transfer of a fragment-antigen binding (Fab) interaction site from the Drosophila dopamine transporter (dDAT) to rGAT1. The structure reveals rGAT1 in a cytosol-facing conformation, with a linear density in the primary binding site that accommodates a molecule of GABA, a displaced ion density proximal to Na site 1 and a bound chloride ion. A unique insertion in TM10 aids the formation of a compact, closed extracellular gate. Besides yielding mechanistic insights into ion and substrate recognition, our study will enable the rational design of specific antiepileptics.
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Affiliation(s)
| | - Deepthi Joseph
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
- Department of Molecular Biosciences, College of Natural Sciences, University of Texas at Austin, Austin, TX, USA
| | - Georg Höfner
- Department of Pharmacy, Center for Drug Research, Ludwig Maximilians University of Munich, Munich, Germany
| | - Archishman Dakua
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
- Biophysics Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Arunabh Athreya
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Klaus T Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig Maximilians University of Munich, Munich, Germany
| | - Baruch I Kanner
- Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada, Hebrew University, Hadassah Medical School, Jerusalem, Israel
| | - Aravind Penmatsa
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.
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Währa M, Allmendinger L, Höfner G, Wanner KT. Benocyclidine (BTCP) as Non-labelled Reporter Ligand for MS Binding Assays for the PCP Ion Channel Binding Site of the Desensitized Torpedo Nicotinic Acetylcholine Receptor (nAChR). ChemMedChem 2023; 18:e202300048. [PMID: 36840942 DOI: 10.1002/cmdc.202300048] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 02/20/2023] [Accepted: 02/23/2023] [Indexed: 02/26/2023]
Abstract
In this study we present MS Binding Assays for the PCP ion channel binding site of Torpedo californica nicotinic acetylcholine receptor (nAChR) as an alternative to radioligand binding assays. As MS Marker Benocyclidine (BTCP) was employed, found to be more affine (Kd of 84.2 nM) than the radioligands, e. g. [3 H]PCP, used so far in respective binding assays. Based on a highly sensitive and fast LC-ESI-MS/MS method for quantification of BTCP samples, BTCP MS Binding Assays for the PCP ion channel binding site of Torpedo nAChR could be established comprising saturation, kinetic and competition experiments. The affinities obtained in competitive BTCP MS Binding Assays for ligands addressing the PCP ion channel binding site of Torpedo nAChR were in excellent accord with those reported from radioligand experiments. Thus, the new BTCP MS Binding Assays represent a potent and reliable alternative to radioligand binding assays used so far for the characterization of ligand binding to the PCP ion channel binding site of the nAChR.
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Affiliation(s)
- Mark Währa
- Ludwig-Maximilians-Universität München, Butenandtstraße 7, 81377, Munich, Germany
| | - Lars Allmendinger
- Ludwig-Maximilians-Universität München, Butenandtstraße 7, 81377, Munich, Germany
| | - Georg Höfner
- Ludwig-Maximilians-Universität München, Butenandtstraße 7, 81377, Munich, Germany
| | - Klaus T Wanner
- Ludwig-Maximilians-Universität München, Butenandtstraße 7, 81377, Munich, Germany
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Kaiser J, Gertzen CG, Bernauer T, Höfner G, Niessen KV, Seeger T, Paintner FF, Wanner KT, Worek F, Thiermann H, Gohlke H. A novel binding site in the nicotinic acetylcholine receptor for MB327 can explain its allosteric modulation relevant for organophosphorus-poisoning treatment. Toxicol Lett 2022; 373:160-171. [DOI: 10.1016/j.toxlet.2022.11.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/25/2022] [Indexed: 11/27/2022]
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Kipka H, Tomasi R, Hübner M, Liebchen U, Hagl C, Wanner KT, Mannell H, Höfner G. Simultaneous LC-ESI-MS/MS Quantification of Levosimendan and Its Metabolites for Therapeutic Drug Monitoring of Cardiac Surgery Patients. Pharmaceutics 2022; 14:pharmaceutics14071454. [PMID: 35890349 PMCID: PMC9319272 DOI: 10.3390/pharmaceutics14071454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 02/04/2023] Open
Abstract
Levosimendan is used in severe chronic cardiac insufficiency, also within the peri-operative setting. Real-life pharmacokinetic data in surgical patients is lacking, making therapeutic drug monitoring (TDM) of levosimendan, its pharmacologically active metabolite OR-1896, and its intermediate OR-1855 important. A simultaneous highly sensitive quantification of levosimendan and its metabolites in small-volume samples has not yet been described. Here, levosimendan (LLOQ 0.450 nM), OR-1896, and OR-1855 (LLOQ both 1.0 nM) were successfully quantified by LC-ESI-MS/MS after liquid-liquid extraction in 300 µL of blood. A short C8 column under reversed-phase conditions enabled simultaneous and fast quantification of levosimendan in the negative and the metabolites in the positive ionization mode in a single run within 2 min. Interestingly and unexpectedly, constitutional isomers of levosimendan metabolites with identical mass transitions and similar retention times were observed in surgical patients’ samples, which we identified as the metamizole metabolites 4-aminoantipyrine and 4-acetamidoantipyrine. A longer C8 column and a modified mobile phase enabled selective quantification of all analytes in a single run within 7 min. We developed, validated, and applied highly sensitive LC-ESI-MS/MS methods for simultaneous quantification of levosimendan and its metabolites, enabling efficient TDM of cardiac surgery patients even with additional metamizole administration.
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Affiliation(s)
- Hannah Kipka
- Doctoral Program Clinical Pharmacy, University Hospital, LMU Munich, 81377 Munich, Germany;
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, 82152 Planegg, Germany
- Correspondence:
| | - Roland Tomasi
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany; (R.T.); (M.H.); (U.L.)
| | - Max Hübner
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany; (R.T.); (M.H.); (U.L.)
- Walter Brendel Center of Experimental Medicine, LMU Munich, 81377 Munich, Germany
| | - Uwe Liebchen
- Department of Anaesthesiology, University Hospital, LMU Munich, 81377 Munich, Germany; (R.T.); (M.H.); (U.L.)
| | - Christian Hagl
- Department of Cardiac Surgery, University Hospital, LMU Munich, 81377 Munich, Germany;
- DZHK (German Centre of Cardiovascular Research), Partner Site Munich Heart Alliance, 81377 Munich, Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, 81377 Munich, Germany; (K.T.W.); (G.H.)
| | - Hanna Mannell
- Doctoral Program Clinical Pharmacy, University Hospital, LMU Munich, 81377 Munich, Germany;
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, 82152 Planegg, Germany
| | - Georg Höfner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, 81377 Munich, Germany; (K.T.W.); (G.H.)
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Ackermann TM, Höfner G, Wanner KT. Screening for New Inhibitors of Glycine Transporter 1 and 2 by Means of MS Binding Assays. ChemMedChem 2021; 16:3094-3104. [PMID: 34174033 PMCID: PMC8518836 DOI: 10.1002/cmdc.202100408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Indexed: 11/10/2022]
Abstract
A straightforward screening of a compound library comprising 2439 substances for the identification of new inhibitors for the neurotransmitter transporters GlyT1 and GlyT2 is described. Screening and full-scale competition experiments were performed using recently developed GlyT1 and GlyT2 MS Binding Assays. That way for both targets, GlyT1 and GlyT2, ligands were identified, which exhibited affinities (pKi values) in the low micromolar to sub-micromolar range. The majority of these binders exhibit new chemical scaffolds in the class of GlyT1 and GlyT2 inhibitors, which could be of interest for the development of new ligands with improved affinities for the target proteins. Additionally, compounds with excellent fluorescent properties were found for GlyT2, which renders them promising compounds for future fluorescence-based techniques. All in all, this study demonstrates that MS Binding Assays represent a powerful technology platform also well suited for the screening of compound libraries in a highly reliable and effective manner.
