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Wang L, Zellmer SG, Printzenhoff DM, Castle NA. Addition of a single methyl group to a small molecule sodium channel inhibitor introduces a new mode of gating modulation. Br J Pharmacol 2015. [PMID: 26220736 DOI: 10.1111/bph.13259] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Aryl sulfonamide Nav 1.3 or Nav 1.7 voltage-gated sodium (Nav ) channel inhibitors interact with the Domain 4 voltage sensor domain (D4 VSD). During studies to better understand the structure-activity relationship of this interaction, an additional mode of channel modulation, specifically slowing of inactivation, was revealed by addition of a single methyl moiety. The objective of the current study was to determine if these different modulatory effects are mediated by the same or distinct interactions with the channel. EXPERIMENTAL APPROACH Electrophysiology and site-directed mutation were used to compare the effects of PF-06526290 and its desmethyl analogue PF-05661014 on Nav channel function. KEY RESULTS PF-05661014 selectively inhibits Nav 1.3 versus Nav 1.7 currents by stabilizing inactivated channels via interaction with D4 VSD. In contrast, PF-06526290, which differs from PF-05661014 by a single methyl group, exhibits a dual effect. It greatly slows inactivation of Nav channels in a subtype-independent manner. However, upon prolonged depolarization to induce inactivation, PF-06526290 becomes a Nav subtype selective inhibitor similar to PF-05661014. Mutation of the D4 VSD modulates inhibition of Nav 1.3 or Nav 1.7 by both PF-05661014 and PF-06526290, but has no effect on the inactivation slowing produced by PF-06526290. This finding, along with the absence of functional inhibition of PF-06526290-induced inactivation slowing by PF-05661014, suggests that distinct interactions underlie the two modes of Nav channel modulation. CONCLUSIONS AND IMPLICATIONS Addition of a methyl group to a Nav channel inhibitor introduces an additional mode of gating modulation, implying that a single compound can affect sodium channel function in multiple ways.
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202
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Duan G, Guo S, Zhang Y, Ying Y, Huang P, Wang Q, Zhang L, Zhang X. The Effect of SCN9A Variation on Basal Pain Sensitivity in the General Population: An Experimental Study in Young Women. THE JOURNAL OF PAIN 2015; 16:971-80. [DOI: 10.1016/j.jpain.2015.06.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 06/09/2015] [Accepted: 06/24/2015] [Indexed: 10/23/2022]
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203
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Tang Z, Chen Z, Tang B, Jiang H. Primary erythromelalgia: a review. Orphanet J Rare Dis 2015; 10:127. [PMID: 26419464 PMCID: PMC4589109 DOI: 10.1186/s13023-015-0347-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/24/2015] [Indexed: 12/19/2022] Open
Abstract
Primary erythromelalgia (PE ORPHA90026) is a rare autosomal dominant neuropathy characterized by the combination of recurrent burning pain, warmth and redness of the extremities. The incidence rate of PE ranges from 0.36 to 1.1 per 100,000 persons. Gender ratio differs according to different studies and no evidence showed a gender preference. Clinical onset of PE is often in the first decade of life. Burning pain is the most predominant symptom and is usually caused and precipitated by warmth and physical activities. Reported cases of PE contain both inherited and sporadic forms. Genetic etiology of PE is mutations on SCN9A, the encoding gene of a voltage-gated sodium channel subtype Nav1.7. Diagnosis of PE is made upon clinical manifestations and screening for mutations on SCN9A. Exclusion of several other treatable diseases/secondary erythromelalgia is also necessary because of the lack of biomarkers specifically for PE. Differential diagnoses can include Fabry disease, cellulites, Raynaud phenomenon, vasculitis and so on. Diagnostic methods often involve complete blood count, imaging studies and thermograph. Treatment for PE is unsatisfactory and highly individualized. Frequently used pain relieving drugs involve sodium channel blockers such as lidocaine, carbamazepine and mexiletine. Novel drugs such as PF-05089771 and TV-45070 could be promising in ameliorating pain symptoms due to their Nav1.7 selectivity. Patients’ symptoms often worsen over time and many patients develop ulcerations and gangrenes caused by excessive exposure to low temperature in order to relieve pain. This review mainly focuses on PE and the causative gene SCN9A -- its mutations and their effects on Nav1.7 channels’ electrophysiological properties. We propose a genotype-channelopathy-phenotype correlation network underlying PE etiology which could provide guidance for future therapeutics.
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Affiliation(s)
- Zhaoli Tang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China.
| | - Zhao Chen
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China.
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,State Key Lab of Medical Genetics, Central South University, 110 Xiangya road, Changsha, 410078, Hunan, China.
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, 87 Xiangya road, Changsha, 410008, Hunan, China. .,State Key Lab of Medical Genetics, Central South University, 110 Xiangya road, Changsha, 410078, Hunan, China.
