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Ashraf A, Ahmed A, Juffer AH, Carter WG. An In Vivo and In Silico Approach Reveals Possible Sodium Channel Nav1.2 Inhibitors from Ficus religiosa as a Novel Treatment for Epilepsy. Brain Sci 2024; 14:545. [PMID: 38928545 PMCID: PMC11202011 DOI: 10.3390/brainsci14060545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 05/24/2024] [Accepted: 05/24/2024] [Indexed: 06/28/2024] Open
Abstract
Epilepsy is a neurological disease that affects approximately 50 million people worldwide. Despite an existing abundance of antiepileptic drugs, lifelong disease treatment is often required but could be improved with alternative drugs that have fewer side effects. Given that epileptic seizures stem from abnormal neuronal discharges predominately modulated by the human sodium channel Nav1.2, the quest for novel and potent Nav1.2 blockers holds promise for epilepsy management. Herein, an in vivo approach was used to detect new antiepileptic compounds using the maximum electroshock test on mice. Pre-treatment of mice with extracts from the Ficus religiosa plant ameliorated the tonic hind limb extensor phase of induced convulsions. Subsequently, an in silico approach identified potential Nav1.2 blocking compounds from F. religiosa using a combination of computational techniques, including molecular docking, prime molecular mechanics/generalized Born surface area (MM/GBSA) analysis, and molecular dynamics (MD) simulation studies. The molecular docking and MM/GBSA analysis indicated that out of 82 compounds known to be present in F. religiosa, seven exhibited relatively strong binding affinities to Nav1.2 that ranged from -6.555 to -13.476 kcal/mol; similar or with higher affinity than phenytoin (-6.660 kcal/mol), a known Na+-channel blocking antiepileptic drug. Furthermore, MD simulations revealed that two compounds: 6-C-glucosyl-8-C-arabinosyl apigenin and pelargonidin-3-rhamnoside could form stable complexes with Nav1.2 at 300 K, indicating their potential as lead antiepileptic agents. In summary, the combination of in vivo and in silico approaches supports the potential of F. religiosa phytochemicals as natural antiepileptic therapeutic agents.
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Affiliation(s)
- Aqsa Ashraf
- Faculty of Pharmacy, Punjab University College of Pharmacy, University of the Punjab, Lahore 54590, Pakistan;
| | - Abrar Ahmed
- Faculty of Pharmacy, Punjab University College of Pharmacy, University of the Punjab, Lahore 54590, Pakistan;
| | - André H. Juffer
- Biocentre Oulu (BCO) and Faculty of Biochemistry and Molecular Medicine (FBMM), University of Oulu, 90570 Oulu, Finland;
| | - Wayne G. Carter
- Clinical Toxicology Research Group, School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Derby DE22 3DT, UK
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2
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Stilley SE, Naraine AS, Yadavalli KP, Maki SL, Jutte EM, Kahn JM, Surtel AA, Lepore SD, Dawson-Scully K. Bridged bicyclic compounds: Comprehending a novel compound class as potential anti-seizure agents. Epilepsia 2023; 64:2958-2967. [PMID: 37660326 PMCID: PMC10840942 DOI: 10.1111/epi.17769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/29/2023] [Accepted: 08/29/2023] [Indexed: 09/05/2023]
Abstract
OBJECTIVE In the present study, we describe a novel class of small-molecule synthetic compounds that ameliorate seizure-like behavior, using an electroshock assay to examine seizure duration in Caenorhabditis elegans. We also examine the hypothesis that these compounds, which we have called resveramorphs (RVMs), act by an irreversible binding mechanism. METHODS Our electroshock assay examines seizure duration in C. elegans and can be used as a drug-screening platform for the identification of novel anti-seizure agents. The use of C. elegans allows for a rapid and efficient method of drug screening that may take years in other higher-order model organisms. A novel wash method, paired with our electroshock assay, allows us to discern differences in biological activity when the C. elegans are incubated in different drug solutions, to establish whether these compounds can be "washed" off. RESULTS One of the RVMs (RVM-3), reported here for the first time, was found to be potent at picomolar concentrations. Insights also provided information on the potential mechanisms of action of this compound. Covalent binding is thought to provide a strong irreversible bond because of a change in structure between two of the novel RVMs described in this work. This was also discerned through the novel wash method paired with our electroshock assay. SIGNIFICANCE RVM-3 was evaluated using our assay and found to possess anti-seizure activity at picomolar concentrations. These insights also provide information on the potential mechanisms of action of these compounds, which may include covalent binding. This was also discerned through a novel wash method paired with our electroshock assay.
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Affiliation(s)
- Samantha E. Stilley
- Department of Biology, Charles E. Schmidt College of
Science, Florida Atlantic University, Boca Raton, FL
| | - Akshay S. Naraine
- Department of Biology, Charles E. Schmidt College of
Science, Florida Atlantic University, Boca Raton, FL
- IMPRS for Synapses and Circuits, Max Planck Florida
Institute for Neuroscience, Jupiter, FL
| | - Krishna P. Yadavalli
- Department of Chemistry and Biochemistry, Charles E.
Schmidt College of Science, Florida Atlantic University, Boca Raton, FL
| | - Samantha L. Maki
- Department of Chemistry and Biochemistry, Charles E.
Schmidt College of Science, Florida Atlantic University, Boca Raton, FL
| | - Elyse M. Jutte
- Department of Chemistry and Biochemistry, Charles E.
Schmidt College of Science, Florida Atlantic University, Boca Raton, FL
| | - Jared M. Kahn
- Department of Chemistry and Biochemistry, Charles E.
Schmidt College of Science, Florida Atlantic University, Boca Raton, FL
| | - Alexis A. Surtel
- Department of Biology, Charles E. Schmidt College of
Science, Florida Atlantic University, Boca Raton, FL
| | - Salvatore D. Lepore
- IMPRS for Synapses and Circuits, Max Planck Florida
Institute for Neuroscience, Jupiter, FL
| | - Ken Dawson-Scully
- Department of Biology, Charles E. Schmidt College of
Science, Florida Atlantic University, Boca Raton, FL
- Department of Psychology and Neuroscience, College of
Psychology, Nova Southeastern University, Davie, FL
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Xie X, Yu T, Li X, Zhang N, Foster LJ, Peng C, Huang W, He G. Recent advances in targeting the "undruggable" proteins: from drug discovery to clinical trials. Signal Transduct Target Ther 2023; 8:335. [PMID: 37669923 PMCID: PMC10480221 DOI: 10.1038/s41392-023-01589-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 07/22/2023] [Accepted: 08/02/2023] [Indexed: 09/07/2023] Open
Abstract
Undruggable proteins are a class of proteins that are often characterized by large, complex structures or functions that are difficult to interfere with using conventional drug design strategies. Targeting such undruggable targets has been considered also a great opportunity for treatment of human diseases and has attracted substantial efforts in the field of medicine. Therefore, in this review, we focus on the recent development of drug discovery targeting "undruggable" proteins and their application in clinic. To make this review well organized, we discuss the design strategies targeting the undruggable proteins, including covalent regulation, allosteric inhibition, protein-protein/DNA interaction inhibition, targeted proteins regulation, nucleic acid-based approach, immunotherapy and others.