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Affiliation(s)
- Thomas M. Ackermann
- Department of Pharmacy – Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
| | - Georg Höfner
- Department of Pharmacy – Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
| | - Klaus T. Wanner
- Department of Pharmacy – Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
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Gryzło B, Zaręba P, Malawska K, Mazur G, Rapacz A, Ła̧tka K, Höfner GC, Latacz G, Bajda M, Sałat K, Wanner KT, Malawska B, Kulig K. Novel Functionalized Amino Acids as Inhibitors of GABA Transporters with Analgesic Activity. ACS Chem Neurosci 2021; 12:3073-3100. [PMID: 34347423 PMCID: PMC8397297 DOI: 10.1021/acschemneuro.1c00351] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
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Neuropathic pain
resistance to pharmacotherapy has encouraged researchers
to develop effective therapies for its treatment. γ-Aminobutyric
acid (GABA) transporters 1 and 4 (mGAT1 and mGAT4) have been increasingly
recognized as promising drug targets for neuropathic pain (NP) associated
with imbalances in inhibitory neurotransmission. In this context,
we designed and synthesized new functionalized amino acids as inhibitors
of GABA uptake and assessed their activities toward all four mouse
GAT subtypes (mGAT1–4). According to the obtained results,
compounds 2RS,4RS-39c (pIC50 (mGAT4) = 5.36), 50a (pIC50 (mGAT2) = 5.43), and 56a (with moderate subtype selectivity
that favored mGAT4, pIC50 (mGAT4) = 5.04) were of particular
interest and were therefore evaluated for their cytotoxic and hepatotoxic
effects. In a set of in vivo experiments, both compounds 50a and 56a showed antinociceptive properties
in three rodent models of NP, namely, chemotherapy-induced neuropathic
pain models (the oxaliplatin model and the paclitaxel model) and the
diabetic neuropathic pain model induced by streptozotocin; however
compound 56a demonstrated predominant activity. Since
impaired motor coordination is also observed in neuropathic pain conditions,
we have pointed out that none of the test compounds induced motor
deficits in the rotarod test.
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Affiliation(s)
- Beata Gryzło
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Paula Zaręba
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Katarzyna Malawska
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Gabriela Mazur
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Anna Rapacz
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Kamil Ła̧tka
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Georg C. Höfner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München Butenandtstraße 5-13, 81377 Munich, Germany
| | - Gniewomir Latacz
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Marek Bajda
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Kinga Sałat
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Klaus T. Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München Butenandtstraße 5-13, 81377 Munich, Germany
| | - Barbara Malawska
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
| | - Katarzyna Kulig
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
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10
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Zaręba P, Sałat K, Höfner GC, Łątka K, Bajda M, Latacz G, Kotniewicz K, Rapacz A, Podkowa A, Maj M, Jóźwiak K, Filipek B, Wanner KT, Malawska B, Kulig K. Development of tricyclic N-benzyl-4-hydroxybutanamide derivatives as inhibitors of GABA transporters mGAT1-4 with anticonvulsant, antinociceptive, and antidepressant activity. Eur J Med Chem 2021; 221:113512. [PMID: 34015586 DOI: 10.1016/j.ejmech.2021.113512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 01/04/2023]
Abstract
γ-Aminobutyric acid (GABA) neurotransmission has a significant impact on the proper functioning of the central nervous system. Numerous studies have indicated that inhibitors of the GABA transporters mGAT1-4 offer a promising strategy for the treatment of several neurological disorders, including epilepsy, neuropathic pain, and depression. Following our previous results, herein, we report the synthesis, biological evaluation, and structure-activity relationship studies supported by molecular docking and molecular dynamics of a new series of N-benzyl-4-hydroxybutanamide derivatives regarding their inhibitory potency toward mGAT1-4. This study allowed us to identify compound 23a (N-benzyl-4-hydroxybutanamide bearing a dibenzocycloheptatriene moiety), a nonselective GAT inhibitor with a slight preference toward mGAT4 (pIC50 = 5.02 ± 0.11), and compound 24e (4-hydroxy-N-[(4-methylphenyl)-methyl]butanamide bearing a dibenzocycloheptadiene moiety) with relatively high inhibitory activity toward mGAT2 (pIC50 = 5.34 ± 0.09). In a set of in vivo experiments, compound 24e successively showed predominant anticonvulsant activity and antinociception in the formalin model of tonic pain. In contrast, compound 23a showed significant antidepressant-like properties in mice. These results were consistent with the available literature data, which indicates that, apart from seizure control, GABAergic neurotransmission is also involved in the pathophysiology of several psychiatric diseases, however alternative mechanisms underlying this action cannot be excluded. Finally, it is worth noting that the selected compounds showed unimpaired locomotor skills that have been indicated to give reliable results in behavioral assays.
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Affiliation(s)
- Paula Zaręba
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland.
| | - Kinga Sałat
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Georg C Höfner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München Butenandtstr, 5-13, 81377, Munich, Germany
| | - Kamil Łątka
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Marek Bajda
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Gniewomir Latacz
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Krzysztof Kotniewicz
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Anna Rapacz
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Adrian Podkowa
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Maciej Maj
- Department of Biopharmacy, Medical University of Lublin, ul. W. Chodzki 4a, 20-093, Lublin, Poland
| | - Krzysztof Jóźwiak
- Department of Biopharmacy, Medical University of Lublin, ul. W. Chodzki 4a, 20-093, Lublin, Poland
| | - Barbara Filipek
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Klaus T Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München Butenandtstr, 5-13, 81377, Munich, Germany
| | - Barbara Malawska
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
| | - Katarzyna Kulig
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna St, 30-688, Kraków, Poland
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11
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Andreß JC, Höfner G, Wanner KT. Withdrawal: K.T. Wanner et al. "MS-based screening of small amino acid derived oxime libraries for hGAT3 inhibitors". ChemMedChem 2021; 16:724. [PMID: 33135362 DOI: 10.1002/cmdc.202000720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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12
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Ackermann TM, Allmendinger L, Höfner G, Wanner KT. MS Binding Assays for Glycine Transporter 2 (GlyT2) Employing Org25543 as Reporter Ligand. ChemMedChem 2021; 16:199-215. [PMID: 32734692 PMCID: PMC7821181 DOI: 10.1002/cmdc.202000342] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/29/2020] [Indexed: 12/13/2022]
Abstract
This study describes the first binding assay for glycine transporter 2 (GlyT2) following the concept of MS Binding Assays. The selective GlyT2 inhibitor Org25543 was employed as a reporter ligand and it was quantified with a highly sensitive and rapid LC-ESI-MS/MS method. Binding of Org25543 at GlyT2 was characterized in kinetic and saturation experiments with an off-rate of 7.07×10-3 s-1 , an on-rate of 1.01×106 M-1 s-1 , and an equilibrium dissociation constant of 7.45 nM. Furthermore, the inhibitory constants of 19 GlyT ligands were determined in competition experiments. The validity of the GlyT2 affinities determined with the binding assay was examined by a comparison with published inhibitory potencies from various functional assays. With the capability for affinity determination towards GlyT2 the developed MS Binding Assays provide the first tool for affinity profiling of potential ligands and it represents a valuable new alternative to functional assays addressing GlyT2.