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204
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Barbosa C, Tan ZY, Wang R, Xie W, Strong JA, Patel RR, Vasko MR, Zhang JM, Cummins TR. Navβ4 regulates fast resurgent sodium currents and excitability in sensory neurons. Mol Pain 2015; 11:60. [PMID: 26408173 PMCID: PMC4582632 DOI: 10.1186/s12990-015-0063-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/10/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Increased electrical activity in peripheral sensory neurons including dorsal root ganglia (DRG) and trigeminal ganglia neurons is an important mechanism underlying pain. Voltage gated sodium channels (VGSC) contribute to the excitability of sensory neurons and are essential for the upstroke of action potentials. A unique type of VGSC current, resurgent current (INaR), generates an inward current at repolarizing voltages through an alternate mechanism of inactivation referred to as open-channel block. INaRs are proposed to enable high frequency firing and increased INaRs in sensory neurons are associated with pain pathologies. While Nav1.6 has been identified as the main carrier of fast INaR, our understanding of the mechanisms that contribute to INaR generation is limited. Specifically, the open-channel blocker in sensory neurons has not been identified. Previous studies suggest Navβ4 subunit mediates INaR in central nervous system neurons. The goal of this study was to determine whether Navβ4 regulates INaR in DRG sensory neurons. RESULTS Our immunocytochemistry studies show that Navβ4 expression is highly correlated with Nav1.6 expression predominantly in medium-large diameter rat DRG neurons. Navβ4 knockdown decreased endogenous fast INaR in medium-large diameter neurons as measured with whole-cell voltage clamp. Using a reduced expression system in DRG neurons, we isolated recombinant human Nav1.6 sodium currents in rat DRG neurons and found that overexpression of Navβ4 enhanced Nav1.6 INaR generation. By contrast neither overexpression of Navβ2 nor overexpression of a Navβ4-mutant, predicted to be an inactive form of Navβ4, enhanced Nav1.6 INaR generation. DRG neurons transfected with wild-type Navβ4 exhibited increased excitability with increases in both spontaneous activity and evoked activity. Thus, Navβ4 overexpression enhanced INaR and excitability, whereas knockdown or expression of mutant Navβ4 decreased INaR generation. CONCLUSION INaRs are associated with inherited and acquired pain disorders. However, our ability to selectively target and study this current has been hindered due to limited understanding of how it is generated in sensory neurons. This study identified Navβ4 as an important regulator of INaR and excitability in sensory neurons. As such, Navβ4 is a potential target for the manipulation of pain sensations.
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Affiliation(s)
- Cindy Barbosa
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, USA. .,Department of Pharmacology and Toxicology, Stark Neurosciences Research Institute, 320 West 25th Street, NB-414F, Indianapolis, IN, 46202-2266, USA.
| | - Zhi-Yong Tan
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, USA. .,Department of Pharmacology and Toxicology, Stark Neurosciences Research Institute, 320 West 25th Street, NB-414F, Indianapolis, IN, 46202-2266, USA.
| | - Ruizhong Wang
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, USA.
| | - Wenrui Xie
- Department of Anesthesiology, University of Cincinnati, Cincinnati, OH, USA.
| | - Judith A Strong
- Department of Anesthesiology, University of Cincinnati, Cincinnati, OH, USA.
| | - Reesha R Patel
- Medical Neuroscience Graduate Program, Indiana University School of Medicine, Indianapolis, IN, USA. .,Department of Pharmacology and Toxicology, Stark Neurosciences Research Institute, 320 West 25th Street, NB-414F, Indianapolis, IN, 46202-2266, USA.
| | - Michael R Vasko
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, USA. .,Department of Pharmacology and Toxicology, Stark Neurosciences Research Institute, 320 West 25th Street, NB-414F, Indianapolis, IN, 46202-2266, USA.
| | - Jun-Ming Zhang
- Department of Anesthesiology, University of Cincinnati, Cincinnati, OH, USA.
| | - Theodore R Cummins
- Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, USA. .,Department of Pharmacology and Toxicology, Stark Neurosciences Research Institute, 320 West 25th Street, NB-414F, Indianapolis, IN, 46202-2266, USA.