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Affiliation(s)
- Xin Xie
- State Key Laboratory of Southwestern Chinese Medicine Resources, College of Medical Technology and School of Pharmacy, Chengdu University of Traditional Chinese Medicine, 611137, Chengdu, China
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Tingting Yu
- State Key Laboratory of Southwestern Chinese Medicine Resources, College of Medical Technology and School of Pharmacy, Chengdu University of Traditional Chinese Medicine, 611137, Chengdu, China
| | - Xiang Li
- State Key Laboratory of Southwestern Chinese Medicine Resources, College of Medical Technology and School of Pharmacy, Chengdu University of Traditional Chinese Medicine, 611137, Chengdu, China
| | - Nan Zhang
- State Key Laboratory of Southwestern Chinese Medicine Resources, College of Medical Technology and School of Pharmacy, Chengdu University of Traditional Chinese Medicine, 611137, Chengdu, China
- Department of Dermatology and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, 610041, Chengdu, China
| | - Leonard J Foster
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Cheng Peng
- State Key Laboratory of Southwestern Chinese Medicine Resources, College of Medical Technology and School of Pharmacy, Chengdu University of Traditional Chinese Medicine, 611137, Chengdu, China.
| | - Wei Huang
- State Key Laboratory of Southwestern Chinese Medicine Resources, College of Medical Technology and School of Pharmacy, Chengdu University of Traditional Chinese Medicine, 611137, Chengdu, China.
| | - Gu He
- Department of Dermatology and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, 610041, Chengdu, China.
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Summerfield SG, Yates JWT, Fairman DA. Free Drug Theory - No Longer Just a Hypothesis? Pharm Res 2022; 39:213-222. [PMID: 35112229 DOI: 10.1007/s11095-022-03172-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/19/2022] [Indexed: 12/14/2022]
Abstract
The Free Drug Hypothesis is a well-established concept within the scientific lexicon pervading many areas of Drug Discovery and Development, and yet it is poorly defined by virtue of many variations appearing in the literature. Clearly, unbound drug is in dynamic equilibrium with respect to absorption, distribution, metabolism, elimination, and indeed, interaction with the desired pharmacological target. Binding interactions be they specific (e.g. high affinity) or nonspecific (e.g. lower affinity/higher capacity) are governed by the same fundamental physicochemical tenets including Hill-Langmuir Isotherms, the Law of Mass Action and Drug Receptor Theory. With this in mind, it is time to recognise a more coherent version and consider it the Free Drug Theory and a hypothesis no longer. Today, we have the experimental and modelling capabilities, pharmacological knowledge, and an improved understanding of unbound drug distribution (e.g. Kpuu) to raise the bar on our understanding and analysis of experimental data. The burden of proof should be to rule out mechanistic possibilities and/or experimental error before jumping to the conclusion that any observations contradict these fundamentals.
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Affiliation(s)
- Scott G Summerfield
- UK Bioanalysis Immunogenicity and Biomarkers, GSK R&D, Stevenage, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK.
| | - James W T Yates
- Drug Metabolism and Pharmacokinetics, GSK R&D, Stevenage, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
| | - David A Fairman
- Clinical Pharmacology Modelling and Simulation, GSK R&D, Stevenage, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
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Song Z, Wang M, Ge Y, Chen XP, Xu Z, Sun Y, Xiong XF. Tyrosine phosphatase SHP2 inhibitors in tumor-targeted therapies. Acta Pharm Sin B 2021; 11:13-29. [PMID: 33532178 PMCID: PMC7838030 DOI: 10.1016/j.apsb.2020.07.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/10/2020] [Accepted: 07/15/2020] [Indexed: 12/22/2022] Open
Abstract
Src homology containing protein tyrosine phosphatase 2 (SHP2) represents a noteworthy target for various diseases, serving as a well-known oncogenic phosphatase in cancers. As a result of the low cell permeability and poor bioavailability, the traditional inhibitors targeting the protein tyrosine phosphate catalytic sites are generally suffered from unsatisfactory applied efficacy. Recently, a particularly large number of allosteric inhibitors with striking inhibitory potency on SHP2 have been identified. In particular, few clinical trials conducted have made significant progress on solid tumors by using SHP2 allosteric inhibitors. This review summarizes the development and structure–activity relationship studies of the small-molecule SHP2 inhibitors for tumor therapies, with the purpose of assisting the future development of SHP2 inhibitors with improved selectivity, higher oral bioavailability and better physicochemical properties.