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Affiliation(s)
- Thomas M. Ackermann
- Department of Pharmacy, Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
| | - Lars Allmendinger
- Department of Pharmacy, Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
| | - Georg Höfner
- Department of Pharmacy, Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
| | - Klaus T. Wanner
- Department of Pharmacy, Center for Drug ResearchLudwig-Maximilians-Universität MunichButenandtstraße 781377MunichGermany
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13
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Gabriel J, Höfner G, Wanner KT. Combination of MS Binding Assays and affinity selection mass spectrometry for screening of structurally homogenous libraries as exemplified for a focused oxime library addressing the neuronal GABA transporter 1. Eur J Med Chem 2020; 206:112598. [PMID: 32896797 DOI: 10.1016/j.ejmech.2020.112598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 11/30/2022]
Abstract
This study presents an efficient screening approach based on combination of mass spectrometry (MS) based binding assays (MS Binding Assays) and affinity selection mass spectrometry (ASMS) customized for screening of structurally homogeneous libraries sharing a common mass spectrometric fragmentation pattern. After reaction of a nipecotic acid derivative possessing a hydroxylamine functionality with aldehydes, the resulting oxime library was screened accordingly toward the GABA transporter subtype 1 (GAT1), a drug target for several neurological disorders. After assessing sublibraries' activities for inhibition of reporter ligand binding, hits in active ones were directly identified. This could be achieved by recording mass transitions for the reporter ligand as well as those predicted for the library components in a single LC-MS/MS run with a triple quadrupole mass spectrometer in the multiple reaction monitoring mode. Identification of hits with a predefined affinity could be reliably accomplished by calculation of IC50-values from specific binding concentrations of library constituents and reporter ligand. Application of this strategy revealed six hits, from which two of them were resynthesized for further biological evaluation. Thereby, the best one displayed a pKi of 7.38 in MS Binding Assays and a pIC50 of 6.82 in [3H]GABA uptake assays for GAT1.
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Affiliation(s)
- Jürgen Gabriel
- Faculty of Chemistry and Pharmacy, Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Georg Höfner
- Faculty of Chemistry and Pharmacy, Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Klaus T Wanner
- Faculty of Chemistry and Pharmacy, Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany.
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14
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Rudy HA, Mayer P, Wanner KT. Synthesis of 1,5‐Ring‐Fused Imidazoles from Cyclic Imines and TosMIC – Identification of in situ Generated
N
‐Methyleneformamide as a Catalyst in the van Leusen Imidazole Synthesis. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Heinrich‐Karl A. Rudy
- Department für Pharmazie Zentrum für Pharmaforschung Ludwig‐Maximilians‐Universität München Butenandtstr. 5‐13. 81377 München Germany
| | - Peter Mayer
- Department für Chemie Ludwig‐Maximilians‐Universität München Butenandtstr. 5‐13. 81377 München Germany
| | - Klaus T. Wanner
- Department für Pharmazie Zentrum für Pharmaforschung Ludwig‐Maximilians‐Universität München Butenandtstr. 5‐13. 81377 München Germany
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15
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Andreß JC, Böck MC, Höfner G, Wanner KT. Synthesis and biological evaluation of α- and β-hydroxy substituted amino acid derivatives as potential mGAT1–4 inhibitors. Med Chem Res 2020. [DOI: 10.1007/s00044-020-02548-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AbstractIn this study, we report the synthesis and biological evaluation of a variety of α- and β-hydroxy substituted amino acid derivatives as potential amino acid subunits in inhibitors of GABA uptake transporters (GATs). In order to ensure that the test compounds adopt a binding pose similar to that presumed for related larger GAT inhibitors, lipophilic residues were introduced either at the amino nitrogen atom or at the alcohol function. Several of the synthesized compounds were found to exhibit similar inhibitory activity at the GAT subtypes mGAT2, mGAT3, and mGAT4, respectively, as compared with the reference N-butylnipecotic acid. Hence, these compounds might serve as starting point for future developments of more complex GAT inhibitors.
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16
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Abstract
Potential mGAT4 inhibitors derived from the lead substance (S)-SNAP-5114 have been synthesized and characterized for their inhibitory potency. Variations from the parent compound included the substitution of one of its aromatic 4-methoxy and 4-methoxyphenyl groups, respectively, with a more polar moiety, including a carboxylic acid, alcohol, nitrile, carboxamide, sulfonamide, aldehyde or ketone function, or amino acid partial structures. Furthermore, it was investigated how the substitution of more than one of the aromatic 4-methoxy groups affects the potency and selectivity of the resulting compounds. Among the synthesized test substances (S)-1-{2-[(4-formylphenyl)bis(4-methoxyphenyl)-methoxy]ethyl}piperidine-3-carboxylic acid, that features a carbaldehyde function in place of one of the aromatic 4-methoxy moieties of (S)-SNAP-5114, was found to have a pIC50 value of 5.89±0.07, hence constituting a slightly more potent mGAT4 inhibitor than the parent substance while showing comparable subtype selectivity.
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Affiliation(s)
- Michael C. Böck
- Department of Pharmacy – Center for Drug ResearchLudwig-Maximilians-Universität MünchenButenandtstraße 5–1381377MunichGermany
| | - Georg Höfner
- Department of Pharmacy – Center for Drug ResearchLudwig-Maximilians-Universität MünchenButenandtstraße 5–1381377MunichGermany
| | - Klaus T. Wanner
- Department of Pharmacy – Center for Drug ResearchLudwig-Maximilians-Universität MünchenButenandtstraße 5–1381377MunichGermany
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17
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Zaręba P, Gryzło B, Malawska K, Sałat K, Höfner GC, Nowaczyk A, Fijałkowski Ł, Rapacz A, Podkowa A, Furgała A, Żmudzki P, Wanner KT, Malawska B, Kulig K. Novel mouse GABA uptake inhibitors with enhanced inhibitory activity toward mGAT3/4 and their effect on pain threshold in mice. Eur J Med Chem 2020; 188:111920. [DOI: 10.1016/j.ejmech.2019.111920] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 11/16/2019] [Accepted: 11/27/2019] [Indexed: 12/12/2022]
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18
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Rudy HKA, Wanner KT. Accessing Tricyclic Imines Comprising a 2-Azabicyclo[2.2.2]octane Scaffold by Intramolecular Hetero-Diels–Alder Reaction of 4-Alkenyl-Substituted N-Silyl-1,4-dihydropyridines. SYNTHESIS-STUTTGART 2019. [DOI: 10.1055/s-0039-1690619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Tricyclic imines inheriting a 2-azabicyclo[2.2.2]octane (isoquinuclidine) scaffold were provided with high regioselectivity in moderate to very good yields by a smooth, broadly applicable intramolecular hetero-Diels–Alder reaction of various 4-ω-alkenyl-substituted 1,4-dihydropyridines (DHPs) under trifluoroacetic acid catalysis. The required 4,4-disubstituted 1,4-DHPs were obtained by introduction of ω-alkenyl moieties of varying chain length via diorganomagnesium reagents into the 4-position of diversely 4-substituted pyridines after prior N-activation with triisopropylsilyltriflate.
