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Milani G, Budriesi R, Tavazzani E, Cavalluzzi MM, Mattioli LB, Miniero DV, Delre P, Belviso BD, Denegri M, Cuocci C, Rotondo NP, De Palma A, Gualdani R, Caliandro R, Mangiatordi GF, Kumawat A, Camilloni C, Priori S, Lentini G. hERG stereoselective modulation by mexiletine-derived ureas: Molecular docking study, synthesis, and biological evaluation. Arch Pharm (Weinheim) 2023; 356:e2300116. [PMID: 37460390 DOI: 10.1002/ardp.202300116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 10/06/2023]
Abstract
Long QT syndrome (LQTS) is a disorder of cardiac electrophysiology resulting in life-threatening arrhythmias; nowadays, only a few drugs are available for the management of LQTS. Focusing our attention on LQT2, one of the most common subtypes of LQTS caused by mutations in the human ether-à-go-go-related gene (hERG), in the present work, the stereoselectivity of the recently discovered mexiletine-derived urea 8 was investigated on the hERG potassium channel. According to preliminary in silico predictions, in vitro studies revealed a stereoselective behavior, with the meso form showing the greatest hERG opening activity. In addition, functional studies on guinea pig isolated left atria, aorta, and ileum demonstrated that 8 does not present any cardiac or intestinal liability in our ex vivo studies. Due to its overall profile, (R,S)-8 paves the way for the design and development of a new series of compounds potentially useful in the treatment of both congenital and drug-induced forms of LQTS.
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Affiliation(s)
- Gualtiero Milani
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Roberta Budriesi
- Department of Pharmacy and Biotechnology, Food Chemistry and Nutraceutical Lab, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | | | | | - Laura Beatrice Mattioli
- Department of Pharmacy and Biotechnology, Food Chemistry and Nutraceutical Lab, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Daniela Valeria Miniero
- Department of Biosciences, Biotechnologies, and Environment, University Aldo Moro of Bari, Bari, Italy
| | - Pietro Delre
- Chemistry Department, University of Bari Aldo Moro, Bari, Italy
- CNR-Institute of Crystallography, Bari, Italy
| | | | | | | | - Natalie Paola Rotondo
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Annalisa De Palma
- Department of Biosciences, Biotechnologies, and Environment, University Aldo Moro of Bari, Bari, Italy
| | - Roberta Gualdani
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | | | | | - Amit Kumawat
- Department of Biosciences, University of Milan, Milano, Italy
| | - Carlo Camilloni
- Department of Biosciences, University of Milan, Milano, Italy
| | - Silvia Priori
- ICS-Maugeri IRCCS, Pavia, Italy
- Molecular Cardiology, Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
| | - Giovanni Lentini
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy
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Milani G, Cavalluzzi MM, Altamura C, Santoro A, Perrone M, Muraglia M, Colabufo NA, Corbo F, Casalino E, Franchini C, Pisano I, Desaphy J, Carrieri A, Carocci A, Lentini G. Bioisosteric Modification of To042: Synthesis and Evaluation of Promising Use-Dependent Inhibitors of Voltage-Gated Sodium Channels. ChemMedChem 2021; 16:3588-3599. [PMID: 34519427 PMCID: PMC9293070 DOI: 10.1002/cmdc.202100496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/01/2021] [Indexed: 11/07/2022]
Abstract
Three analogues of To042, a tocainide-related lead compound recently reported for the treatment of myotonia, were synthesized and evaluated in vitro as skeletal muscle sodium channel blockers possibly endowed with enhanced use-dependent behavior. Patch-clamp experiments on hNav1.4 expressed in HEK293 cells showed that N-[(naphthalen-1-yl)methyl]-4-[(2,6-dimethyl)phenoxy]butan-2-amine, the aryloxyalkyl bioisostere of To042, exerted a higher use-dependent block than To042 thus being able to preferentially block the channels in over-excited membranes while preserving healthy tissue function. It also showed the lowest active transport across BBB according to the results of P-glycoprotein (P-gp) interacting activity evaluation and the highest cytoprotective effect on HeLa cells. Quantum mechanical calculations and dockings gave insights on the most probable conformation of the aryloxyalkyl bioisostere of To042 in solution and the target residues involved in the binding, respectively. Both approaches indicated the conformations that might be adopted in both the unbound and bound state of the ligand. Overall, N-[(naphthalen-1-yl)methyl]-4-[(2,6-dimethyl)phenoxy]butan-2-amine exhibits an interesting toxico-pharmacological profile and deserves further investigation.