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Key Words
- ALK, anaplastic lymphoma kinase
- AML, acute myeloid leukemia
- Allosteric inhibitor
- B-ALL, B-cell acute lymphoblastic leukemia
- BTLA, B and T lymphocyte attenuator
- CADD, computer aided drug design
- CSF-1, colony stimulating factor-1
- CTLA-4, cytotoxic T lymphocyte-associated antigen-4
- EGFR, epidermal growth factor receptor
- ERK1/2, extracelluar signal-regulated kinase 1/2
- FLT3, Fms-like tyrosine kinase-3
- GAB2, Grb2-associated binding protein-2
- GRB2, growth factor receptor-bound protein 2
- HER2, human epidermal growth factor receptor-2
- HGF/SF, hepatocyte growth factor/scatter factor
- JAK, Janus kinase
- KRAS, v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog
- MAPK, mitogen-activated protein kinase
- NLRP3, NLR family, pyrin domain containing protein 3
- PD-1/PDL-1, programmed cell death protein-1/programmed death ligand-1
- PDAC, pancreatic ductal adenocarcinoma
- PDX, patient-derived xenograft
- PI3K, phosphatidylinositol 3 kinase
- PTK, protein tyrosine kinase
- PTP, protein tyrosine phosphatase
- Phosphatase
- RAS, rat sarcoma protein
- RTKs, receptor tyrosine kinase inhibitors
- SAR, structure–activity relationship
- SBDD, structure-based drug design
- SCC, squamous cell carcinoma
- SCNA, somatic copy number change
- SHP2
- SHP2, Src homology containing protein tyrosine phosphatase 2
- STAT, signal transducers and activators of transcription
- Selectivity
- TIGIT, T-cell immunoglobulin and ITIM domain protein
- TKIs, tyrosine kinase inhibitors
- Tumor therapy
- hERG, human ether-a-go-go-related gene
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Affiliation(s)
- Zhendong Song
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Meijing Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, China
| | - Yang Ge
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Xue-Ping Chen
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Ziyang Xu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, China
| | - Yang Sun
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, China
| | - Xiao-Feng Xiong
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
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Rybalko N, Popelář J, Šuta D, Svobodová Burianová J, Alvaro GS, Large CH, Syka J. Effect of Kv3 channel modulators on auditory temporal resolution in aged Fischer 344 rats. Hear Res 2020; 401:108139. [PMID: 33348192 DOI: 10.1016/j.heares.2020.108139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/03/2020] [Accepted: 11/24/2020] [Indexed: 01/19/2023]
Abstract
AUT00063 and AUT00202 are novel pharmaceutical modulators of the Kv3 subfamily of voltage-gated K+ channels. Kv3.1 channels, which control fast firing of many central auditory neurons, have been shown to decline with age and this may contribute to age-related deficits in central auditory processing. In the present study, the effects of the two novel compounds that specifically modulate Kv3 channels on auditory temporal processing were examined in aged (19-25-month-old) and young-adult (3-5 month-old) Fischer 344 rats (F344) using a behavioral gap-prepulse inhibition (gap-PPI) paradigm. The acoustic startle response (ASR) and its inhibition induced by a gap in noise were measured before and after drug administration. Hearing thresholds in tested rats were evaluated by the auditory brainstem response (ABR). Aged F344 rats had significantly higher ABR thresholds, lower amplitudes of ASR, and weaker gap-PPI compared with young-adult rats. No influence of AUT00063 and AUT00202 administration was observed on ABR hearing thresholds in rats of both age groups. AUT00063 and AUT00202 had suppressive effect on ASR of F344 rats that was more pronounced with AUT00063. The degree of suppression depended on the dose and age of the rats. Both compounds significantly improved the gap-PPI performance in gap detection tests in aged rats. These results indicate that AUT00063 and AUT00202 may influence intrinsic firing properties of neurons in the central auditory system of aged animals and have the potential to treat aged-related hearing disorders.
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Affiliation(s)
- Natalia Rybalko
- Department of Auditory Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic.
| | - Jiří Popelář
- Department of Auditory Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic
| | - Daniel Šuta
- Department of Auditory Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic; Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Jana Svobodová Burianová
- Department of Auditory Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic
| | - Giuseppe S Alvaro
- Autifony Therapeutics Limited, Stevenage Bioscience Catalyst, Stevenage, UK
| | - Charles H Large
- Autifony Therapeutics Limited, Stevenage Bioscience Catalyst, Stevenage, UK
| | - Josef Syka
- Department of Auditory Neuroscience, Institute of Experimental Medicine, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4, Czech Republic
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7
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Fluyau D, Revadigar N, Manobianco BE. Challenges of the pharmacological management of benzodiazepine withdrawal, dependence, and discontinuation. Ther Adv Psychopharmacol 2018; 8:147-168. [PMID: 29713452 PMCID: PMC5896864 DOI: 10.1177/2045125317753340] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 11/23/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Benzodiazepines (BZDs) are among the most prescribed sedative hypnotics and among the most misused and abused medications by patients, in parallel with opioids. It is estimated that more than 100 million Benzodiazepine (BZD) prescriptions were written in the United States in 2009. While medically useful, BZDs are potentially dangerous. The co-occurring abuse of opioids and BZD, as well as increases in BZD abuse, tolerance, dependence, and short- and long-term side effects, have prompted a worldwide discussion about the challenging aspects of medically managing the discontinuation of BZDs. Abrupt cessation can cause death. This paper addresses the challenges of medications suggested for the management of BZD discontinuation, their efficacy, the risks of abuse and associated medical complications. The focus of this review is on the challenges of several medications suggested for the management of BZD discontinuation, their efficacy, the risks of abuse, and associated medical complications. METHODS An electronic search was performed of Medline, Worldwide Science, Directory of Open Access Journals, Embase, Cochrane Library, Google Scholar, PubMed Central, and PubMed from 1990 to 2017. The review includes double-blind, placebo-controlled studies for the most part, open-label pilot studies, and animal studies, in addition to observational research. We expand the search to review articles, naturalistic studies, and to a lesser extent, letters to the editor/case reports. We exclude abstract and poster presentations, books, and book chapters. RESULTS The efficacy of these medications is not robust. While some of these medicines are relatively safe to use, some of them have a narrow therapeutic index, with severe, life-threatening side effects. Randomized studies have been limited. There is a paucity of comparative research. The review has several limitations. The quality of the documents varies according to whether they are randomized studies, nonrandomized studies, naturalistic studies, pilot studies, letters to the editors, or case reports. CONCLUSIONS The use of medications for the discontinuation of BZDs seems appropriate. It is a challenge that requires further investigation through randomized clinical trials to maximize efficacy and to minimize additional risks and side effects.
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Affiliation(s)
- Dimy Fluyau
- Emory University School of Medicine, 1648 Pierce Dr NE, Atlanta, GA 30307, USA
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8
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Liu H, Dong K, Zhang W, Summerfield SG, Terstappen GC. Prediction of brain:blood unbound concentration ratios in CNS drug discovery employing in silico and in vitro model systems. Drug Discov Today 2018; 23:1357-1372. [PMID: 29548981 DOI: 10.1016/j.drudis.2018.03.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/03/2018] [Accepted: 03/08/2018] [Indexed: 12/15/2022]
Abstract
Recent years have seen a paradigm shift away from optimizing the brain:blood concentration ratio toward the more relevant brain:blood unbound concentration ratio (Kp,uu,br) in CNS drug discovery. Here, we review the recent developments in the in silico and in vitro model systems to predict the Kp,uu,br of discovery compounds with special emphasis on the in-vitro-in-vivo correlation. We also discuss clinical 'translation' of rodent Kp,uu,br and highlight the future directions for improvement in brain penetration prediction. Important in this regard are in silico Kp,uu,br models built on larger datasets of high quality, calibration and deeper understanding of experimental in vitro transporter systems, and better understanding of blood-brain barrier transporters and their in vivo relevance aside from P-gp and BCRP.
