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Wilke SK, Benmore CJ, Alderman OLG, Sivaraman G, Ruehl MD, Hawthorne KL, Tamalonis A, Andersson DA, Williamson MA, Weber R. Plutonium oxide melt structure and covalency. Nat Mater 2024:10.1038/s41563-024-01883-3. [PMID: 38671164 DOI: 10.1038/s41563-024-01883-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
Advances in nuclear power reactors include the use of mixed oxide fuel, containing uranium and plutonium oxides. The high-temperature behaviour and structure of PuO2-x above 1,800 K remain largely unexplored, and these conditions must be considered for reactor design and planning for the mitigation of severe accidents. Here, we measure the atomic structure of PuO2-x through the melting transition up to 3,000 ± 50 K using X-ray scattering of aerodynamically levitated and laser-beam-heated samples, with O/Pu ranging from 1.57 to 1.76. Liquid structural models consistent with the X-ray data are developed using machine-learned interatomic potentials and density functional theory. Molten PuO1.76 contains some degree of covalent Pu-O bonding, signalled by the degeneracy of Pu 5f and O 2p orbitals. The liquid is isomorphous with molten CeO1.75, demonstrating the latter as a non-radioactive, non-toxic, structural surrogate when differences in the oxidation potentials of Pu and Ce are accounted for. These characterizations provide essential constraints for modelling pertinent to reactor safety design.
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Affiliation(s)
- Stephen K Wilke
- Materials Development, Inc., Arlington Heights, IL, USA.
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA.
| | - Chris J Benmore
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA
| | - Oliver L G Alderman
- ISIS Neutron & Muon Source, Rutherford Appleton Laboratory, Chilton, Didcot, UK
| | - Ganesh Sivaraman
- Department of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Matthew D Ruehl
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, IL, USA
| | - Krista L Hawthorne
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, IL, USA
| | | | - David A Andersson
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Mark A Williamson
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, IL, USA
| | - Richard Weber
- Materials Development, Inc., Arlington Heights, IL, USA
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA
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2
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Saleque N, Vastani N, Gentry C, Andersson DA, Israel MR, Bevan S. Topical Oxaliplatin Produces Gain- and Loss-of-Function in Multiple Classes of Sensory Afferents. J Pain 2024; 25:88-100. [PMID: 37524219 PMCID: PMC10877073 DOI: 10.1016/j.jpain.2023.07.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/03/2023] [Accepted: 07/26/2023] [Indexed: 08/02/2023]
Abstract
The platinum chemotherapeutic oxaliplatin produces dose-limiting pain, dysesthesia, and cold hypersensitivity in most patients immediately after infusion. An improved understanding of the mechanisms underlying these symptoms is urgently required to facilitate the development of symptomatic or preventative therapies. In this study, we have used skin-saphenous nerve recordings in vitro and behavioral experiments in mice to characterize the direct effects of oxaliplatin on different types of sensory afferent fibers. Our results confirmed that mice injected with oxaliplatin rapidly develop mechanical and cold hypersensitivities. We further noted profound changes to A fiber activity after the application of oxaliplatin to the receptive fields in the skin. Most oxaliplatin-treated Aδ- and rapidly adapting Aβ-units lost mechanical sensitivity, but units that retained responsiveness additionally displayed a novel, aberrant cold sensitivity. Slowly adapting Aβ-units did not display mechanical tachyphylaxis, and a subset of these fibers was sensitized to mechanical and cold stimulation after oxaliplatin treatment. C fiber afferents were less affected by acute applications of oxaliplatin, but a subset gained cold sensitivity. Taken together, our findings suggest that direct effects on peripheral A fibers play a dominant role in the development of acute oxaliplatin-induced cold hypersensitivity, numbness, and dysesthesia. PERSPECTIVE: The chemotherapeutic drug oxaliplatin rapidly gives rise to dose-limiting cold pain and dysesthesia. Here, we have used behavioral and electrophysiological studies of mice to characterize the responsible neurons. We show that oxaliplatin directly confers aberrant cold responsiveness to subsets of A-fibers while silencing other fibers of the same type.