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Affiliation(s)
- Gualtiero Milani
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Maria Maddalena Cavalluzzi
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Concetta Altamura
- Department of Biomedical Sciences and Human OncologySchool of MedicineUniversity of Bari Aldo Moro PoliclinicoPiazza Giulio Cesare70124BariItaly
| | - Antonella Santoro
- Department of Bioscience, Biotechnology and BiopharmaceuticsUniversity of Bari Aldo MoroVia Orabona 470125BariItaly
| | - Mariagrazia Perrone
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Marilena Muraglia
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Nicola Antonio Colabufo
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Filomena Corbo
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Elisabetta Casalino
- Department of Veterinary MedicineUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Carlo Franchini
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Isabella Pisano
- Department of Bioscience, Biotechnology and BiopharmaceuticsUniversity of Bari Aldo MoroVia Orabona 470125BariItaly
| | - Jean‐François Desaphy
- Department of Biomedical Sciences and Human OncologySchool of MedicineUniversity of Bari Aldo Moro PoliclinicoPiazza Giulio Cesare70124BariItaly
| | - Antonio Carrieri
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Alessia Carocci
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
| | - Giovanni Lentini
- Department of Pharmacy – Pharmaceutical SciencesUniversity of Bari Aldo MoroVia E. Orabona 470125BariItaly
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3
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Catalano A, Franchini C, Carocci A. Voltage-Gated Sodium Channel Blockers: Synthesis of Mexiletine Analogues and Homologues. Curr Med Chem 2021; 28:1535-1548. [PMID: 32364065 DOI: 10.2174/0929867327666200504080530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 03/13/2020] [Accepted: 03/14/2020] [Indexed: 11/22/2022]
Abstract
Mexiletine is an antiarrhythmic drug belonging to IB class, acting as sodium channel blocker. Besides its well-known activity on arrhythmias, its usefulness in the treatment of myotonia, myotonic dystrophy and amyotrophic lateral sclerosis is now widely recognized. Nevertheless, it has been retired from the market in several countries because of its undesired effects. Thus, several papers were reported in the last years about analogues and homologues of mexiletine being endowed with a wider therapeutic ratio and a more selectivity of action. Some of them showed sodium channel blocking activity higher than the parent compound. It is noteworthy that mexiletine is used in therapy as a racemate even though a difference in the activities of the two enantiomers was widely demonstrated, with (-)-(R)-enantiomer being more active: this finding led several research groups to study mexiletine and its analogues and homologues in their optically active forms. This review summarizes the different synthetic routes used to obtain these compounds. They could represent an interesting starting point to new mexiletine-like compounds without common side effects related to the use of mexiletine.