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Affiliation(s)
| | - Klaus T. Wanner
- Ludwig-Maximilians-Universität München, Department für Pharmazie – Zentrum für Pharmaforschung
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19
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Gabriel J, Höfner G, Wanner KT. A Library Screening Strategy Combining the Concepts of MS Binding Assays and Affinity Selection Mass Spectrometry. Front Chem 2019; 7:665. [PMID: 31637233 PMCID: PMC6787468 DOI: 10.3389/fchem.2019.00665] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 09/18/2019] [Indexed: 01/16/2023] Open
Abstract
The primary objective of early drug development is to identify hits and leads for a target of interest. To achieve this aim, rapid, and reliable screening techniques for a huge number of compounds are needed. Mass spectrometry based binding assays (MS Binding Assays) represent a well-established technique for library screening based on competitive binding experiments revealing active sublibraries due to reduced binding of a reporter ligand and following hit identification for active libraries by deconvolution in further competitive binding experiments. In the present study, we combined the concepts of MS Binding Assays and affinity selection mass spectrometry (ASMS) to improve the efficiency of the hit identification step. In that case, only a single competitive binding experiment is performed that is in the first step analyzed for reduced binding of the reporter ligand and—only if a sublibrary is active—additionally for specific binding of individual library components. Subsequently, affinities of identified hits as well as activities of reduced sublibraries (i.e., all sublibrary components without hit) are assessed in additional competitive binding experiments. We exemplified this screening concept for the identification of ligands addressing the most widespread GABA transporter subtype in the brain (GAT1) studying in the beginning a library composed of 128 and further on a library of 1,280 well-characterized GAT1 inhibitors, drug substances, and pharmacological tool compounds. Determination of sublibraries' activities was done by quantification of bound NO711 as reporter ligand and hit identification for the active ones achieved in a further LC-ESI-MS/MS run in the multiple reaction monitoring mode enabling detection of all sublibrary components followed by hit verification and investigation of reduced sublibraries in further competitive binding experiments. In this way, we could demonstrate that all GAT1 inhibitors reducing reporter ligand binding below 50% at a concentration of 1 μM are detected reliably without generation of false positive or false negative hits. As the described strategy is apart from its reliability also highly efficient, it can be assumed to become a valuable tool in early drug research, especially for membrane integrated drug targets that are often posing problems in established screening techniques.
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Affiliation(s)
- Jürgen Gabriel
- Department of Pharmacy, Faculty of Chemistry and Pharmacy, Ludwig Maximilian University München, Munich, Germany
| | - Georg Höfner
- Department of Pharmacy, Faculty of Chemistry and Pharmacy, Ludwig Maximilian University München, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy, Faculty of Chemistry and Pharmacy, Ludwig Maximilian University München, Munich, Germany
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20
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Schaarschmidt M, Höfner G, Wanner KT. Front Cover: Synthesis and Biological Evaluation of Nipecotic Acid and Guvacine Derived 1,3‐Disubstituted Allenes as Inhibitors of Murine GABA Transporter mGAT1 (ChemMedChem 12/2019). ChemMedChem 2019. [DOI: 10.1002/cmdc.201900336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Maren Schaarschmidt
- Department of Pharmacy—Center for Drug ResearchLudwig-Maximilians-Universität München Butenandtstr. 7–13 81377 Munich Germany
| | - Georg Höfner
- Department of Pharmacy—Center for Drug ResearchLudwig-Maximilians-Universität München Butenandtstr. 7–13 81377 Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy—Center for Drug ResearchLudwig-Maximilians-Universität München Butenandtstr. 7–13 81377 Munich Germany
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21
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Schaarschmidt M, Höfner G, Wanner KT. Synthesis and Biological Evaluation of Nipecotic Acid and Guvacine Derived 1,3-Disubstituted Allenes as Inhibitors of Murine GABA Transporter mGAT1. ChemMedChem 2019; 14:1135-1151. [PMID: 30957949 DOI: 10.1002/cmdc.201900170] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Indexed: 12/18/2022]
Abstract
A new class of nipecotic acid and guvacine derivatives has been synthesized and characterized for their inhibitory potency at mGAT1-4 and binding affinity for mGAT1. Compounds of the described class are defined by a four-carbon-atom allenyl spacer connecting the nitrogen atom of the nipecotic acid or guvacine head with an aromatic residue. Among the compounds investigated, the mixture of nipecotic acid derivatives rac-{(Ra )-1-[4-([1,1':2',1''-terphenyl]-2-yl)buta-2,3-dien-1-yl](3R)-piperidine-3-carboxylic acid} and rac-{(Sa )-1-[4-([1,1':2',1''-terphenyl]-2-yl)buta-2,3-dien-1-yl](3R)-piperidine-3-carboxylic acid} (21 p), possessing an o-terphenyl residue, was identified as highly selective and the most potent mGAT1 inhibitor in this study. For the (R)-nipecotic acid derived form of 21 p, the inhibitory potency in [3 H]GABA uptake assays was determined as pIC50 =6.78±0.08, and the binding affinity in MS Binding Assays as pKi =7.10±0.12. The synthesis of the designed compounds was carried out by a two-step procedure, generating the allene moiety via allenylation of terminal alkynes which allows broad variation of the terminal phenyl and biphenyl subunit.
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Affiliation(s)
- Maren Schaarschmidt
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 7-13, 81377, Munich, Germany
| | - Georg Höfner
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 7-13, 81377, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 7-13, 81377, Munich, Germany
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22
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Petz S, Allmendinger L, Mayer P, Wanner KT. Construction of 4-substituted 2-(pyrrolidine-3-yl)acetic acid derivatives as cyclic γ-aminobutyric acid analogues employing intermolecular [2+2]-photocycloaddition as key steps. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.03.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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23
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Wein T, Wanner KT, Rappenglück S, Sichler S, Niessen KV, Seeger T, Worek F, Thiermann H. New Resensitizers for the Nicotinic Acetylcholine Receptor by Ligand-Based Pharmacophore Modeling. Curr Comput Aided Drug Des 2019; 15:104-109. [PMID: 29968541 DOI: 10.2174/1573409914666180703120201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 06/12/2018] [Accepted: 06/21/2018] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Irreversible inhibition of the acetylcholinesterase upon intoxication with organophosphorus compounds leads to an accumulation of acetylcholine in the synaptic cleft and a subsequent desensitization of nicotinic acetylcholine receptors which may ultimately result in respiratory failure. A direct intervention at the nicotinic acetylcholine receptor (nAChR) was proposed as an alternative therapeutic approach to the treatment with atropine and oximes. METHODS The bispyridinium compound MB327 has been found to recover functional activity of nAChR thus representing a promising starting point for the development of new drugs for the treatment of organophosphate poisoning. Recent solid-supported membrane-based electrophysiological experiments have identified symmetrically substituted bispyridinium compounds e.g. MB327, MB583, and PTM0001 that are able to resensitize nAChR of Torpedo californica. In addition, six compounds have been found not to show any resensitizing potential and were thus classified as inactive. This set of active and inactive bispyridinium compounds was taken to develop a pharmacophore model and in silico screening of a virtual database of bispyridinium compounds to identify new compounds that are able to restore the functional activity of desensitized nAChR. RESULTS Screening of a virtual compound database of symmetrically substituted bispyridinium compounds with the derived pharmacophore yielded several promising compounds which satisfy the pharmacophore and ought to have the same or even better resensitizing effect on nAChR as the parent compound MB327.