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205
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Remacle AG, Kumar S, Motamedchaboki K, Cieplak P, Hullugundi S, Dolkas J, Shubayev VI, Strongin AY. Matrix Metalloproteinase (MMP) Proteolysis of the Extracellular Loop of Voltage-gated Sodium Channels and Potential Alterations in Pain Signaling. J Biol Chem 2015; 290:22939-44. [PMID: 26283785 DOI: 10.1074/jbc.c115.671107] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Indexed: 12/19/2022] Open
Abstract
Congenital insensitivity to pain (CIP) or congenital analgesia is a rare monogenic hereditary condition. This disorder is characterized by the inability to perceive any form of pain. Nonsense mutations in Nav.1.7, the main pain signaling voltage-gated sodium channel, lead to its truncations and, consequently, to the inactivation of the channel functionality. However, a non-truncating homozygously inherited missense mutation in a Bedouin family with CIP (Nav1.7-R907Q) has also been reported. Based on our currently acquired in-depth knowledge of matrix metalloproteinase (MMP) cleavage preferences, we developed the specialized software that predicts the presence of the MMP cleavage sites in the peptide sequences. According to our in silico predictions, the peptide sequence of the exposed extracellular unstructured region linking the S5-S6 transmembrane segments in the DII domain of the human Nav1.7 sodium channel is highly sensitive to MMP-9 proteolysis. Intriguingly, the CIP R907Q mutation overlaps with the predicted MMP-9 cleavage site sequence. Using MMP-9 proteolysis of the wild-type, CIP, and control peptides followed by mass spectrometry of the digests, we demonstrated that the mutant sequence is severalfold more sensitive to MMP-9 proteolysis relative to the wild type. Because of the substantial level of sequence homology among sodium channels, our data also implicate MMP proteolysis in regulating the cell surface levels of the Nav1.7, Nav1.6, and Nav1.8 channels, but not Nav1.9. It is likely that the aberrantly accelerated MMP-9 proteolysis during neurogenesis is a biochemical rational for the functional inactivation in Nav1.7 and that the enhanced cleavage of the Nav1.7-R907Q mutant is a cause of CIP in the Bedouin family.
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Affiliation(s)
- Albert G Remacle
- From the Sanford-Burnham Medical Research Institute, La Jolla, California 92037
| | - Sonu Kumar
- From the Sanford-Burnham Medical Research Institute, La Jolla, California 92037
| | | | - Piotr Cieplak
- From the Sanford-Burnham Medical Research Institute, La Jolla, California 92037
| | - Swathi Hullugundi
- the Department of Anesthesiology, University of California San Diego, La Jolla, California 92093, and the Veterans Affairs San Diego Healthcare System, La Jolla, California 92037
| | - Jennifer Dolkas
- the Department of Anesthesiology, University of California San Diego, La Jolla, California 92093, and the Veterans Affairs San Diego Healthcare System, La Jolla, California 92037
| | - Veronica I Shubayev
- the Department of Anesthesiology, University of California San Diego, La Jolla, California 92093, and the Veterans Affairs San Diego Healthcare System, La Jolla, California 92037
| | - Alex Y Strongin
- From the Sanford-Burnham Medical Research Institute, La Jolla, California 92037,
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206
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Latremoliere A, Latini A, Andrews N, Cronin SJ, Fujita M, Gorska K, Hovius R, Romero C, Chuaiphichai S, Painter M, Miracca G, Babaniyi O, Remor AP, Duong K, Riva P, Barrett LB, Ferreirós N, Naylor A, Penninger JM, Tegeder I, Zhong J, Blagg J, Channon KM, Johnsson K, Costigan M, Woolf CJ. Reduction of Neuropathic and Inflammatory Pain through Inhibition of the Tetrahydrobiopterin Pathway. Neuron 2015; 86:1393-406. [PMID: 26087165 PMCID: PMC4485422 DOI: 10.1016/j.neuron.2015.05.033] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 04/22/2015] [Accepted: 05/13/2015] [Indexed: 12/18/2022]
Abstract
Human genetic studies have revealed an association between GTP cyclohydrolase 1 polymorphisms, which decrease tetrahydrobiopterin (BH4) levels, and reduced pain in patients. We now show that excessive BH4 is produced in mice by both axotomized sensory neurons and macrophages infiltrating damaged nerves and inflamed tissue. Constitutive BH4 overproduction in sensory neurons increases pain sensitivity, whereas blocking BH4 production only in these cells reduces nerve injury-induced hypersensitivity without affecting nociceptive pain. To minimize risk of side effects, we targeted sepiapterin reductase (SPR), whose blockade allows minimal BH4 production through the BH4 salvage pathways. Using a structure-based design, we developed a potent SPR inhibitor and show that it reduces pain hypersensitivity effectively with a concomitant decrease in BH4 levels in target tissues, acting both on sensory neurons and macrophages, with no development of tolerance or adverse effects. Finally, we demonstrate that sepiapterin accumulation is a sensitive biomarker for SPR inhibition in vivo.