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Affiliation(s)
- Alessia Catalano
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", via Orabona 4, 70126 Bari, Italy
| | - Carlo Franchini
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", via Orabona 4, 70126 Bari, Italy
| | - Alessia Carocci
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", via Orabona 4, 70126 Bari, Italy
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Iacopetta D, Carocci A, Sinicropi MS, Catalano A, Lentini G, Ceramella J, Curcio R, Caroleo MC. Old Drug Scaffold, New Activity: Thalidomide-Correlated Compounds Exert Different Effects on Breast Cancer Cell Growth and Progression. ChemMedChem 2017; 12:381-389. [PMID: 28099781 DOI: 10.1002/cmdc.201600629] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 01/16/2017] [Indexed: 12/17/2022]
Abstract
Thalidomide was first used for relief of morning sickness in pregnant women and then withdrawn from the market because of its dramatic effects on normal fetal development. Over the last decades, it has been used successfully for the treatment of several pathologies, including cancer. Many analogues with improved activity have been synthesized and tested. Herein we report some effects on the growth and progression of MCF-7 and MDA-MB-231 breast cancer cells by a small series of thalidomide-correlated compounds, which are very effective at inducing cancer cell death by triggering TNFα-mediated apoptosis. The most active compounds are able to drastically reduce the migration of breast cancer cells by regulation of the two major proteins involved in epithelial-mesenchymal transition (EMT): vimentin and E-cadherin. Moreover, these compounds diminish the intracellular biosynthesis of vascular endothelial growth factor (VEGF), which is primarily involved in the promotion of angiogenesis, sustaining tumor progression. The multiple features of these compounds that act on various key points of the tumorigenesis process make them good candidates for preclinical studies.
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Affiliation(s)
- Domenico Iacopetta
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036, Arcavacata di Rende, Italy
| | - Alessia Carocci
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70126, Bari, Italy
| | - Maria Stefania Sinicropi
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036, Arcavacata di Rende, Italy
| | - Alessia Catalano
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70126, Bari, Italy
| | - Giovanni Lentini
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", 70126, Bari, Italy
| | - Jessica Ceramella
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036, Arcavacata di Rende, Italy
| | - Rosita Curcio
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036, Arcavacata di Rende, Italy
| | - Maria Cristina Caroleo
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036, Arcavacata di Rende, Italy
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Catalano A, Luciani R, Carocci A, Cortesi D, Pozzi C, Borsari C, Ferrari S, Mangani S. X-ray crystal structures of Enterococcus faecalis thymidylate synthase with folate binding site inhibitors. Eur J Med Chem 2016; 123:649-664. [PMID: 27517810 DOI: 10.1016/j.ejmech.2016.07.066] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 11/26/2022]
Abstract
Infections caused by Enterococcus faecalis (Ef) represent nowadays a relevant health problem. We selected Thymidylate synthase (TS) from this organism as a potential specific target for antibacterial therapy. We have previously demonstrated that species-specific inhibition of the protein can be achieved despite the relatively high structural similarity among bacterial TSs and human TS. We had previously obtained the EfTS crystal structure of the protein in complex with the metabolite 5-formyl-tetrahydrofolate (5-FTHF) suggesting the protein role as metabolite reservoir; however, protein-inhibitors complexes were still missing. In the present work we identified some inhibitors bearing the phthalimidic core from our in-house library and we performed crystallographic screening towards EfTS. We obtained two X-ray crystallographic structures: the first with a weak phthalimidic inhibitor bound in one subunit and 5-hydroxymethylene-6-hydrofolic acid (5-HMHF) in the other subunit; a second X-ray structure complex with methotrexate. The structural information achieved confirm the role of EfTS as an enzyme involved in the folate pool system and provide a structural basis for structure-based drug design.
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Affiliation(s)
- Alessia Catalano
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari "Aldo Moro", Via Orabona 4, 70125 Bari, Italy
| | - Rosaria Luciani
- Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Alessia Carocci
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari "Aldo Moro", Via Orabona 4, 70125 Bari, Italy
| | - Debora Cortesi
- Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Cecilia Pozzi
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Chiara Borsari
- Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Stefania Ferrari
- Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Via Campi 103, 41125 Modena, Italy.
| | - Stefano Mangani
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, Via Aldo Moro 2, 53100 Siena, Italy.