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Affiliation(s)
- Nurjahan Saleque
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Nisha Vastani
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Clive Gentry
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - David A Andersson
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Mathilde R Israel
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, London, UK
| | - Stuart Bevan
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, London, UK
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3
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Strzelecki AC, Wang G, Hickam SM, Parker SS, Batrice R, Jackson JM, Conroy NA, Mitchell JN, Andersson DA, Monreal MJ, Boukhalfa H, Xu H. In Situ High-Temperature Raman Spectroscopy of UCl 3: A Combined Experimental and Theoretical Study. Inorg Chem 2023; 62:18724-18731. [PMID: 37917811 DOI: 10.1021/acs.inorgchem.3c03139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2023]
Abstract
Uranium trichloride (UCl3) has received growing interest for its use in uranium-fueled molten salt reactors and in the pyrochemical processing of used fuel. In this paper, we report for the first time the experimentally determined Raman spectra of UCl3, at both ambient condition and in situ high temperatures up to 871 K. The frequencies of five of the Raman-active vibrational modes (vi) of UCl3 exhibit a negative temperature derivative ((∂νi/∂T)P) with increasing temperature. This red-shift behavior is likely due to the elongation of U-Cl bonds. The average isobaric mode Grüneisen parameter (γiP = 0.91 ± 0.02) of UCl3 was determined through use of the coefficient of thermal expansion published in Vogel et al. (2021) and the (∂νi/∂T)P values determined in this study. These results are in general agreement with those calculated here by density functional theory (DFT+U). Finally, a comparison of the ambient band positions of UCl3 to those of isostructural lanthanide (La-Eu) and actinide chlorides (Am-Cf) has been made.
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Affiliation(s)
- Andrew C Strzelecki
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Gaoxue Wang
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Sarah M Hickam
- Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - S Scott Parker
- Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- Sigma Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Rami Batrice
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - J Matt Jackson
- Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Nathan A Conroy
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jeremy N Mitchell
- Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - David A Andersson
- Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Marisa J Monreal
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Hakim Boukhalfa
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Hongwu Xu
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
- School of Molecular Sciences and Center for Materials of the Universe, Arizona State University, Tempe, Arizona 85287, United States
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4
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Guo J, Woo V, Andersson DA, Hoyt N, Williamson M, Foster I, Benmore C, Jackson NE, Sivaraman G. AL4GAP: Active learning workflow for generating DFT-SCAN accurate machine-learning potentials for combinatorial molten salt mixtures. J Chem Phys 2023; 159:024802. [PMID: 37428051 DOI: 10.1063/5.0153021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 06/02/2023] [Indexed: 07/11/2023] Open
Abstract
Machine learning interatomic potentials have emerged as a powerful tool for bypassing the spatiotemporal limitations of ab initio simulations, but major challenges remain in their efficient parameterization. We present AL4GAP, an ensemble active learning software workflow for generating multicomposition Gaussian approximation potentials (GAP) for arbitrary molten salt mixtures. The workflow capabilities include: (1) setting up user-defined combinatorial chemical spaces of charge neutral mixtures of arbitrary molten mixtures spanning 11 cations (Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba and two heavy species, Nd, and Th) and 4 anions (F, Cl, Br, and I), (2) configurational sampling using low-cost empirical parameterizations, (3) active learning for down-selecting configurational samples for single point density functional theory calculations at the level of Strongly Constrained and Appropriately Normed (SCAN) exchange-correlation functional, and (4) Bayesian optimization for hyperparameter tuning of two-body and many-body GAP models. We apply the AL4GAP workflow to showcase high throughput generation of five independent GAP models for multicomposition binary-mixture melts, each of increasing complexity with respect to charge valency and electronic structure, namely: LiCl-KCl, NaCl-CaCl2, KCl-NdCl3, CaCl2-NdCl3, and KCl-ThCl4. Our results indicate that GAP models can accurately predict structure for diverse molten salt mixture with density functional theory (DFT)-SCAN accuracy, capturing the intermediate range ordering characteristic of the multivalent cationic melts.