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Affiliation(s)
- Thomas Wein
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universitat München, Butenandtstr, 5-13, 81377 Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universitat München, Butenandtstr, 5-13, 81377 Munich, Germany
| | - Sebastian Rappenglück
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universitat München, Butenandtstr, 5-13, 81377 Munich, Germany
| | - Sonja Sichler
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universitat München, Butenandtstr, 5-13, 81377 Munich, Germany
| | - Karin V Niessen
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937 Munich, Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937 Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937 Munich, Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstrasse 11, 80937 Munich, Germany
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Hauke TJ, Höfner G, Wanner KT. MS-Based Screening of 5-Substituted Nipecotic Acid Derived Hydrazone Libraries as Ligands of the GABA Transporter 1. ChemMedChem 2019; 14:583-593. [PMID: 30663849 DOI: 10.1002/cmdc.201800729] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/09/2019] [Indexed: 11/09/2022]
Abstract
A screening of compound libraries based on nipecotic acid derivatives with lipophilic residues attached to the scarcely explored 5-position of the core structure was used for the search of new inhibitors of the γ-aminobutyric acid (GABA) transporter 1 (mGAT1). The generated compound libraries, which were based on hydrazone chemistry commonly used in dynamic combinatorial chemistry but rendered pseudostatic, were screened for their binding affinities toward mGAT1 by means of MS Binding Assays. With nipecotic acid derived hydrazone rac-16 h [rac-(3R,5S)-{5-[(E)-2-{[5-(2-phenylethynyl)thiophen-2-yl]methylidene}hydrazin-1-yl]piperidine-3-carboxylic acid}-sodium chloride (1/2)], one hit was found and evaluated displaying sub-micromolar potency (pKi =6.62±0.04) and a noncompetitive interaction mode at mGAT1. By bearing a 5-(2-phenylethynyl)thiophen-2-yl residue attached to the 5-position of nipecotic acid via a three-atom spacer, compound rac-16 h contains a structural moiety so far unprecedented for these kinds of bioactive molecules, and complements novel 5-substituted nipecotic acid derived ligands of mGAT1 revealed in a recently published screening campaign. This new class of ligands, with an inhibition mode distinct from that of benchmark mGAT1 inhibitors, could serve as research tools for investigations of mGAT1-mediated GABA transport.
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Affiliation(s)
- Tobias J Hauke
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Georg Höfner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
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Tóth K, Höfner G, Wanner KT. Synthesis and biological evaluation of novel N-substituted nipecotic acid derivatives with a cis-alkene spacer as GABA uptake inhibitors. Bioorg Med Chem 2019; 27:822-831. [DOI: 10.1016/j.bmc.2019.01.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/15/2019] [Accepted: 01/23/2019] [Indexed: 10/27/2022]
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Kern F, Wanner KT. Screening oxime libraries by means of mass spectrometry (MS) binding assays: Identification of new highly potent inhibitors to optimized inhibitors γ-aminobutyric acid transporter 1. Bioorg Med Chem 2019; 27:1232-1245. [PMID: 30777661 DOI: 10.1016/j.bmc.2019.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 02/07/2019] [Indexed: 11/26/2022]
Abstract
Generation and screening of oxime libraries by competitive MS Binding Assays represents a powerful tool for the identification of new compounds, with affinity to mGAT1, the most abundant plasma membrane bound GABA transporter in the CNS. By screening a guvacine derived oxime library, new potent inhibitors of mGAT1 had been revealed. In the present study, oxime libraries generated by reaction of a large excess of a rac-nipecotic acid derivative displaying a hydroxylamine functionality in which various aldehydes under suitable conditions, were examined for new potent inhibitors of mGAT1. The pKi values obtained of the best hits were compared with those of related compounds displaying a guvacine instead of a nipecotic acid subunit as hydrophilic moiety. Amongst the new compounds one of the most affine ligands of mGAT1 known so far (pKi = 8.55 ± 0.04) was found.
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Affiliation(s)
- Felix Kern
- Department Pharmacy - Center for Drug Research, Ludwig-Maximilians-University München, Butenandtstr. 7, 81377 Munich, Germany
| | - Klaus T Wanner
- Department Pharmacy - Center for Drug Research, Ludwig-Maximilians-University München, Butenandtstr. 7, 81377 Munich, Germany.
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Hauke TJ, Höfner G, Wanner KT. Generation and screening of pseudostatic hydrazone libraries derived from 5-substituted nipecotic acid derivatives at the GABA transporter mGAT4. Bioorg Med Chem 2019; 27:144-152. [DOI: 10.1016/j.bmc.2018.11.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/29/2018] [Accepted: 11/20/2018] [Indexed: 10/27/2022]
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Huber SK, Höfner G, Wanner KT. Front Cover: Identification of Pyrrolidine‐3‐acetic Acid Derived Oximes as Potent Inhibitors of γ‐Aminobutyric Acid Transporter 1 through Library Screening with MS Binding Assays (ChemMedChem 23/2018). ChemMedChem 2018. [DOI: 10.1002/cmdc.201800740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Simone K. Huber
- Department of Pharmacy, Center of Drug ResearchLudwig Maximilians University of Munich Butenandtstr. 7 81377 Munich Germany
| | - Georg Höfner
- Department of Pharmacy, Center of Drug ResearchLudwig Maximilians University of Munich Butenandtstr. 7 81377 Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center of Drug ResearchLudwig Maximilians University of Munich Butenandtstr. 7 81377 Munich Germany
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Tóth K, Höfner G, Wanner KT. Synthesis and biological evaluation of novel N-substituted nipecotic acid derivatives with a trans-alkene spacer as potent GABA uptake inhibitors. Bioorg Med Chem 2018; 26:5944-5961. [DOI: 10.1016/j.bmc.2018.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 10/31/2018] [Accepted: 11/02/2018] [Indexed: 12/13/2022]
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Huber SK, Höfner G, Wanner KT. Identification of Pyrrolidine‐3‐acetic Acid Derived Oximes as Potent Inhibitors of γ‐Aminobutyric Acid Transporter 1 through Library Screening with MS Binding Assays. ChemMedChem 2018; 13:2488-2503. [DOI: 10.1002/cmdc.201800556] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Simone K. Huber
- Department of Pharmacy, Center of Drug ResearchLudwig Maximilians University of Munich Butenandtstr. 7 81377 Munich Germany
| | - Georg Höfner
- Department of Pharmacy, Center of Drug ResearchLudwig Maximilians University of Munich Butenandtstr. 7 81377 Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center of Drug ResearchLudwig Maximilians University of Munich Butenandtstr. 7 81377 Munich Germany
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Rappenglück S, Sichler S, Höfner G, Wein T, Niessen KV, Seeger T, Paintner FF, Worek F, Thiermann H, Wanner KT. Synthesis of a Series of Non-Symmetric Bispyridinium and Related Compounds and Their Affinity Characterization at the Nicotinic Acetylcholine Receptor. ChemMedChem 2018; 13:2653-2663. [DOI: 10.1002/cmdc.201800539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 09/28/2018] [Indexed: 01/24/2023]
Affiliation(s)
- Sebastian Rappenglück
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstrasse 5-13 81377 Munich Germany
| | - Sonja Sichler
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstrasse 5-13 81377 Munich Germany
| | - Georg Höfner
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstrasse 5-13 81377 Munich Germany
| | - Thomas Wein
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstrasse 5-13 81377 Munich Germany
| | - Karin V. Niessen
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstrasse 11 80937 Munich Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstrasse 11 80937 Munich Germany
| | - Franz F. Paintner
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstrasse 5-13 81377 Munich Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstrasse 11 80937 Munich Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstrasse 11 80937 Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstrasse 5-13 81377 Munich Germany