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Affiliation(s)
- Alban Latremoliere
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Alexandra Latini
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; LABOX, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, Brazil
| | - Nick Andrews
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Shane J Cronin
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; Institute of Molecular Biotechnology of the Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Masahide Fujita
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Katarzyna Gorska
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Ruud Hovius
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Carla Romero
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Surawee Chuaiphichai
- Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Michio Painter
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Giulia Miracca
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Olusegun Babaniyi
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Aline Pertile Remor
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; LABOX, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, Brazil
| | - Kelly Duong
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Priscilla Riva
- Department of Anesthesia, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Lee B Barrett
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Nerea Ferreirós
- Pharmazentrum Frankfurt, Institut für Klinische Pharmakologie, Klinikum der Goethe-Universität, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany
| | - Alasdair Naylor
- The Canterbury Consulting Group, Unit 43 Canterbury Innovation Centre, University Road, Canterbury, Kent CT2 7FG, UK
| | - Josef M Penninger
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Irmgard Tegeder
- Pharmazentrum Frankfurt, Institut für Klinische Pharmakologie, Klinikum der Goethe-Universität, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany
| | - Jian Zhong
- Burke Medical Research Institute and Brain and Mind Research Institute, Weill Medical College of Cornell University, White Plains, NY 10605, USA
| | - Julian Blagg
- The Institute of Cancer Research, London SW7 3RP, UK
| | - Keith M Channon
- Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Kai Johnsson
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Michael Costigan
- Department of Anesthesia, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
| | - Clifford J Woolf
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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207
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Abstract
INTRODUCTION Conotoxins are a large family of bioactive peptides derived from cone snail venom. They target specific classes of ion channels and other membrane proteins and may have therapeutic value, primarily in the management of pain. AREAS COVERED The authors surveyed the US patent literature covering conotoxins, and their potential therapeutic applications. They describe the various subclasses of conotoxins that are the subject of current patent applications and their therapeutic indications. Limitations that may preclude broader application of these molecules are discussed and strategies for overcoming these limitations are presented. EXPERT OPINION Despite more than 25 years of intense global conotoxin research, only one molecule has successfully reached the market. Several other conotoxin-derived candidates failed in clinical trials, indicating that 'from the bench into the clinic' translation has been more difficult than originally anticipated. Nevertheless, we are optimistic that the potent activities of these molecules and the potential for improving their biopharmaceutical properties may lead to next-generation drug candidates with favorable pharmacological properties.
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Affiliation(s)
- Thomas Durek
- a The University of Queensland, Institute for Molecular Bioscience , Brisbane 4072, QLD, Australia
| | - David J Craik
- a The University of Queensland, Institute for Molecular Bioscience , Brisbane 4072, QLD, Australia
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208
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Sujaree K, Kitjaruwankul S, Boonamnaj P, Supunyabut C, Sompornpisut P. Transmembrane Helix Assembly by Max-Min Ant System Algorithm. Chem Biol Drug Des 2015; 86:1360-72. [PMID: 26058409 DOI: 10.1111/cbdd.12600] [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: 02/27/2015] [Revised: 04/27/2015] [Accepted: 05/25/2015] [Indexed: 11/29/2022]
Abstract
Because of the rapid progress in biochemical and structural studies of membrane proteins, considerable attention has been given on developing efficient computational methods for solving low-to-medium resolution structures using sparse structural data. In this study, we demonstrate a novel algorithm, max-min ant system (MMAS), designed to find an assembly of α-helical transmembrane proteins using a rigid helix arrangement guided by distance constraints. The new algorithm generates a large variety with finite number of orientations of transmembrane helix bundle and finds the solution that is matched with the provided distance constraints based on the behavior of ants to search for the shortest possible path between their nest and the food source. To demonstrate the efficiency of the novel search algorithm, MMAS is applied to determine the transmembrane packing of KcsA and MscL ion channels from a limited distance information extracted from the crystal structures, and the packing of KvAP voltage sensor domain using a set of 10 experimentally determined constraints, and the results are compared with those of two popular used stochastic methods, simulated annealing Monte Carlo method and genetic algorithm.