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Affiliation(s)
- Houfu Liu
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China.
| | - Kelly Dong
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China
| | - Wandong Zhang
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China
| | - Scott G Summerfield
- Bioanalysis, Immunogenicity and Biomarker, Platform Technology and Science, GlaxoSmithKline, Ware, UK
| | - Georg C Terstappen
- Platform Technology and Science, GlaxoSmithKline R&D Center, Shanghai, China
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Morari M, Brugnoli A, Pisanò CA, Novello S, Caccia C, Melloni E, Padoani G, Vailati S, Sardina M. Safinamide Differentially Modulates In Vivo Glutamate and GABA Release in the Rat Hippocampus and Basal Ganglia. J Pharmacol Exp Ther 2017; 364:198-206. [DOI: 10.1124/jpet.117.245100] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 11/15/2017] [Indexed: 12/13/2022] Open
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10
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Prasad Tripathi RK, Ayyannan SR. Anticonvulsant activity, organotypic hippocampal neuroprotection assay and in-silico sodium channel blocking potential of 2-amino-6-nitrobenzothiazole derived semicarbazones. Biomed Pharmacother 2017; 95:1451-1460. [PMID: 28946193 DOI: 10.1016/j.biopha.2017.09.070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 08/29/2017] [Accepted: 09/13/2017] [Indexed: 10/18/2022] Open
Abstract
Epilepsy is one of the dreadful neurodegenerative disorder characterized by recurrent, unprovoked seizures. Currently available antiepileptic drugs are still associated with enormous side effects resulting in search of newer, more effective and safer agents. In view of this, we have investigated anticonvulsant activity of 2-amino-6-nitrobenzothiazole derived semicarbazones (7-32) in various in-vivo animal seizure models viz. maximal electroshock (MES), subcutaneous pentylenetetrazole (scPTZ) and 6Hz psychomotor seizure model. Neurotoxicity was estimated by rotarod test. The compounds were also assessed for their neuroprotective potential from excitotoxic insult using organotypic hippocampal slice culture neuroprotection assay. Several compounds exhibited excellent anticonvulsant activity in MES and scPTZ models compared to reference drugs, phenytoin and levetiracetam. The results of kainic acid (KA) - induced neuroprotection assay indicated that compounds 26 and 24 were found to be most potent with IC50 of 99.54±1.27 and 101.00±1.20μM respectively. Both the compounds attenuated KA-mediated cell death in organotypic hippocampal slice cultures. Some of the compounds were found to be good antidepressants, better than the reference drug citalopram, when analyzed in forced swim test. Since semicarbazones exhibited profile resembling phenytoin, an attempt was made to screen them against human neuronal sodium channel isoform (hNav1.2) by performing computational molecular docking using AutoDock 4.2. Compound 30, 1-(5-Chloro-2-oxoindolin-3-ylidene)-4-(6-nitrobenzothiazol-2-yl)semicarbazide emerged as lead candidate possessing excellent in-vivo MES activity and high binding affinity computationally, better than the reference drug phenytoin and also exhibited neuroprotection from excitotoxic insult in KA-induced neuroprotection assay (IC50=126.80±1.24μM). However, some of the active compounds were neurotoxic at their anticonvulsant doses. Further optimization studies are needed to reduce toxicity and develop them as novel therapeutic agents for epilepsy.
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Affiliation(s)
- Rati Kailash Prasad Tripathi
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi - 221005, Uttar Pradesh, India.
| | - Senthil Raja Ayyannan
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi - 221005, Uttar Pradesh, India.
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11
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Garcia Fortanet J, Chen CHT, Chen YNP, Chen Z, Deng Z, Firestone B, Fekkes P, Fodor M, Fortin PD, Fridrich C, Grunenfelder D, Ho S, Kang ZB, Karki R, Kato M, Keen N, LaBonte LR, Larrow J, Lenoir F, Liu G, Liu S, Lombardo F, Majumdar D, Meyer MJ, Palermo M, Perez L, Pu M, Ramsey T, Sellers WR, Shultz MD, Stams T, Towler C, Wang P, Williams SL, Zhang JH, LaMarche MJ. Allosteric Inhibition of SHP2: Identification of a Potent, Selective, and Orally Efficacious Phosphatase Inhibitor. J Med Chem 2016; 59:7773-82. [DOI: 10.1021/acs.jmedchem.6b00680] [Citation(s) in RCA: 168] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Jorge Garcia Fortanet
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Christine Hiu-Tung Chen
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Ying-Nan P. Chen
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Zhouliang Chen
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Zhan Deng
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Brant Firestone
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Peter Fekkes
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Michelle Fodor
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Pascal D. Fortin
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Cary Fridrich
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Denise Grunenfelder
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Samuel Ho
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Zhao B. Kang
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Rajesh Karki
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Mitsunori Kato
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Nick Keen
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Laura R. LaBonte
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Jay Larrow
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Francois Lenoir
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Gang Liu
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Shumei Liu
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Franco Lombardo
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Dyuti Majumdar
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Matthew J. Meyer
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Mark Palermo
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Lawrence Perez
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Minying Pu
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Timothy Ramsey
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - William R. Sellers
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Michael D. Shultz
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Travis Stams
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Christopher Towler
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Ping Wang
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Sarah L. Williams
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Ji-Hu Zhang
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Matthew J. LaMarche
- Global Discovery Chemistry, ‡Oncology Disease
Area, §Center
for Proteomic Chemistry, ∥Metabolism and Pharmacokinetics, Novartis Institutes
for Biomedical Research, and ⊥Chemical and Pharmaceutical Profiling, Novartis Pharmaceuticals, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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12
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Summerfield SG, Zhang Y, Liu H. Examining the Uptake of Central Nervous System Drugs and Candidates across the Blood-Brain Barrier. ACTA ACUST UNITED AC 2016; 358:294-305. [DOI: 10.1124/jpet.116.232447] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 05/17/2016] [Indexed: 01/13/2023]
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13
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Deuis JR, Wingerd JS, Winter Z, Durek T, Dekan Z, Sousa SR, Zimmermann K, Hoffmann T, Weidner C, Nassar MA, Alewood PF, Lewis RJ, Vetter I. Analgesic Effects of GpTx-1, PF-04856264 and CNV1014802 in a Mouse Model of NaV1.7-Mediated Pain. Toxins (Basel) 2016; 8:toxins8030078. [PMID: 26999206 PMCID: PMC4810223 DOI: 10.3390/toxins8030078] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/08/2016] [Accepted: 03/10/2016] [Indexed: 12/19/2022] Open
Abstract
Loss-of-function mutations of Na(V)1.7 lead to congenital insensitivity to pain, a rare condition resulting in individuals who are otherwise normal except for the inability to sense pain, making pharmacological inhibition of Na(V)1.7 a promising therapeutic strategy for the treatment of pain. We characterized a novel mouse model of Na(V)1.7-mediated pain based on intraplantar injection of the scorpion toxin OD1, which is suitable for rapid in vivo profiling of Na(V)1.7 inhibitors. Intraplantar injection of OD1 caused spontaneous pain behaviors, which were reversed by co-injection with Na(V)1.7 inhibitors and significantly reduced in Na(V)1.7(-/-) mice. To validate the use of the model for profiling Na(V)1.7 inhibitors, we determined the Na(V) selectivity and tested the efficacy of the reported Na(V)1.7 inhibitors GpTx-1, PF-04856264 and CNV1014802 (raxatrigine). GpTx-1 selectively inhibited Na(V)1.7 and was effective when co-administered with OD1, but lacked efficacy when delivered systemically. PF-04856264 state-dependently and selectively inhibited Na(V)1.7 and significantly reduced OD1-induced spontaneous pain when delivered locally and systemically. CNV1014802 state-dependently, but non-selectively, inhibited Na(V) channels and was only effective in the OD1 model when delivered systemically. Our novel model of Na(V)1.7-mediated pain based on intraplantar injection of OD1 is thus suitable for the rapid in vivo characterization of the analgesic efficacy of Na(V)1.7 inhibitors.