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Affiliation(s)
- Jicheng Guo
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Vanessa Woo
- School of Electrical, Computer, Energy Engineering, Arizona State University, Tempe, Arizona 85287, USA
| | - David A Andersson
- Materials Science and Technology Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA
| | - Nathaniel Hoyt
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Mark Williamson
- Chemical and Fuel Cycle Technologies Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Ian Foster
- Data Science and Learning Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Chris Benmore
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Nicholas E Jackson
- Department of Chemistry, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Ganesh Sivaraman
- Data Science and Learning Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
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5
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Jami S, Deuis JR, Klasfauseweh T, Cheng X, Kurdyukov S, Chung F, Okorokov AL, Li S, Zhang J, Cristofori-Armstrong B, Israel MR, Ju RJ, Robinson SD, Zhao P, Ragnarsson L, Andersson Å, Tran P, Schendel V, McMahon KL, Tran HNT, Chin YKY, Zhu Y, Liu J, Crawford T, Purushothamvasan S, Habib AM, Andersson DA, Rash LD, Wood JN, Zhao J, Stehbens SJ, Mobli M, Leffler A, Jiang D, Cox JJ, Waxman SG, Dib-Hajj SD, Neely GG, Durek T, Vetter I. Pain-causing stinging nettle toxins target TMEM233 to modulate Na V1.7 function. Nat Commun 2023; 14:2442. [PMID: 37117223 PMCID: PMC10147923 DOI: 10.1038/s41467-023-37963-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 04/08/2023] [Indexed: 04/30/2023] Open
Abstract
Voltage-gated sodium (NaV) channels are critical regulators of neuronal excitability and are targeted by many toxins that directly interact with the pore-forming α subunit, typically via extracellular loops of the voltage-sensing domains, or residues forming part of the pore domain. Excelsatoxin A (ExTxA), a pain-causing knottin peptide from the Australian stinging tree Dendrocnide excelsa, is the first reported plant-derived NaV channel modulating peptide toxin. Here we show that TMEM233, a member of the dispanin family of transmembrane proteins expressed in sensory neurons, is essential for pharmacological activity of ExTxA at NaV channels, and that co-expression of TMEM233 modulates the gating properties of NaV1.7. These findings identify TMEM233 as a previously unknown NaV1.7-interacting protein, position TMEM233 and the dispanins as accessory proteins that are indispensable for toxin-mediated effects on NaV channel gating, and provide important insights into the function of NaV channels in sensory neurons.
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Affiliation(s)
- Sina Jami
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Jennifer R Deuis
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Tabea Klasfauseweh
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Xiaoyang Cheng
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Sergey Kurdyukov
- Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre, Centenary Institute, University of Sydney, Camperdown, NSW, 2006, Australia
| | - Felicity Chung
- Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre, Centenary Institute, University of Sydney, Camperdown, NSW, 2006, Australia
| | - Andrei L Okorokov
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, UK
| | - Shengnan Li
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, UK
| | - Jiangtao Zhang
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, P.R. China
| | - Ben Cristofori-Armstrong
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Mathilde R Israel
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE1 1UL, London, UK
| | - Robert J Ju
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Samuel D Robinson
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Peng Zhao
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Lotten Ragnarsson
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Åsa Andersson
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Poanna Tran
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Vanessa Schendel
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Kirsten L McMahon
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Hue N T Tran
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Yanni K-Y Chin
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Yifei Zhu
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Junyu Liu
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Theo Crawford
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
| | | | - Abdella M Habib
- College of Medicine, QU Health, Qatar University, PO Box 2713, Doha, Qatar
| | - David A Andersson
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, SE1 1UL, London, UK
| | - Lachlan D Rash
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, UK
| | - Jing Zhao
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, UK
| | - Samantha J Stehbens
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Mehdi Mobli
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Andreas Leffler
- Department of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Hannover, 30625, Germany
| | - Daohua Jiang
- Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, P.R. China
| | - James J Cox
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, UK
| | - Stephen G Waxman
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - Sulayman D Dib-Hajj
- Department of Neurology and Center for Neuroscience and Regeneration Research, Yale University School of Medicine, New Haven, CT, USA
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA
| | - G Gregory Neely
- Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre, Centenary Institute, University of Sydney, Camperdown, NSW, 2006, Australia
| | - Thomas Durek
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia.
- Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, St Lucia, QLD, 4072, Australia.
| | - Irina Vetter
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia.
- School of Pharmacy, The University of Queensland, Woolloongabba, QLD, 4102, Australia.