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32
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Hauke TJ, Wein T, Höfner G, Wanner KT. Novel Allosteric Ligands of γ-Aminobutyric Acid Transporter 1 (GAT1) by MS Based Screening of Pseudostatic Hydrazone Libraries. J Med Chem 2018; 61:10310-10332. [DOI: 10.1021/acs.jmedchem.8b01602] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Tobias J. Hauke
- Department of Pharmacy—Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Thomas Wein
- Department of Pharmacy—Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Georg Höfner
- Department of Pharmacy—Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 Munich, Germany
| | - Klaus T. Wanner
- Department of Pharmacy—Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 Munich, Germany
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Wein T, Höfner G, Rappenglück S, Sichler S, Niessen KV, Seeger T, Worek F, Thiermann H, Wanner KT. Searching for putative binding sites of the bispyridinium compound MB327 in the nicotinic acetylcholine receptor. Toxicol Lett 2018; 293:184-189. [DOI: 10.1016/j.toxlet.2017.10.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/18/2017] [Accepted: 10/29/2017] [Indexed: 01/14/2023]
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Rappenglück S, Sichler S, Höfner G, Wein T, Niessen KV, Seeger T, Paintner FF, Worek F, Thiermann H, Wanner KT. Synthesis of a Series of Structurally Diverse MB327 Derivatives and Their Affinity Characterization at the Nicotinic Acetylcholine Receptor. ChemMedChem 2018; 13:1806-1816. [DOI: 10.1002/cmdc.201800325] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/28/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Sebastian Rappenglück
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
| | - Sonja Sichler
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
| | - Georg Höfner
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
| | - Thomas Wein
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
| | - Karin V. Niessen
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstr. 11 80937 Munich Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstr. 11 80937 Munich Germany
| | - Franz F. Paintner
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstr. 11 80937 Munich Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology; Neuherbergstr. 11 80937 Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
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35
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Tóth K, Höfner G, Wanner KT. Synthesis and biological evaluation of novel N-substituted nipecotic acid derivatives with an alkyne spacer as GABA uptake inhibitors. Bioorg Med Chem 2018; 26:3668-3687. [DOI: 10.1016/j.bmc.2018.05.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 05/25/2018] [Accepted: 05/30/2018] [Indexed: 12/14/2022]
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Lutz T, Wein T, Höfner G, Pabel J, Eder M, Dine J, Wanner KT. Development of New Photoswitchable Azobenzene Based γ-Aminobutyric Acid (GABA) Uptake Inhibitors with Distinctly Enhanced Potency upon Photoactivation. J Med Chem 2018; 61:6211-6235. [DOI: 10.1021/acs.jmedchem.8b00629] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Toni Lutz
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Thomas Wein
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Georg Höfner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Jörg Pabel
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Matthias Eder
- Scientific Core Unit Electrophysiology, Max-Planck-Institut für Psychiatrie, Kraepelinstrasse 2-10, 80804 Munich, Germany
| | - Julien Dine
- Scientific Core Unit Electrophysiology, Department of Stress Neurobiology and Neurogenetics, Max-Planck-Institut für Psychiatrie, Kraepelinstrasse 2-10, 80804 Munich, Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University Munich, Butenandtstrasse 5-13, D-81377 Munich, Germany
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Neiens P, De Simone A, Ramershoven A, Höfner G, Allmendinger L, Wanner KT. Development and validation of an LC-ESI-MS/MS method for the quantification of D-84, reboxetine and citalopram for their use in MS Binding Assays addressing the monoamine transporters hDAT, hSERT and hNET. Biomed Chromatogr 2018; 32:e4231. [PMID: 29500932 DOI: 10.1002/bmc.4231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 01/10/2018] [Accepted: 02/26/2018] [Indexed: 02/05/2023]
Abstract
MS Binding Assays represent a label-free alternative to radioligand binding assays. In this study, we present an LC-ESI-MS/MS method for the quantification of (R,R)-4-(2-benzhydryloxyethyl)-1-(4-fluorobenzyl)piperidin-3-ol [(R,R)-D-84, (R,R)-1], (S,S)-reboxetine [(S,S)-2], and (S)-citalopram [(S)-3] employed as highly selective nonlabeled reporter ligands in MS Binding Assays addressing the dopamine [DAT, (R,R)-D-84], norepinephrine [NET, (S,S)-reboxetine] and serotonin transporter [SERT, (S)-citalopram], respectively. The developed LC-ESI-MS/MS method uses a pentafluorphenyl stationary phase in combination with a mobile phase composed of acetonitrile and ammonium formate buffer for chromatography and a triple quadrupole mass spectrometer in the multiple reaction monitoring mode for mass spectrometric detection. Quantification is based on deuterated derivatives of all three analytes serving as internal standards. The established LC-ESI-MS/MS method enables fast, robust, selective and highly sensitive quantification of all three reporter ligands in a single chromatographic run. The method was validated according to the Center for Drug Evaluation and Research (CDER) guideline for bioanalytical method validation regarding selectivity, accuracy, precision, calibration curve and sensitivity. Finally, filtration-based MS Binding Assays were performed for all three monoamine transporters based on this LC-ESI-MS/MS quantification method as read out. The affinities determined in saturation experiments for (R,R)-D-84 toward hDAT, for (S,S)-reboxetine toward hNET, and for (S)-citalopram toward hSERT, respectively, were in good accordance with results from literature, clearly demonstrating that the established MS Binding Assays have the potential to be an efficient alternative to radioligand binding assays widely used for this purpose so far.
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Affiliation(s)
- Patrick Neiens
- Department Pharmazie - Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Angela De Simone
- Department for Life Quality Studies, Alma Mater Studiorum - University of Bologna, Rimini, Italy
| | - Anna Ramershoven
- Department Pharmazie - Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Georg Höfner
- Department Pharmazie - Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Lars Allmendinger
- Department Pharmazie - Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Klaus T Wanner
- Department Pharmazie - Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, Munich, Germany
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38
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Neiens P, De Simone A, Höfner G, Wanner KT. Simultaneous Multiple MS Binding Assays for the Dopamine, Norepinephrine, and Serotonin Transporters. ChemMedChem 2018; 13:453-463. [PMID: 29451362 DOI: 10.1002/cmdc.201700737] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/10/2018] [Indexed: 12/17/2022]
Abstract
In this work, we present label-free, mass-spectrometry-based binding assays (MS Binding Assays), targeting the human dopamine, norepinephrine, and serotonin transporters (hDAT, hNET, and hSERT) in simultaneous binding experiments. Using a validated LC-ESI-MS/MS method for quantification of the selective dopamine transporter inhibitor (R,R)-4-(2-benzhydryloxyethyl)-1-(4-fluorobenzyl)piperidin-3-ol ((R,R)-D-84), the selective norepinephrine transporter inhibitor (S,S)-reboxetine, and the selective serotonin reuptake inhibitor (S)-citalopram, binding affinities at the three monoamine transporters could be characterized simultaneously in a single binding experiment. The performed simultaneous saturation and competition experiments yielded results that are in good accordance with those determined in MS Binding Assays addressing the monoamine transporters individually. The results obtained from this study underscore the potential of MS Binding Assays for simultaneous affinity determination at different targets, which is difficult to accomplish with conventional radioligand binding assays.