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Affiliation(s)
- Jennifer R Deuis
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
- School of Pharmacy, The University of Queensland, Woolloongabba, QLD 4102, Australia.
| | - Joshua S Wingerd
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Zoltan Winter
- Department of Physiology and Pathophysiology and Department of Anaesthesiology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany.
| | - Thomas Durek
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Zoltan Dekan
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Silmara R Sousa
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Katharina Zimmermann
- Department of Physiology and Pathophysiology and Department of Anaesthesiology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany.
| | - Tali Hoffmann
- Department of Physiology and Pathophysiology and Department of Anaesthesiology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany.
| | - Christian Weidner
- Department of Physiology and Pathophysiology and Department of Anaesthesiology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany.
| | - Mohammed A Nassar
- Department of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK.
| | - Paul F Alewood
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Richard J Lewis
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Irina Vetter
- Centre for Pain Research, Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
- School of Pharmacy, The University of Queensland, Woolloongabba, QLD 4102, Australia.
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14
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Docking studies and pharmacological evaluation of antiepileptic activity of phytoconstituents. Med Chem Res 2015. [DOI: 10.1007/s00044-015-1377-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Rosato-Siri MD, Zambello E, Mutinelli C, Garbati N, Benedetti R, Aldegheri L, Graziani F, Virginio C, Alvaro G, Large CH. A Novel Modulator of Kv3 Potassium Channels Regulates the Firing of Parvalbumin-Positive Cortical Interneurons. J Pharmacol Exp Ther 2015; 354:251-60. [DOI: 10.1124/jpet.115.225748] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 06/16/2015] [Indexed: 12/19/2022] Open
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16
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Monoterpenoid terpinen-4-ol exhibits anticonvulsant activity in behavioural and electrophysiological studies. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:703848. [PMID: 25180069 PMCID: PMC4142302 DOI: 10.1155/2014/703848] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/08/2014] [Accepted: 07/08/2014] [Indexed: 11/18/2022]
Abstract
Terpinen-4-ol (4TRP) is a monoterpenoid alcoholic component of essential oils obtained from several aromatic plants. We investigated the psychopharmacological and electrophysiological activities of 4TRP in male Swiss mice and Wistar rats. 4TRP was administered intraperitoneally (i.p.) at doses of 25 to 200 mg/kg and intracerebroventricularly (i.c.v.) at concentrations of 10, 20, and 40 ng/2 μL. For in vitro experiments, 4TRP concentrations were 0.1 mM and 1.0 mM. 4TRP (i.p.) inhibited pentylenetetrazol- (PTZ-) induced seizures, indicating anticonvulsant effects. Electroencephalographic recordings showed that 4TRP (i.c.v.) protected against PTZ-induced seizures, corroborating the behavioural results. To determine whether 4TRP exerts anticonvulsant effects via regulation of GABAergic neurotransmission, we measured convulsions induced by 3-mercapto-propionic acid (3-MP). The obtained results showed involvement of the GABAergic system in the anticonvulsant action exerted by 4TRP, but flumazenil, a selective antagonist of the benzodiazepine site of the GABAA receptor, did not reverse the anticonvulsant effect, demonstrating that 4TRP does not bind to the benzodiazepine-binding site. Furthermore, 4TRP decreased the sodium current through voltage-dependent sodium channels, and thus its anticonvulsant effect may be related to changes in neuronal excitability because of modulation of these channels.
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17
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18
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Waszkielewicz AM, Gunia A, Szkaradek N, Słoczyńska K, Krupińska S, Marona H. Ion channels as drug targets in central nervous system disorders. Curr Med Chem 2013; 20:1241-85. [PMID: 23409712 PMCID: PMC3706965 DOI: 10.2174/0929867311320100005] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 01/14/2013] [Accepted: 01/18/2013] [Indexed: 12/27/2022]
Abstract
Ion channel targeted drugs have always been related with either the central nervous system (CNS), the peripheral nervous system, or the cardiovascular system. Within the CNS, basic indications of drugs are: sleep disorders, anxiety, epilepsy, pain, etc. However, traditional channel blockers have multiple adverse events, mainly due to low specificity of mechanism of action. Lately, novel ion channel subtypes have been discovered, which gives premises to drug discovery process led towards specific channel subtypes. An example is Na(+) channels, whose subtypes 1.3 and 1.7-1.9 are responsible for pain, and 1.1 and 1.2 - for epilepsy. Moreover, new drug candidates have been recognized. This review is focusing on ion channels subtypes, which play a significant role in current drug discovery and development process. The knowledge on channel subtypes has developed rapidly, giving new nomenclatures of ion channels. For example, Ca(2+)s channels are not any more divided to T, L, N, P/Q, and R, but they are described as Ca(v)1.1-Ca(v)3.3, with even newer nomenclature α1A-α1I and α1S. Moreover, new channels such as P2X1-P2X7, as well as TRPA1-TRPV1 have been discovered, giving premises for new types of analgesic drugs.