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6
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Paskins Z, Farmer CE, Manning F, Andersson DA, Barlow T, Bishop FL, Brown CA, Clark A, Clark EM, Dulake D, Gulati M, Le Maitre CL, Jones RK, Loughlin J, Mason DJ, McCarron M, Millar NL, Pandit H, Peat G, Richardson SM, Salt EJ, Taylor EJ, Troeberg L, Wilcox RK, Wise E, Wilkinson C, Watt FE. Research priorities to reduce the impact of musculoskeletal disorders: a priority setting exercise with the child health and nutrition research initiative method. Lancet Rheumatol 2022; 4:e635-e645. [PMID: 36275038 PMCID: PMC9584828 DOI: 10.1016/s2665-9913(22)00136-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Involving research users in setting priorities for research is essential to ensure the outcomes are patient-centred and maximise its value and impact. The Musculoskeletal Disorders Research Advisory Group Versus Arthritis led a research priority setting exercise across musculoskeletal disorders. The Child Health and Nutrition Research Initiative (CHNRI) method of setting research priorities with a range of stakeholders was used, involving four stages and two surveys, to: (1) gather research uncertainties, (2) consolidate these, (3) score uncertainties against importance and impact, and (4) analyse scoring for prioritisation. 213 people responded to the first survey and 285 people to the second, representing clinicians, researchers, and people with musculoskeletal disorders. Key priorities included developing and testing new treatments, better treatment targeting, early diagnosis, prevention, and better understanding and management of pain, with an emphasis on understanding underpinning mechanisms. We present a call to action to researchers and funders to target these priorities.
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Affiliation(s)
- Zoe Paskins
- Primary Care Centre Versus Arthritis, Keele University, Keele, UK
| | | | - Fay Manning
- School of Medicine, Keele University, Keele, UK
- College of Medicine and Health, University of Exeter, Exeter, UK
| | - David A Andersson
- Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Tim Barlow
- Department of Orthopaedics, Wrightington Hospital, Wigan, UK
| | | | | | | | - Emma M Clark
- Bristol Medical School, University of Bristol, UK
| | | | - Malvika Gulati
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | | | - Richard K Jones
- Centre for Health Sciences Research, University of Salford, Manchester, UK
| | - John Loughlin
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | | | - Maura McCarron
- Department of Rheumatology, Belfast Health and Social Care Trust, Belfast, UK
| | - Neil L Millar
- Institute of Infection, Immunity and Inflammation, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Hemant Pandit
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK
| | - George Peat
- Primary Care Centre Versus Arthritis, Keele University, Keele, UK
| | - Stephen M Richardson
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK
| | - Emma J Salt
- Primary Care Centre Versus Arthritis, Keele University, Keele, UK
- University Hospitals of Derby and Burton NHS Foundation Trust, Derby, UK
| | | | - Linda Troeberg
- Norwich Medical School, University of East Anglia, Norwich, UK
| | - Ruth K Wilcox
- Institute of Medical and Biological Engineering, University of Leeds, Leeds, UK
| | - Elspeth Wise
- Talbot Medical Centre, South Shields & Primary Care Rheumatology and Musculoskeletal Medicine Society, South Shields, UK
| | | | - Fiona E Watt
- Department of Immunology and Inflammation, Imperial College London, London, UK
- Correspondence to: Dr Fiona E Watt, Department of Immunology and Inflammation, Hammersmith Campus, Imperial College London, London W12 0NN, UK
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7
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Berwick RJ, Andersson DA, Goebel A, Marshall A. After-Sensations and Lingering Pain following Examination in Patients with Fibromyalgia Syndrome. Pain Med 2022; 23:1928-1938. [PMID: 35652761 DOI: 10.1093/pm/pnac089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 05/05/2022] [Accepted: 05/26/2022] [Indexed: 11/13/2022]
Abstract
Fibromyalgia syndrome (FMS) is a chronic widespread pain condition with mixed peripheral and central contributions. Patients display hypersensitivities to a spectrum of stimuli. Patients' blunt pressure pain thresholds are typically reduced, and sometimes (∼15%) gentle brushstroke induces allodynia. However, after-sensations following these stimuli have not, to our knowledge, been reported. We examined the perception of blunt pressure and 'pleasant touch' in FMS. Patients were first interviewed and completed standard psychometric questionnaires. We then measured their sensitivity to blunt pressure and perception of pleasant touch including after-sensations; patients were followed for five days evaluating lingering pain from blunt pressure. We recruited 51 FMS patients and 16 pain-free controls (HC) at a UK Pain Management Centre. Forty-four patients completed the after-sensation protocol. Most patients reported pain after application of less mechanical pressure than HCs; median arm and leg thresholds were 167 kPa and 233 kPa. Eighty-four percent (31/37) of patients reported ongoing pain at the site of pressure application one day after testing, and 49% (18/37) still perceived pain at five days. After-sensations following brushstroke were common in the FMS group, reported by 77% (34/44) compared to 25% (4/16) of HCs; 34% (15/44) patients, but no HCs, perceived these after-sensations as uncomfortable. For FMS patients who experienced after-sensations, brushstroke-pleasantness ratings were reduced, and skin was often an important site of pain. Pain after blunt pressure assessment typically lingers for several days. After-sensations following brushstroke stimulation is a previously unreported FMS phenomenon. They are associated with tactile anhedonia and may identify a clinically distinct subgroup.