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Affiliation(s)
- Patrick Neiens
- Department of Pharmacy-Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Angela De Simone
- Department for Life Quality Studies, Alma Mater Studiorum-University of Bologna, Corso D'Augusto 237, 47921, Rimini, Italy
| | - Georg Höfner
- Department of Pharmacy-Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy-Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
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Scheffel C, Niessen KV, Rappenglück S, Wanner KT, Thiermann H, Worek F, Seeger T. Counteracting desensitization of human α7-nicotinic acetylcholine receptors with bispyridinium compounds as an approach against organophosphorus poisoning. Toxicol Lett 2017; 293:149-156. [PMID: 29248576 DOI: 10.1016/j.toxlet.2017.12.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 12/07/2017] [Accepted: 12/09/2017] [Indexed: 01/30/2023]
Abstract
Irreversible inhibition of acetylcholinesterase (AChE) resulting in accumulation of acetylcholine and overstimulation of muscarinic and nicotinic receptors accounts for the acute toxicity of organophosphorus compounds (OP). Accordingly, the mainstay pharmacotherapy against poisoning by OP comprises the competitive muscarinic acetylcholine receptor antagonist atropine to treat muscarinic effects and, in addition, oximes to reactivate inhibited AChE. A therapeutic gap still remains in the treatment of desensitized nicotinic acetylcholine receptors following OP exposure. Hereby, nicotinic effects result in paralysis of the central and peripheral respiratory system if untreated. Thus, these receptors pose an essential target for therapeutic indication to address these life-threatening nicotinic symptoms of the cholinergic crisis. Identification of ligands regulating dynamic transitions between functional states by binding to modulatory sites appears to be a promising strategy for therapeutic intervention. In this patch clamp study, the ability of differently substituted bispyridinium non-oximes to "resensitize" i.e. to recover the activity of desensitized human homomeric α7-type nAChRs stably transfected in CHO cells was investigated and compared to the already described α7-specific positive allosteric modulator PNU-120596. The structures of these bispyridinium analogues were based on the lead structure of the tert-butyl-substituted bispyridinium propane MB327, which has been shown to have a positive therapeutic effect due to a non-competitive antagonistic action at muscle-type nAChRs in vivo and has been found to have a positive allosteric activity at neuronal receptors in vitro. Prior to test compounds, desensitization of hα7-nAChRs was verified by applying an excess of nicotine revealing activation at low, and desensitization at high concentrations. Thereby, desensitization could be reduced by modulation with PNU-120596. Desensitization was further verified by dose-response profiles of agonists, carbamoylcholine and epibatidine in the absence and presence of PNU-120596. Although less pronounced than PNU-120596 and the lead structure MB327, bispyridinium compounds, particularly those substituted at position 3 and 4, resensitized the nicotine desensitized hα7-nAChRs in a concentration-dependent manner and prolonged the mean channel open time. In summary, identification of more potent compounds able to restore nAChR function in OP intoxication is needed for development of a putative efficient antidote.
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Affiliation(s)
- Corinna Scheffel
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Germany.
| | - Karin V Niessen
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | | | - Klaus T Wanner
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
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Sichler S, Höfner G, Rappenglück S, Wein T, Niessen KV, Seeger T, Worek F, Thiermann H, Paintner FF, Wanner KT. Development of MS Binding Assays targeting the binding site of MB327 at the nicotinic acetylcholine receptor. Toxicol Lett 2017; 293:172-183. [PMID: 29146291 DOI: 10.1016/j.toxlet.2017.11.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/09/2017] [Accepted: 11/12/2017] [Indexed: 02/06/2023]
Abstract
The bispyridinium compound MB327 has been shown previously to have a positive pharmacological effect against poisoning with organophosphorous compounds (OPCs). The mechanism by which it exerts its therapeutic effect seems to be directly mediated by the nicotinic acetylcholine receptor (nAChR). In the present study, the development of mass spectrometry based binding assays (MS Binding Assays) for characterization of the binding site of MB327 at the nAChR from Torpedo californica is described. MS Binding Assays follow the principle of radioligand binding assays, but do not, in contrast to the latter, require a radiolabeled reporter ligand, as the readout is in this case based on mass spectrometric detection. For [2H6]MB327, a deuterated MB327 analogue employed as reporter ligand in the MS Binding Assays, an LC-ESI-MS/MS method was established allowing for its fast and reliable quantification in samples resulting from binding experiments. Using centrifugation for separation of non-bound [2H6]MB327 from target-bound [2H6]MB327 in saturation and autocompetition experiments (employing native MB327 as competitor) enabled reliable determination of specific binding. In this way, the affinities for [2H6]MB327 (Kd=15.5±0.9μmolL-1) and for MB327 (Ki=18.3±2.6μmolL-1) towards the nAChR could be determined for the first time. The almost exactly matching affinities for MB327 and [2H6]MB327 obtained in the MS Binding Assays are in agreement with potencies previously found in functional studies. In summary, our results demonstrate that the established MS Binding Assays represent a promising tool for affinity determination of test compounds towards the binding site of MB327 at the nAChR.
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Affiliation(s)
- S Sichler
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 Munich, Germany
| | - G Höfner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 Munich, Germany
| | - S Rappenglück
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 Munich, Germany
| | - T Wein
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 Munich, Germany
| | - K V Niessen
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany
| | - T Seeger
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany
| | - F Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany
| | - H Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80937 Munich, Germany
| | - F F Paintner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 Munich, Germany
| | - K T Wanner
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 Munich, Germany.
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Schuller M, Höfner G, Wanner KT. Corrigendum: Simultaneous Multiple MS Binding Assays Addressing D 1
and D 2
Dopamine Receptors. ChemMedChem 2017; 12:1737. [DOI: 10.1002/cmdc.201700588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Schuller M, Höfner G, Wanner KT. Front Cover: Simultaneous Multiple MS Binding Assays Addressing D 1
and D 2
Dopamine Receptors (ChemMedChem 19/2017). ChemMedChem 2017. [DOI: 10.1002/cmdc.201700580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marion Schuller
- Structural Genomics Consortium and Target Discovery Institute, Nuffield Department of Clinical Medicine; University of Oxford; Oxford OX3 7FZ UK
| | - Georg Höfner
- Department of Pharmacy, Center of Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center of Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 5-13 81377 Munich Germany
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Schuller M, Höfner G, Wanner KT. Simultaneous Multiple MS Binding Assays Addressing D 1 and D 2 Dopamine Receptors. ChemMedChem 2017; 12:1585-1594. [PMID: 28776962 DOI: 10.1002/cmdc.201700369] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 07/27/2017] [Indexed: 01/08/2023]
Abstract
MS Binding Assays are a label-free alternative to radioligand binding assays. They provide basically the same capabilities as the latter, but use a non-labeled reporter ligand instead of a radioligand. In contrast to radioligand binding assays, MS Binding Assays offer-owing to the selectivity of mass spectrometric detection-the opportunity to monitor the binding of different reporter ligands at different targets simultaneously. The present study shows a proof of concept for this strategy as exemplified for MS Binding Assays selectively addressing D1 and D2 dopamine receptors in a single binding experiment. A highly sensitive, rapid and robust LC-ESI-MS/MS quantification method capable of quantifying both SCH23390 and raclopride, selectively addressing D1 and D2 receptors, respectively, was established and validated for this purpose. Based thereon, simultaneous saturation and competition experiments with SCH23390 and raclopride in the presence of both D1 and D2 receptors were performed and analyzed by LC-MS/MS within a single chromatographic cycle. The present study thus demonstrates the feasibility of this strategy and the high versatility of MS Binding Assays that appears to surpass that common for conventional radioligand binding assays.