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Affiliation(s)
- A M Waszkielewicz
- Department of Bioorganic Chemistry, Chair of Organic Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Krakow, Poland.
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19
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Bohnert T, Gan LS. Plasma protein binding: from discovery to development. J Pharm Sci 2013; 102:2953-94. [PMID: 23798314 DOI: 10.1002/jps.23614] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/25/2013] [Accepted: 04/25/2013] [Indexed: 12/25/2022]
Abstract
The importance of plasma protein binding (PPB) in modulating the effective drug concentration at pharmacological target sites has been the topic of significant discussion and debate amongst drug development groups over the past few decades. Free drug theory, which states that in absence of energy-dependent processes, after steady state equilibrium has been attained, free drug concentration in plasma is equal to free drug concentration at the pharmacologic target receptor(s) in tissues, has been used to explain pharmacokinetics/pharmacodynamics relationships in a large number of cases. Any sudden increase in free concentration of a drug could potentially cause toxicity and may need dose adjustment. Free drug concentration is also helpful to estimate the effective concentration of drugs that potentially can precipitate metabolism (or transporter)-related drug-drug interactions. Disease models are extensively validated in animals to progress a compound into development. Unbound drug concentration, and therefore PPB information across species is very informative in establishing safety margins and guiding selection of First in Human (FIH) dose and human efficacious dose. The scope of this review is to give an overview of reported role of PPB in several therapeutic areas, highlight cases where PPB changes are clinically relevant, and provide drug metabolism and pharmacokinetics recommendations in discovery and development settings.
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Affiliation(s)
- Tonika Bohnert
- Preclinical PK & In Vitro ADME, Biogen Idec Inc., Cambridge, Massachusetts 02142, USA.
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20
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21
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Microdialysis in CNS PKPD Research: Unraveling Unbound Concentrations. MICRODIALYSIS IN DRUG DEVELOPMENT 2013. [DOI: 10.1007/978-1-4614-4815-0_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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22
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Nardi A, Damann N, Hertrampf T, Kless A. Advances in targeting voltage-gated sodium channels with small molecules. ChemMedChem 2012; 7:1712-40. [PMID: 22945552 DOI: 10.1002/cmdc.201200298] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 07/30/2012] [Indexed: 12/19/2022]
Abstract
Blockade of voltage-gated sodium channels (VGSCs) has been used successfully in the clinic to enable control of pathological firing patterns that occur in conditions as diverse as chronic pain, epilepsy, and arrhythmias. Herein we review the state of the art in marketed sodium channel inhibitors, including a brief compendium of their binding sites and of the cellular and molecular biology of sodium channels. Despite the preferential action of this drug class toward over-excited cells, which significantly limits potential undesired side effects on other cells, the need to develop a second generation of sodium channel inhibitors to overcome their critical clinical shortcomings is apparent. Current approaches in drug discovery to deliver novel and truly innovative sodium channel inhibitors is next presented by surveying the most recent medicinal chemistry breakthroughs in the field of small molecules and developments in automated patch-clamp platforms. Various strategies aimed at identifying small molecules that target either particular isoforms of sodium channels involved in specific diseases or anomalous sodium channel currents, irrespective of the isoform by which they have been generated, are critically discussed and revised.
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Affiliation(s)
- Antonio Nardi
- Global Drug Discovery, Department of Medicinal Chemistry, Grünenthal, Zieglerstrasse 6, 52078 Aachen, Germany.
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23
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Abstract
Ion channels are targets of many therapeutically useful agents, and worldwide sales of ion channel-targeted drugs are estimated to be approximately US$12 billion. Nevertheless, considering that over 400 genes encoding ion channel subunits have been identified, ion channels remain significantly under-exploited as therapeutic targets. This is at least partly due to limitations in high-throughput assay technologies that support screening and lead optimization. Will the recent developments in automated electrophysiology rectify this situation? What are the other major limitations and can they be overcome? In this article, we review the status of ion channel drug discovery, discuss current challenges and propose alternative approaches that may facilitate the discovery of new drugs in the future.
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Ben-Cherif W, Dridi I, Aouam K, Ben-Attia M, Reinberg A, Boughattas NA. Chronotolerance study of the antiepileptic drug valproic acid in mice. J Circadian Rhythms 2012; 10:3. [PMID: 22574933 PMCID: PMC3431278 DOI: 10.1186/1740-3391-10-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 04/14/2012] [Indexed: 11/10/2022] Open
Abstract
Background Valproic acid (VPA) is an antiepileptic drug widely used for the treatment of absence seizures and generalized tonic-clonic seizures. The present work aims to study whether VPA-induced toxicity varies according to the dosing-time in the 24 hour-scale. Methods The influence of dosing-time on tolerance to VPA was investigated in 120 male Swiss mice synchronized under a light-dark cycle (12:12). The mean VPA lethal dose was first determined to be 850 ± 0.2 mg/kg, i.p.. Such a dose was administered by i.p. route to a total of 90 mice divided in six circadian stages [1, 5, 9, 13, 17 and 21 Hours After Light Onset (HALO)] (15 mice/circadian time); 30 mice were used as control (5 mice / circadian time). Results The surviving treated mice exhibited a significant circadian variation in rectal temperature and body weight loss (p < 0.001). The least rectal temperature change and body weight loss occurred when VPA was injected at 9 HALO. Drug dosing at 9 HALO resulted in -9 % weight loss whereas drug dosing at 17 HALO was -15 % (Ø = 20.3 HALO ± 1.1 h, p ≤ 0.0001). Lethal toxicity also varied according to circadian dosing-time (χ2 = 42.1, p < 0.0001). The highest (60 %) and the lowest (6.67 %) survival rates were observed at 9 HALO and 17 HALO respectively. Cosinor analyses validated a significant circadian rhythm in survival duration with an acrophase at 8.4 HALO ± 0.75 h (p < 0.001). Conclusions With regards to these data the optimal tolerance to VPA occurred when the drug was administered in the second half of the light-rest span of mice which is physiologically analogous to the second half of the night for human patients.
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Affiliation(s)
- Wafa Ben-Cherif
- Laboratoire de Pharmacologie, Faculté de Médecine, Université de Monastir, Monastir, Tunisia.