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Affiliation(s)
- Kanon Sujaree
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.,Graduate School of Nanoscience and Technology, Chulalongkorn University, Bangkok 10330, Thailand
| | - Sunan Kitjaruwankul
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.,Graduate School of Nanoscience and Technology, Chulalongkorn University, Bangkok 10330, Thailand
| | - Panisak Boonamnaj
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Chirayut Supunyabut
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Pornthep Sompornpisut
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
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209
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Rouwette T, Avenali L, Sondermann J, Narayanan P, Gomez-Varela D, Schmidt M. Modulation of nociceptive ion channels and receptors via protein-protein interactions: implications for pain relief. Channels (Austin) 2015; 9:175-85. [PMID: 26039491 DOI: 10.1080/19336950.2015.1051270] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In the last 2 decades biomedical research has provided great insights into the molecular signatures underlying painful conditions. However, chronic pain still imposes substantial challenges to researchers, clinicians and patients alike. Under pathological conditions, pain therapeutics often lack efficacy and exhibit only minimal safety profiles, which can be largely attributed to the targeting of molecules with key physiological functions throughout the body. In light of these difficulties, the identification of molecules and associated protein complexes specifically involved in chronic pain states is of paramount importance for designing selective interventions. Ion channels and receptors represent primary targets, as they critically shape nociceptive signaling from the periphery to the brain. Moreover, their function requires tight control, which is usually implemented by protein-protein interactions (PPIs). Indeed, manipulation of such PPIs entails the modulation of ion channel activity with widespread implications for influencing nociceptive signaling in a more specific way. In this review, we highlight recent advances in modulating ion channels and receptors via their PPI networks in the pursuit of relieving chronic pain. Moreover, we critically discuss the potential of targeting PPIs for developing novel pain therapies exhibiting higher efficacy and improved safety profiles.
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Affiliation(s)
- Tom Rouwette
- a Max Planck Institute for Experimental Medicine. Somatosensory Signaling Group ; Goettingen , Germany
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210
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Lee JH, Mitchell R, McNicol J, Shapovalova Z, Laronde S, Tanasijevic B, Milsom C, Casado F, Fiebig-Comyn A, Collins T, Singh K, Bhatia M. Single Transcription Factor Conversion of Human Blood Fate to NPCs with CNS and PNS Developmental Capacity. Cell Rep 2015; 11:1367-76. [DOI: 10.1016/j.celrep.2015.04.056] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/13/2015] [Accepted: 04/25/2015] [Indexed: 02/06/2023] Open
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211
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Chen YC, Auer-Grumbach M, Matsukawa S, Zitzelsberger M, Themistocleous AC, Strom TM, Samara C, Moore AW, Cho LTY, Young GT, Weiss C, Schabhüttl M, Stucka R, Schmid AB, Parman Y, Graul-Neumann L, Heinritz W, Passarge E, Watson RM, Hertz JM, Moog U, Baumgartner M, Valente EM, Pereira D, Restrepo CM, Katona I, Dusl M, Stendel C, Wieland T, Stafford F, Reimann F, von Au K, Finke C, Willems PJ, Nahorski MS, Shaikh SS, Carvalho OP, Nicholas AK, Karbani G, McAleer MA, Cilio MR, McHugh JC, Murphy SM, Irvine AD, Jensen UB, Windhager R, Weis J, Bergmann C, Rautenstrauss B, Baets J, De Jonghe P, Reilly MM, Kropatsch R, Kurth I, Chrast R, Michiue T, Bennett DLH, Woods CG, Senderek J. Transcriptional regulator PRDM12 is essential for human pain perception. Nat Genet 2015; 47:803-8. [PMID: 26005867 DOI: 10.1038/ng.3308] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 04/27/2015] [Indexed: 12/12/2022]
Abstract
Pain perception has evolved as a warning mechanism to alert organisms to tissue damage and dangerous environments. In humans, however, undesirable, excessive or chronic pain is a common and major societal burden for which available medical treatments are currently suboptimal. New therapeutic options have recently been derived from studies of individuals with congenital insensitivity to pain (CIP). Here we identified 10 different homozygous mutations in PRDM12 (encoding PRDI-BF1 and RIZ homology domain-containing protein 12) in subjects with CIP from 11 families. Prdm proteins are a family of epigenetic regulators that control neural specification and neurogenesis. We determined that Prdm12 is expressed in nociceptors and their progenitors and participates in the development of sensory neurons in Xenopus embryos. Moreover, CIP-associated mutants abrogate the histone-modifying potential associated with wild-type Prdm12. Prdm12 emerges as a key factor in the orchestration of sensory neurogenesis and may hold promise as a target for new pain therapeutics.