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Affiliation(s)
- Marion Schuller
- Structural Genomics Consortium and Target Discovery Institute, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7FZ, UK
| | - Georg Höfner
- Department of Pharmacy, Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Klaus T Wanner
- Department of Pharmacy, Center of Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377, Munich, Germany
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Affiliation(s)
- Maren Schaarschmidt
- Department of Pharmacy, Center
for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Klaus T. Wanner
- Department of Pharmacy, Center
for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, D-81377 Munich, Germany
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Neiens P, Höfner G, Wanner KT. Determination of the enantiomeric purity of the selective dopamine transporter inhibitor (+)-R,R
-4-(2-benzhydryloxyethyl)-1-(4-fluorobenzyl)piperidin-3-ol. Chirality 2017; 29:294-303. [DOI: 10.1002/chir.22688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/07/2017] [Accepted: 02/22/2017] [Indexed: 01/11/2023]
Affiliation(s)
- Patrick Neiens
- Department Pharmazie - Zentrum für Pharmaforschung; Ludwig-Maximilians-Universität München; Munich Germany
| | - Georg Höfner
- Department Pharmazie - Zentrum für Pharmaforschung; Ludwig-Maximilians-Universität München; Munich Germany
| | - Klaus T. Wanner
- Department Pharmazie - Zentrum für Pharmaforschung; Ludwig-Maximilians-Universität München; Munich Germany
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Lutz T, Wein T, Höfner G, Wanner KT. Development of Highly Potent GAT1 Inhibitors: Synthesis of Nipecotic Acid Derivatives withN-Arylalkynyl Substituents. ChemMedChem 2017; 12:362-371. [DOI: 10.1002/cmdc.201600599] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/20/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Toni Lutz
- Department for Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 7-13 81377 Munich Germany
| | - Thomas Wein
- Department for Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 7-13 81377 Munich Germany
| | - Georg Höfner
- Department for Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 7-13 81377 Munich Germany
| | - Klaus T. Wanner
- Department for Pharmacy, Center for Drug Research; Ludwig-Maximilians-Universität München; Butenandtstr. 7-13 81377 Munich Germany
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Schmidt SK, Höfner G, Wanner KT. Cover Image, Volume 29, Issue 1. Chirality 2017. [DOI: 10.1002/chir.22676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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48
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Schmidt SK, Höfner G, Wanner KT. Determination of enantiomeric excess of nipecotic acid as 1-(7-nitrobenzo[c][1,2,5]oxadiazol-4-yl) derivatives. Chirality 2016; 29:48-56. [DOI: 10.1002/chir.22670] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 11/04/2016] [Accepted: 11/07/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Simone K. Schmidt
- Department of Pharmacy - Center of Drug Research; Ludwig-Maximilians-Universität München; Munich Germany
| | - Georg Höfner
- Department of Pharmacy - Center of Drug Research; Ludwig-Maximilians-Universität München; Munich Germany
| | - Klaus T. Wanner
- Department of Pharmacy - Center of Drug Research; Ludwig-Maximilians-Universität München; Munich Germany
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Sohail A, Jayaraman K, Venkatesan S, Gotfryd K, Daerr M, Gether U, Loland CJ, Wanner KT, Freissmuth M, Sitte HH, Sandtner W, Stockner T. The Environment Shapes the Inner Vestibule of LeuT. PLoS Comput Biol 2016; 12:e1005197. [PMID: 27835643 PMCID: PMC5105988 DOI: 10.1371/journal.pcbi.1005197] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 10/12/2016] [Indexed: 12/27/2022] Open
Abstract
Human neurotransmitter transporters are found in the nervous system terminating synaptic signals by rapid removal of neurotransmitter molecules from the synaptic cleft. The homologous transporter LeuT, found in Aquifex aeolicus, was crystallized in different conformations. Here, we investigated the inward-open state of LeuT. We compared LeuT in membranes and micelles using molecular dynamics simulations and lanthanide-based resonance energy transfer (LRET). Simulations of micelle-solubilized LeuT revealed a stable and widely open inward-facing conformation. However, this conformation was unstable in a membrane environment. The helix dipole and the charged amino acid of the first transmembrane helix (TM1A) partitioned out of the hydrophobic membrane core. Free energy calculations showed that movement of TM1A by 0.30 nm was driven by a free energy difference of ~15 kJ/mol. Distance measurements by LRET showed TM1A movements, consistent with the simulations, confirming a substantially different inward-open conformation in lipid bilayer from that inferred from the crystal structure. Crystal structures of the bacterial small amino acid transporter LeuT provided structural evidence for the alternating access model. Thereby, these structures shaped our understanding of the mechanisms underlying substrate translocation by neurotransmitter transporters. However, it has been questioned, if the crystallized inward-open conformation of LeuT can exist in the membrane environment. Here we show that, while stable in detergent micelles, the inward-open conformation of LeuT is of high energy and undergoes structural readjustments. We use a multi-faceted approach including molecular dynamics simulations, scintillation proximity assays, free energy calculations and apply for the first time lanthanide resonance energy transfer measurements to verify the in silico predictions. In silico and in vitro approaches using the same conditions allowed us to combine the macroscopic experimental data with microscopic all atom results from simulations to identify the underlying driving forces: partitioning of charged and polar groups from the hydrophobic membrane interior to the hydrophilic environment. We propose that the inward-facing state shows a much smaller movement of TM1A, but large enough to create an access path to the S1 substrate binding site from the vestibule.
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Affiliation(s)
- Azmat Sohail
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
| | - Kumaresan Jayaraman
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
| | - Santhoshkannan Venkatesan
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
| | - Kamil Gotfryd
- University of Copenhagen, Faculty of Health and Medical Sciences Denmark, Department of Neuroscience and Pharmacology, Copenhagen, Denmark
- University of Copenhagen, Faculty of Health Sciences Denmark, Department of Biomedical Sciences, Copenhagen, Denmark
| | - Markus Daerr
- Ludwig Maximilians University Munich, Department of Pharmacy, Center of Drug Research, Munich, Germany
| | - Ulrik Gether
- University of Copenhagen, Faculty of Health and Medical Sciences Denmark, Department of Neuroscience and Pharmacology, Copenhagen, Denmark
| | - Claus J. Loland
- University of Copenhagen, Faculty of Health and Medical Sciences Denmark, Department of Neuroscience and Pharmacology, Copenhagen, Denmark
| | - Klaus T. Wanner
- Ludwig Maximilians University Munich, Department of Pharmacy, Center of Drug Research, Munich, Germany
| | - Michael Freissmuth
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
| | - Harald H. Sitte
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
- * E-mail:
| | - Walter Sandtner
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
| | - Thomas Stockner
- Medical University of Vienna, Center for Physiology and Pharmacology, Institute of Pharmacology, Vienna, Austria
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Cattaneo G, Ubiali D, Calleri E, Rabuffetti M, Höfner GC, Wanner KT, De Moraes MC, Martinelli LK, Santos DS, Speranza G, Massolini G. Development, validation and application of a 96-well enzymatic assay based on LC-ESI-MS/MS quantification for the screening of selective inhibitors against Mycobacterium tuberculosis purine nucleoside phosphorylase. Anal Chim Acta 2016; 943:89-97. [DOI: 10.1016/j.aca.2016.09.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 09/07/2016] [Accepted: 09/15/2016] [Indexed: 01/08/2023]
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