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25
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Large CH, Sokal DM, Nehlig A, Gunthorpe MJ, Sankar R, Crean CS, VanLandingham KE, White HS. The spectrum of anticonvulsant efficacy of retigabine (ezogabine) in animal models: Implications for clinical use. Epilepsia 2012; 53:425-36. [DOI: 10.1111/j.1528-1167.2011.03364.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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26
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Bundgaard C, Sveigaard C, Brennum LT, Stensbøl TB. Associating in vitro target binding and in vivo CNS occupancy of serotonin reuptake inhibitors in rats: the role of free drug concentrations. Xenobiotica 2011; 42:256-65. [PMID: 22017605 DOI: 10.3109/00498254.2011.618953] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The present study aimed at investigating the theory that free (unbound) active site concentrations are the best predictors of target binding of compounds blocking the serotonin transporter (Sert) in the central nervous system (CNS). Thirteen serotonin reuptake inhibitors were evaluated for their Sert-binding affinities in vitro and in vivo in rats together with their unbound fractions in plasma and brain. Cortical Sert occupancy was used in vivo to acquire EC₅₀-estimates from total plasma, free plasma, whole brain, and free brain concentrations after acute drug administration. The in vitro-in vivo Sert occupancy analyses showed that the best correlation was achieved when unbound brain concentrations were employed. Unbound brain concentrations also provided a better correlation when compared with unbound plasma concentrations, which could be related to lack of equilibrium between plasma and brain at time of measurements or involvement of active brain efflux processes. In addition, brain-free fractions were shown to be directly correlated to the lipophilicity of the compounds. These data emphasize the use and impact of applying free fraction data in assessment of pharmacological in vitro-in vivo correlations and demonstrates its use to validate in vivo Sert occupancy as pharmacodynamic marker for serotonin reuptake inhibitors in rats.
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27
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Nagarajan M, Maruthanayagam V, Sundararaman M. A review of pharmacological and toxicological potentials of marine cyanobacterial metabolites. J Appl Toxicol 2011; 32:153-85. [PMID: 21910132 DOI: 10.1002/jat.1717] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 06/22/2011] [Accepted: 06/22/2011] [Indexed: 11/07/2022]
Abstract
Novel toxic metabolites from marine cyanobacteria have been thoroughly explored. Biologically active and chemically diverse compounds that could be hepatotoxic, neurotoxic or cytotoxic, such as cyclic peptides, lipopeptides, fatty acid amides, alkaloids and saccharides, have been produced from marine cyanobacteria. Many reports have revealed that biosynthesis of active metabolites is predominant during cyanobacterial bloom formation. Marine cyanobacterial toxic metabolites exhibit important biological properties, such as interfering in signal transduction either by activation or blockage of sodium channels or by targeting signaling proteins; inducing apoptosis by disrupting cytoskeletal proteins; and inhibiting membrane transporters, receptors, serine proteases and topoisomerases. The pharmacological importance of these metabolites resides in their proliferation and growth-controlling abilities towards cancer cell lines and disease-causing potent microbial agents (bacteria, virus, fungi and protozoa). Besides their toxic and pharmacological potentials, the present review discusses structural and functional resemblance of marine cyanobacterial metabolites to marine algae, sponges and mollusks.
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Affiliation(s)
- M Nagarajan
- Department of Marine Biotechnology, School of Marine Sciences, Bharathidasan University, Tiruchirappalli-620 024, Tamil Nadu, India
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Large CH, Bison S, Sartori I, Read KD, Gozzi A, Quarta D, Antolini M, Hollands E, Gill CH, Gunthorpe MJ, Idris N, Neill JC, Alvaro GS. The Efficacy of Sodium Channel Blockers to Prevent Phencyclidine-Induced Cognitive Dysfunction in the Rat: Potential for Novel Treatments for Schizophrenia. J Pharmacol Exp Ther 2011; 338:100-13. [DOI: 10.1124/jpet.110.178475] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
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Bogdanov VB, Multon S, Chauvel V, Bogdanova OV, Prodanov D, Makarchuk MY, Schoenen J. Migraine preventive drugs differentially affect cortical spreading depression in rat. Neurobiol Dis 2010; 41:430-5. [PMID: 20977938 DOI: 10.1016/j.nbd.2010.10.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/10/2010] [Accepted: 10/15/2010] [Indexed: 10/18/2022] Open
Abstract
Cortical spreading depression (CSD) is the most likely cause of the migraine aura. Drugs with distinct pharmacological properties are effective in the preventive treatment of migraine. To test the hypothesis that their common denominator might be suppression of CSD we studied in rats the effect of three drugs used in migraine prevention: lamotrigine which is selectively effective on the aura but not on the headache, valproate and riboflavin which have a non-selective effect. Rats received for 4 weeks daily intraperitoneal injections of one of the three drugs. For valproate and riboflavin we used saline as control, for lamotrigine its vehicle dimethyl sulfoxide. After treatment, cortical spreading depressions were elicited for 2h by occipital KCl application. We measured CSD frequency, its propagation between a posterior (parieto-occipital) and an anterior (frontal) electrode, and number of Fos-immunoreactive nuclei in frontal cortex. Lamotrigine suppressed CSDs by 37% and 60% at posterior and anterior electrodes. Valproate had no effect on posterior CSDs, but reduced anterior ones by 32% and slowed propagation velocity. Riboflavin had no significant effect at neither recording site. Frontal Fos expression was decreased after lamotrigine and valproate, but not after riboflavin. Serum levels of administered drugs were within the range of those usually effective in patients. Our study shows that preventive anti-migraine drugs have differential effects on CSD. Lamotrigine has a marked suppressive effect which correlates with its rather selective action on the migraine aura. Valproate and riboflavin have no effect on the triggering of CSD, although they are effective in migraine without aura. Taken together, these results are compatible with a causal role of CSD in migraine with aura, but not in migraine without aura.