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Affiliation(s)
- Richard J Berwick
- Pain Research Institute, University of Liverpool, UK.,Walton Centre, Longmore Lane, Liverpool, UK
| | | | - Andreas Goebel
- Pain Research Institute, University of Liverpool, UK.,Walton Centre, Longmore Lane, Liverpool, UK
| | - Andrew Marshall
- Pain Research Institute, University of Liverpool, UK.,Walton Centre, Longmore Lane, Liverpool, UK
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8
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Paskins Z, Farmer CE, Jones RK, Clark A, Troeberg L, Pandit H, Richardson SM, Loughlin J, Brown CA, Taylor EJ, Le Maitre CL, Wilcox RK, Bishop FL, Salt E, Clark EM, Andersson DA, McCarron M, Mason DJ, Wilkinson CM, Barlow T, Peat GM, Watt FE. P100 Research priorities to reduce the impact of musculoskeletal disorders. Rheumatology (Oxford) 2022. [DOI: 10.1093/rheumatology/keac133.099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background/Aims
Involving research users in setting priorities for research is essential to ensure research outcomes are patient-centred and to maximise research value and impact. In 2019, Versus Arthritis convened a Musculoskeletal Disorders (MSKD) Research Advisory Group (RAG) which included 25 members: people with musculoskeletal conditions, researchers and healthcare professionals. The RAG identified a need for a research prioritisation exercise for adult non-inflammatory MSKD.
Methods
The Child Health and Nutrition Research Initiative (CHNRI) method was selected. The MSKD RAG identified, through consensus, four research Domains: Mechanisms of Disease; Diagnosis and Impact; Living Well with MSK disorders and Successful Translation. Following ethical approval, an initial electronic survey was distributed to stakeholders (people with musculoskeletal conditions, researchers, healthcare professionals, industry, research funders, healthcare providers, government and charities) asking for important research uncertainties in the four domains. Uncertainties were organised into themes and refined into research questions using a series of MSKD RAG workshops. Research questions underwent lay review to optimise readability. A second e-survey was distributed to stakeholders as above, where participants were asked to score each research question for two criteria, importance and impact, on a 1-10 numeric rating scale. Median criterion scores for impact and importance were calculated for each question and summed to create a total score. Research questions were ranked according to total score.
Results
The first survey had 209 respondents, who described 1290 research uncertainties, which were refined into 68 research questions. 285 people responded to the second survey, of which 189 fully completed. 74(39.2%) were public/lay responders, 48(25.4%) researchers, 43(22.8%) clinicians, 24(12.6%) other/unrecorded. The research questions, total scores and rankings are summarised in Table 1. Total scores ranged from 12 to 18 (maximum possible score 20).
Conclusion
For the first time, we have summarised priorities for research across MSKD, from discovery science to applied clinical and health research, including translation. Key priorities include developing and testing new treatments, better targeting of treatments, early diagnosis, prevention and better understanding and management of pain, with an emphasis on understanding the underpinning mechanisms. We present a call to action to researchers and funders to target these priorities.