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Affiliation(s)
- Ya-Chun Chen
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | | | - Shinya Matsukawa
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | | | - Andreas C Themistocleous
- 1] Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK. [2] Brain Function Research Group, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Tim M Strom
- 1] Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany. [2] Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Chrysanthi Samara
- Department of Medical Genetics, University of Lausanne, Lausanne, Switzerland
| | - Adrian W Moore
- Disease Mechanism Research Core, RIKEN Brain Science Institute, Saitama, Japan
| | | | | | - Caecilia Weiss
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
| | - Maria Schabhüttl
- Department of Orthopaedics, Medical University Vienna, Vienna, Austria
| | - Rolf Stucka
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
| | - Annina B Schmid
- 1] Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK. [2] School of Health and Rehabilitation Sciences, The University of Queensland, St. Lucia, Australia
| | - Yesim Parman
- Department of Neurology, Istanbul University, Istanbul, Turkey
| | - Luitgard Graul-Neumann
- Ambulantes Gesundheitszentrum der Charité Campus Virchow (Humangenetik), Universitätsmedizin Berlin, Berlin, Germany
| | - Wolfram Heinritz
- 1] Praxis für Humangenetik Cottbus, Cottbus, Germany. [2] Institut für Humangenetik, Universitätsklinikum Leipzig, Leipzig, Germany
| | - Eberhard Passarge
- 1] Institut für Humangenetik, Universitätsklinikum Leipzig, Leipzig, Germany. [2] Institut für Humangenetik, Universitätsklinikum Essen, Essen, Germany
| | - Rosemarie M Watson
- Department of Dermatology, Our Lady's Children's Hospital, Dublin, Ireland
| | - Jens Michael Hertz
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | - Ute Moog
- Institute of Human Genetics, Heidelberg University, Heidelberg, Germany
| | - Manuela Baumgartner
- Neuropädiatrische Ambulanz, Krankenhaus der Barmherzigen Schwestern Linz, Linz, Austria
| | - Enza Maria Valente
- Neurogenetics Unit, Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Diego Pereira
- Departamento de Cirugía Plástica, Hospital Infantil Universitario de San José, Bogotá, Colombia
| | | | - Istvan Katona
- Institut für Neuropathologie, Uniklinik RWTH Aachen, Aachen, Germany
| | - Marina Dusl
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
| | - Claudia Stendel
- 1] Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany. [2] German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Thomas Wieland
- Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Fay Stafford
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Frank Reimann
- Department of Clinical Biochemistry, University of Cambridge, Cambridge, UK
| | - Katja von Au
- SPZ Neuropädiatrie Charité, Universitätsmedizin Berlin, Berlin, Germany
| | - Christian Finke
- CharitéCentrum für Zahn-, Mund- und Kieferheilkunde, Arbeitsbereich Kinderzahnmedizin, Universitätsmedizin Berlin, Berlin, Germany
| | | | - Michael S Nahorski
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Samiha S Shaikh
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Ofélia P Carvalho
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Adeline K Nicholas
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Gulshan Karbani
- Yorkshire Regional Genetics Service, Chapel Allerton Hospital, Leeds, UK
| | - Maeve A McAleer
- Department of Dermatology, Our Lady's Children's Hospital, Dublin, Ireland
| | - Maria Roberta Cilio
- 1] Department of Neurology, University of California San Francisco, San Francisco, California, USA. [2] Department of Neuroscience, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy
| | - John C McHugh
- Department of Neurology and Neurophysiology, Our Lady's Children's Hospital, Dublin, Ireland
| | - Sinead M Murphy
- 1] Department of Neurology, Adelaide &Meath Hospital, Dublin, Ireland. [2] Academic Unit of Neurology, Trinity College, Dublin, Ireland
| | - Alan D Irvine
- 1] Department of Dermatology, Our Lady's Children's Hospital, Dublin, Ireland. [2] Clinical Medicine, Trinity College, Dublin, Ireland
| | - Uffe Birk Jensen
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Joachim Weis
- Institut für Neuropathologie, Uniklinik RWTH Aachen, Aachen, Germany
| | - Carsten Bergmann
- 1] Center for Human Genetics, Bioscientia, Ingelheim, Germany. [2] Department of Medicine, Renal Division, Freiburg University Medical Center, Freiburg, Germany. [3] Center for Clinical Research, Freiburg University Medical Center, Freiburg, Germany
| | - Bernd Rautenstrauss
- 1] Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany. [2] Medizinisch Genetisches Zentrum, Munich, Germany
| | - Jonathan Baets
- 1] Neurogenetics Group, VIB Department of Molecular Genetics, University of Antwerp, Antwerp, Belgium. [2] Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium. [3] Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Peter De Jonghe
- 1] Neurogenetics Group, VIB Department of Molecular Genetics, University of Antwerp, Antwerp, Belgium. [2] Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium. [3] Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Mary M Reilly
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, National Hospital for Neurology, London, UK
| | - Regina Kropatsch
- Department of Human Genetics, Ruhr-University Bochum, Bochum, Germany
| | - Ingo Kurth
- Institute of Human Genetics, Jena University Hospital, Jena, Germany
| | - Roman Chrast
- 1] Institute of Human Genetics, Technische Universität München, Munich, Germany. [2] Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden. [3] Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Tatsuo Michiue
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - David L H Bennett
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - C Geoffrey Woods
- 1] Department of Medical Genetics, University of Cambridge, Cambridge, UK. [2] Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Jan Senderek
- Friedrich-Baur-Institute, Ludwig Maximilians University Munich, Munich, Germany
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212
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de Lera Ruiz M, Kraus RL. Voltage-Gated Sodium Channels: Structure, Function, Pharmacology, and Clinical Indications. J Med Chem 2015; 58:7093-118. [PMID: 25927480 DOI: 10.1021/jm501981g] [Citation(s) in RCA: 335] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The tremendous therapeutic potential of voltage-gated sodium channels (Na(v)s) has been the subject of many studies in the past and is of intense interest today. Na(v)1.7 channels in particular have received much attention recently because of strong genetic validation of their involvement in nociception. Here we summarize the current status of research in the Na(v) field and present the most relevant recent developments with respect to the molecular structure, general physiology, and pharmacology of distinct Na(v) channel subtypes. We discuss Na(v) channel ligands such as small molecules, toxins isolated from animal venoms, and the recently identified Na(v)1.7-selective antibody. Furthermore, we review eight characterized ligand binding sites on the Na(v) channel α subunit. Finally, we examine possible therapeutic applications of Na(v) ligands and provide an update on current clinical studies.