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Synthesis, antiarrhythmic activity, and toxicological evaluation of mexiletine analogues. Eur J Med Chem 2016; 121:300-307. [PMID: 27267000 DOI: 10.1016/j.ejmech.2016.05.046] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/20/2016] [Accepted: 05/21/2016] [Indexed: 11/24/2022]
Abstract
Four mexiletine analogues have been tested for their antiarrhythmic, inotropic, and chronotropic effects on isolated guinea pig heart tissues and to assess calcium antagonist activity, in comparison with the parent compound mexiletine. All analogues showed from moderate to high antiarrhythmic activity. In particular, three of them (1b,c,e) were more active and potent than the reference drug, while exhibiting only modest or no negative inotropic and chronotropic effects and vasorelaxant activity, thus showing high selectivity of action. All compounds showed no cytotoxicity and 1b,c,d did not impair motor coordination. All in, these new analogues exhibit an interesting cardiovascular profile and deserve further investigation.
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Antiproliferative Activity Evaluation of a Series ofN-1,3-Benzothiazol-2-ylbenzamides as Novel Apoptosis Inducers. J CHEM-NY 2016. [DOI: 10.1155/2016/4267564] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
A series ofN-1,3-benzothiazol-2-ylbenzamide derivatives were studied for their antiproliferative activity on human liver hepatocellular carcinoma (HepG2) and human breast cancer (MCF-7) cell lines. Most of them were found to show a prominent inhibitory effect on cell growth. Among the most active compounds,1kemerged for its proapoptotic effect that is particularly evident towards MCF-7 cancer cell lines.
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Chau BA, Drummond G, Jackson WR, Jarrott B, Miller AA, Subasinghe KR, Tan CYR, White PJ, Wright CE, Ziogas J. Synthesis of six mexiletine derivatives with isoindolines attached as potential antioxidants and their evaluation as cardioprotective agents. MEDCHEMCOMM 2015. [DOI: 10.1039/c4md00459k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Some mexiletine derivatives with isoindoline based antioxidants attached have been shown to have significant cardioprotective properties.
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Affiliation(s)
- Bich Anh Chau
- ARC Centre for Free Radical Chemistry & Biotechnology
- Australia
- Centre for Green Chemistry
- Monash University
- Clayton
| | - Grant Drummond
- Department of Pharmacology
- Monash University
- Clayton
- Australia
| | - W. Roy Jackson
- ARC Centre for Free Radical Chemistry & Biotechnology
- Australia
- Centre for Green Chemistry
- Monash University
- Clayton
| | - Bevyn Jarrott
- The Florey Institute of Neuroscience and Mental Health
- The University of Melbourne
- Australia
| | | | - Kamani R. Subasinghe
- ARC Centre for Free Radical Chemistry & Biotechnology
- Australia
- Centre for Green Chemistry
- Monash University
- Clayton
| | - Christina Y. R. Tan
- Medicinal Chemistry and Drug Action
- Monash Institute of Pharmaceutical Sciences
- Monash University
- Parkville
- Australia
| | - Paul J. White
- Medicinal Chemistry and Drug Action
- Monash Institute of Pharmaceutical Sciences
- Monash University
- Parkville
- Australia
| | - Christine E. Wright
- ARC Centre for Free Radical Chemistry & Biotechnology
- Australia
- Department of Pharmacology & Therapeutics
- The University of Melbourne
- Australia
| | - James Ziogas
- ARC Centre for Free Radical Chemistry & Biotechnology
- Australia
- Department of Pharmacology & Therapeutics
- The University of Melbourne
- Australia
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Muraglia M, De Bellis M, Catalano A, Carocci A, Franchini C, Carrieri A, Fortugno C, Bertucci C, Desaphy JF, De Luca A, Conte Camerino D, Corbo F. N-aryl-2,6-dimethylbenzamides, a new generation of tocainide analogues as blockers of skeletal muscle voltage-gated sodium channels. J Med Chem 2014; 57:2589-600. [PMID: 24568674 DOI: 10.1021/jm401864b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
On the basis of a 3D-QSAR study, a new generation of tocainide analogues were designed and synthesized as voltage-gated skeletal muscle sodium channel blockers. Data obtained by screening new compounds by means of Hille-Campbell Vaseline gap voltage-clamp recordings showed that the elongation of the alkyl chain and the introduction of lipophilic and sterically hindered groups on the amino function enhance both potency and use-dependent block. The results provide additional indications about the structural requirement of pharmacophores for further increasing potency and state-dependent block and allowed us to identify a new tocainide analogue (6f) with a favorable pharmacodynamic profile to be proposed as a valid candidate for studies aimed at evaluating its usefulness in the treatment of myotonias.