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Affiliation(s)
- Volodymyr Borysovych Bogdanov
- Headache Research Unit, GIGA-Neurosciences and Department of Neurology, Liège University, CHU Sart Tilman B36, T4, +1, B-4000, Liège, Belgium
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Zuliani V, Fantini M, Nigam A, Stables JP, Patel MK, Rivara M. Anticonvulsant activity of 2,4(1H)-diarylimidazoles in mice and rats acute seizure models. Bioorg Med Chem 2010; 18:7957-65. [PMID: 20943396 DOI: 10.1016/j.bmc.2010.09.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 08/30/2010] [Accepted: 09/14/2010] [Indexed: 11/17/2022]
Abstract
2,4(1H)-Diarylimidazoles have been previously shown to inhibit hNa(V)1.2 sodium (Na) channel currents. Since many of the clinically used anticonvulsants are known to inhibit Na channels as an important mechanism of their action, these compounds were tested in two acute rodent seizure models for anticonvulsant activity (MES and scMet) and for sedative and ataxic side effects. Compounds exhibiting antiepileptic activity were further tested to establish a dose response curve (ED(50)). The experimental data identified four compounds with anticonvulsant activity in the MES acute seizure rodent model (compound 10, ED(50)=61.7mg/kg; compound 13, ED(50)=46.8mg/kg, compound 17, ED(50)=129.5mg/kg and compound 20, ED(50)=136.7mg/kg). Protective indexes (PI=TD(50)/ED(50)) ranged from 2.1 (compound 10) to greater than 3.6 (compounds 13, 17 and 20). All four compounds were shown to inhibit hNa(V)1.2 in a dose dependant manner. Even if a correlation between sodium channel inhibition and anticonvulsant activity was unclear, these studies identify four Na channel antagonists with anticonvulsant activity, providing evidence that these derivatives could be potential drug candidates for development as safe, new and effective antiepileptic drugs (AEDs).
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Affiliation(s)
- Valentina Zuliani
- Dipartimento Farmaceutico, Università degli Studi di Parma, V.le G.P. Usberti, 27/A, I-43124 Parma, Italy.
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Read KD, Braggio S. Assessing brain free fraction in early drug discovery. Expert Opin Drug Metab Toxicol 2010; 6:337-44. [PMID: 20102287 DOI: 10.1517/17425250903559873] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD The incorporation of brain tissue binding routinely in CNS drug discovery screening strategies has markedly changed the way CNS drug discovery is performed and is proving to be a valuable tool in identifying new therapies for CNS diseases. For many years emphasis has been placed on the magnitude of the brain to blood ratio, the bigger the better, even though, in many cases, brain total concentration (C(brain)) has no or, at best, poor correlation with receptor occupancy/pharmacodynamic readout. Today, C(brain) values measured during in vivo experiments are corrected for the fraction unbound measured through in vitro experiments using brain tissue homogenate or brain tissue slice to obtain an estimate of the brain unbound concentration (C(u,brain)), and this has been demonstrated across a range of CNS targets to give a much better correlation with receptor occupancy/pharmacodynamic readout. This apparently simple change in CNS lead optimisation strategy has de facto revolutionised the vision of the brain penetration concepts. AREAS COVERED IN THIS REVIEW This review will provide an overview of the use and applications of assessing brain free fraction to determine C(u,brain). TAKE HOME MESSAGE Assessing brain free fraction to determine C(u,brain) in CNS lead optimisation strategies is the surrogate of choice for rapidly assessing biophase concentration for the majority of CNS targets.
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Affiliation(s)
- Kevin D Read
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, Scotland, UK.
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Kalinichev M, Bradford A, Bison S, Lucas A, Sartori I, Garbati N, Andreetta F, Bate S, Austin NE, Jones DNC, Read KD, Alvaro G, Large CH. Potentiation of the anticonvulsant efficacy of sodium channel inhibitors by an NK1-receptor antagonist in the rat. Epilepsia 2010; 51:1543-51. [DOI: 10.1111/j.1528-1167.2009.02482.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Zona C, Pieri M, Carunchio I, Curcio L, Klitgaard H, Margineanu DG. Brivaracetam (ucb 34714) inhibits Na+ current in rat cortical neurons in culture. Epilepsy Res 2010; 88:46-54. [DOI: 10.1016/j.eplepsyres.2009.09.024] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 09/22/2009] [Accepted: 09/25/2009] [Indexed: 11/29/2022]
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Hammarlund-Udenaes M. Active-site concentrations of chemicals - are they a better predictor of effect than plasma/organ/tissue concentrations? Basic Clin Pharmacol Toxicol 2009; 106:215-20. [PMID: 20050843 DOI: 10.1111/j.1742-7843.2009.00517.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Active-site concentrations can be defined as the concentrations of unbound, pharmacologically active substances at the site of action. In contrast, the total concentrations of the drug in plasma/organ/tissue also include the protein- or tissue-bound molecules that are pharmacologically inactive. Plasma and whole tissue concentrations are used as predictors of effects and side effects because of their ease of sampling, while the concentrations of unbound drug in tissue are more difficult to measure. However, with the introduction of microdialysis and subsequently developed techniques, it has become possible to test the free drug hypothesis. The brain is an interesting organ in this regard because of the presence of the blood-brain barrier with its tight junctions and active efflux and influx transporters. We have proposed that research into brain drug delivery be divided into three main areas: the rate of delivery (PS, CL(in)), the extent of delivery (K(p,uu)) and the non-specific affinity of the drug to brain tissue, described by the volume of distribution of unbound drug in the brain (V(u,brain)). In this way, the concentration of unbound drug at the target site can be estimated from the total brain concentration and the plasma concentration after measuring the fraction of unbound drug. Results so far fully support the theory that active site concentrations are the best predictors when active transport is present. However, there is an urgent need to collect more relevant data for predicting active site concentrations in tissues with active transporters in their plasma membranes.
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Affiliation(s)
- Margareta Hammarlund-Udenaes
- Division of Pharmacokinetics and Drug Therapy, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden.
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Nalivaeva NN, Belyaev ND, Turner AJ. Sodium valproate: an old drug with new roles. Trends Pharmacol Sci 2009; 30:509-14. [PMID: 19762089 DOI: 10.1016/j.tips.2009.07.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 07/19/2009] [Accepted: 07/21/2009] [Indexed: 01/16/2023]
Abstract
Sodium valproate, or Epilim, has been widely used as a broad spectrum, anticonvulsant drug for over 40 years and exhibits a good safety profile. Some of the actions of valproate arise from its more recently described histone deacetylase (HDAC) inhibitory properties and hence it can specifically modulate gene expression. There is now accumulating evidence that HDAC inhibitors may have potential in the treatment of CNS disorders and, in this context, valproate has much potential as a brain-penetrant, clinically available and well tested drug. This article reviews the pharmacology of this remarkable molecule, focusing on its actions as a neuroprotectant and hence with new potential in the treatment of neurodegenerative diseases.
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Affiliation(s)
- Natalia N Nalivaeva
- Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
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