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Affiliation(s)
- Manuel de Lera Ruiz
- Merck Research Laboratories , 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
| | - Richard L Kraus
- Merck Research Laboratories , 770 Sumneytown Pike, West Point, Pennsylvania 19486, United States
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213
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Ghimire S, Kim MS. Defensive Behavior against Noxious Heat Stimuli Is Declined with Aging Due to Decreased Pain-Associated Gene Expression in Drosophila. Biomol Ther (Seoul) 2015; 23:290-5. [PMID: 25995829 PMCID: PMC4428723 DOI: 10.4062/biomolther.2014.147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/15/2015] [Accepted: 02/26/2015] [Indexed: 12/30/2022] Open
Abstract
Aging is defined as a collective process that alters organism’s functional capacity and appearance over the course of life. Apart from an increase in susceptibility to many diseases, aging affects the cellular system that is responsible for decoding painful stimuli. Yet, aging-associated molecular mechanisms of pain perception remains elusive. Using Drosophila, we showed a decrease in temperature tolerance and a reduction in high temperature thermal avoidance with aging. Locomotor activity assay demonstrated that the age-dependent changes in heat nociception did not stem from the general decline in muscular activity. However, we identified pain-related gene expression alteration with aging. We anticipate that our findings would help opening a new window onto developing the optimal pain treatment for the elderly.
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Affiliation(s)
- Saurav Ghimire
- College of Pharmacy, Inje University, Gimhae 621-749, Republic of Korea
| | - Man Su Kim
- College of Pharmacy, Inje University, Gimhae 621-749, Republic of Korea
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214
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Abstract
The rising global prevalence of diabetes mellitus is accompanied by an increasing burden of morbidity and mortality that is attributable to the complications of chronic hyperglycaemia. These complications include blindness, renal failure and cardiovascular disease. Current therapeutic options for chronic hyperglycaemia reduce, but do not eradicate, the risk of these complications. Success in defining new preventative and therapeutic strategies hinges on an improved understanding of the molecular processes involved in the development of these complications. This Review explores the role of human genetics in delivering such insights, and describes progress in characterizing the sequence variants that influence individual predisposition to diabetic kidney disease, retinopathy, neuropathy and accelerated cardiovascular disease. Numerous risk variants for microvascular complications of diabetes have been reported, but very few have shown robust replication. Furthermore, only limited evidence exists of a difference in the repertoire of risk variants influencing macrovascular disease between those with and those without diabetes. Here, we outline the challenges associated with the genetic analysis of diabetic complications and highlight ongoing efforts to deliver biological insights that can drive translational benefits.
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215
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216
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Aggarwal S, Kheirkhah A, Cavalcanti BM, Cruzat A, Colon C, Brown E, Borsook D, Prüss H, Hamrah P. Autologous Serum Tears for Treatment of Photoallodynia in Patients with Corneal Neuropathy: Efficacy and Evaluation with In Vivo Confocal Microscopy. Ocul Surf 2015; 13:250-62. [PMID: 26045233 DOI: 10.1016/j.jtos.2015.01.005] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 01/21/2015] [Accepted: 01/01/2015] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Patients suffering from corneal neuropathy may present with photoallodynia; i.e., increased light sensitivity, frequently with a normal slit-lamp examination. This study aimed to evaluate the efficacy of autologous serum tears (AST) for treatment of severe photoallodynia in corneal neuropathy and to correlate clinical findings with corneal subbasal nerve alterations by in vivo confocal microscopy (IVCM). METHODS Retrospective case control study with 16 patients with neuropathy-induced severe photoallodynia compared to 16 normal controls. Symptom severity, clinical examination and bilateral corneal IVCM scans were recorded. RESULTS All patients suffered from extreme photoallodynia (8.8±1.1) with no concurrent ocular surface disease. Subbasal nerves were significantly decreased at baseline in patients compared to controls; total nerve length (9208±1264 vs 24714±1056 μm/mm(2); P<.0001) and total nerve number (9.6±1.4 vs 28.6±2.0; P<.0001), respectively. Morphologically, significantly increased reflectivity (2.9±0.2 vs 1.8±0.1; P<.0001), beading (in 93.7%), and neuromas (in 62.5%) were seen. AST (3.6±2.1 months) resulted in significantly decreased symptom severity (1.6±1.7; P=.02). IVCM demonstrated significantly improved nerve parameters (P<.005), total nerve length (15451±1595 μm/mm(2)), number (13.9±2.1), and reflectivity (1.9±0.1). Beading and neuromas were seen in only 56.2% and 7.6% of patients. CONCLUSION Patients with corneal neuropathy-induced photoallodynia show profound alterations in corneal nerves. AST restores nerve topography through nerve regeneration, and this correlated with improvement in patient-reported photoallodynia. The data support the notion that corneal nerve damage results in alterations in afferent trigeminal pathways to produce photoallodynia.