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Affiliation(s)
- Marilena Muraglia
- Dipartimento di Farmacia-Scienze del Farmaco, ‡Sezione di Farmacologia, Università degli Studi di Bari "Aldo Moro" , via E. Orabona n. 4, 70126 Bari, Italy
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Searching for new antiarrhythmic agents: Evaluation of meta-hydroxymexiletine enantiomers. Eur J Med Chem 2013; 65:511-6. [DOI: 10.1016/j.ejmech.2013.05.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 05/02/2013] [Accepted: 05/10/2013] [Indexed: 11/23/2022]
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Desaphy JF, Dipalma A, Costanza T, Carbonara R, Dinardo MM, Catalano A, Carocci A, Lentini G, Franchini C, Camerino DC. Molecular Insights into the Local Anesthetic Receptor within Voltage-Gated Sodium Channels Using Hydroxylated Analogs of Mexiletine. Front Pharmacol 2012; 3:17. [PMID: 22403541 PMCID: PMC3279704 DOI: 10.3389/fphar.2012.00017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 01/30/2012] [Indexed: 12/26/2022] Open
Abstract
We previously showed that the β-adrenoceptor modulators, clenbuterol and propranolol, directly blocked voltage-gated sodium channels, whereas salbutamol and nadolol did not (Desaphy et al., 2003), suggesting the presence of two hydroxyl groups on the aromatic moiety of the drugs as a molecular requisite for impeding sodium channel block. To verify such an hypothesis, we synthesized five new mexiletine analogs by adding one or two hydroxyl groups to the aryloxy moiety of the sodium channel blocker and tested these compounds on hNav1.4 channels expressed in HEK293 cells. Concentration–response relationships were constructed using 25-ms-long depolarizing pulses at −30 mV applied from an holding potential of −120 mV at 0.1 Hz (tonic block) and 10 Hz (use-dependent block) stimulation frequencies. The half-maximum inhibitory concentrations (IC50) were linearly correlated to drug lipophilicity: the less lipophilic the drug, minor was the block. The same compounds were also tested on F1586C and Y1593C hNav1.4 channel mutants, to gain further information on the molecular interactions of mexiletine with its receptor within the sodium channel pore. In particular, replacement of Phe1586 and Tyr1593 by non-aromatic cysteine residues may help in the understanding of the role of π–π or π–cation interactions in mexiletine binding. Alteration of tonic block suggests that the aryloxy moiety of mexiletine may interact either directly or indirectly with Phe1586 in the closed sodium channel to produce low-affinity binding block, and that this interaction depends on the electrostatic potential of the drug aromatic tail. Alteration of use-dependent block suggests that addition of hydroxyl groups to the aryloxy moiety may modify high-affinity binding of the drug amine terminal to Phe1586 through cooperativity between the two pharmacophores, this effect being mainly related to drug lipophilicity. Mutation of Tyr1593 further impaired such cooperativity. In conclusion, these results confirm our former hypothesis by showing that the presence of hydroxyl groups to the aryloxy moiety of mexiletine greatly reduced sodium channel block, and provide molecular insights into the intimate interaction of local anesthetics with their receptor.
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Affiliation(s)
- Jean-François Desaphy
- Section of Pharmacology, Department of Pharmacobiology, Faculty of Pharmacy, University of Bari Bari, Italy
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