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Affiliation(s)
- Shruti Aggarwal
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Ahmad Kheirkhah
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Bernardo M Cavalcanti
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Andrea Cruzat
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Clara Colon
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Emma Brown
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - David Borsook
- Pain/Analgesia Imaging Neuroscience (P.A.I.N.) Group, Department of Anesthesia, Boston Children's Hospital, Center for Pain and the Brain, Harvard Medical School, Waltham, MA, USA
| | - Harald Prüss
- Department of Neurology, Charité University Medicine Berlin, Germany
| | - Pedram Hamrah
- Ocular Surface Imaging Center, Cornea and Refractive Surgery Service, Massachusetts Eye & Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
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217
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Wilkinson TCI, Gardener MJ, Williams WA. Discovery of Functional Antibodies Targeting Ion Channels. ACTA ACUST UNITED AC 2014; 20:454-67. [DOI: 10.1177/1087057114560698] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Ion channels play critical roles in physiology and disease by modulation of cellular functions such as electrical excitability, secretion, cell migration, and gene transcription. Ion channels represent an important target class for drug discovery that has been largely addressed, to date, using small-molecule approaches. A significant opportunity exists to target these channels with antibodies and alternative formats of biologics. Antibodies display high specificity and affinity for their target antigen, and they have the potential to target ion channels very selectively. Nevertheless, isolating antibodies to this target class is challenging due to the difficulties in expression and purification of ion channels in a format suitable for antibody drug discovery in addition to the complexity of screening for function. In this article, we will review the current state of ion channel biologics discovery and the progress that has been made. We will also highlight the challenges in isolating functional antibodies to these targets and how these challenges may be addressed. Finally, we also illustrate successful approaches to isolating functional monoclonal antibodies targeting ion channels by way of a number of case studies drawn from recent publications.
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Affiliation(s)
| | | | - Wendy A. Williams
- Antibody Discovery and Protein Engineering, MedImmune, Cambridge, UK
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218
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Pain related channels are differentially expressed in neuronal and non-neuronal cells of glabrous skin of fabry knockout male mice. PLoS One 2014; 9:e108641. [PMID: 25337704 PMCID: PMC4206276 DOI: 10.1371/journal.pone.0108641] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/03/2014] [Indexed: 11/20/2022] Open
Abstract
Fabry disease (FD) is one of the X-linked lysosomal storage disorders caused by deficient functioning of the alpha-galactosidase A (α-GalA) enzyme. The α-GalA deficiency leads to multi-systemic clinical manifestations caused by the preferential accumulation of globotriaosylceramide in the endothelium and vascular smooth muscles. A hallmark symptom of FD patients is peripheral pain that appears in the early stage of the disease. Pain in FD patients is a peripheral small-fiber idiopathic neuropathy, with intra-epidermal fiber density and integrity being used for diagnosing FD in humans. However, the molecular correlates underlying pain sensation in FD remain elusive. Here, we have employed the α-GalA gene KO mouse as a model of FD in rodents to investigate molecular changes in their peripheral nervous system that may account for their algesic symptoms. The α-GalA null mice display neuropathic pain as evidenced by thermal hyperalgesia and mechanical allodynia, with histological analyses showing alterations in cutaneous innervation. Additionally, KO mice showed a decreased and scattered pattern of neuronal terminations consistent with the reduction in neuronal terminations in skin biopsies of patients with small fiber neuropathies. At the molecular level KO animals showed an increase in the expression of TRPV1 and Nav1.8, and a decrease in the expression of TRPM8. Notably, these alterations are observed in young animals. Taken together, our findings imply that the α-GalA KO mouse is a good model in which to study the peripheral small fiber neuropathy exhibited by FD patients, and provides molecular evidence for a hyperexcitability of small nociceptors in FD.
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