Disclosure
Z. Paskins: Grants/research support; NIHR, Versus Arthritis, Royal Osteoporosis Society. C.E. Farmer: None. R.K. Jones: None. A. Clark: None. L. Troeberg: Grants/research support; Versus Arthritis. H. Pandit: Consultancies; Depuy J&J, Zimmer Biomet, Smith and Nephew, Medacta International, Meril Life, JRI Orthopaedics, Invibio and Kennedy’s Law. Grants/research support; NIHR, VA (Versus Arthritis) and UKIERI (UK India Education and Research Initiative). S.M. Richardson: None. J. Loughlin: None. C.A. Brown: Grants/research support; Versus Arthrtitis. E.J. Taylor: None. C.L. Le Maitre: None. R.K. Wilcox: Grants/research support; EPSRC, Versus Arthritis, NIHR, DePuy Synthes. F.L. Bishop: None. E. Salt: None. E.M. Clark: Grants/research support; Versus Arthritis, NIHR. Other; I am Associate Editor of Journal of Bone and Mineral Research Plus for which I receive a salary, I am part of the Lot 2 provider for analysis of the national Joint Registry of England and Wales, funded by HQIP. D.A. Andersson: None. M. McCarron: None. D.J. Mason: None. C.M. Wilkinson: None. T. Barlow: None. G.M. Peat: None. F.E. Watt: Consultancies; Pfizer.
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Affiliation(s)
- Zoe Paskins
- School of Medicine, Keele University, Keele, UNITED KINGDOM
| | | | - Richard K Jones
- Centre for Health Sciences Research, University of Salford, Manchester, UNITED KINGDOM
| | - Amanda Clark
- Versus Arthritis, Versus Arthritis, Chesterfield, UNITED KINGDOM
| | - Linda Troeberg
- Norwich Medical School, University of East Anglia, Norwich, UNITED KINGDOM
| | - Hemant Pandit
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UNITED KINGDOM
| | - Stephen M Richardson
- School of Biological Sciences, University of Manchester, Manchester, UNITED KINGDOM
| | - John Loughlin
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, UNITED KINGDOM
| | - Christopher A Brown
- Department of Psychology, University of Liverpool, Liverpool, UNITED KINGDOM
| | | | - Christine L Le Maitre
- Biomedical Sciences Research Centre, Sheffield Hallam University, Sheffield, UNITED KINGDOM
| | - Ruth K Wilcox
- Institute of Medical and Biological Engineering, University of Leeds, Leeds, UNITED KINGDOM
| | - Felicity L Bishop
- School of Psychology, University of Southampton, Southampton, UNITED KINGDOM
| | - Emma Salt
- Physiotherapy Department, University Hospitals of Derby and Burton NHS Foundation Trust, Derby, UNITED KINGDOM
| | - Emma M Clark
- Translational health Sciences, University of Bristol, Bristol, UNITED KINGDOM
| | | | - Maura McCarron
- Rheumatology, Belfast Health and Social Care Trust, Belfast, UNITED KINGDOM
| | - Deborah J Mason
- School of Biosciences, Cardiff University, Cardiff, UNITED KINGDOM
| | - Colin M Wilkinson
- Versus Arthritis, Versus Arthritis, Stockton-on-Tees, UNITED KINGDOM
| | - Timothy Barlow
- Orthopaedics, Wrightington Hospital, Wigan, UNITED KINGDOM
| | - George M Peat
- School of Medicine, Keele University, Keele, UNITED KINGDOM
| | - Fiona E Watt
- Department of Immunology and Inflammation, Imperial College, London, UNITED KINGDOM
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9
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Goebel A, Krock E, Gentry C, Israel MR, Jurczak A, Urbina CM, Sandor K, Vastani N, Maurer M, Cuhadar U, Sensi S, Nomura Y, Menezes J, Baharpoor A, Brieskorn L, Sandström A, Tour J, Kadetoff D, Haglund L, Kosek E, Bevan S, Svensson CI, Andersson DA. Passive transfer of fibromyalgia symptoms from patients to mice. J Clin Invest 2021; 131:e144201. [PMID: 34196305 DOI: 10.1172/jci144201] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 05/11/2021] [Indexed: 12/25/2022] Open
Abstract
Fibromyalgia syndrome (FMS) is characterized by widespread pain and tenderness, and patients typically experience fatigue and emotional distress. The etiology and pathophysiology of fibromyalgia are not fully explained and there are no effective drug treatments. Here we show that IgG from FMS patients produced sensory hypersensitivity by sensitizing nociceptive neurons. Mice treated with IgG from FMS patients displayed increased sensitivity to noxious mechanical and cold stimulation, and nociceptive fibers in skin-nerve preparations from mice treated with FMS IgG displayed an increased responsiveness to cold and mechanical stimulation. These mice also displayed reduced locomotor activity, reduced paw grip strength, and a loss of intraepidermal innervation. In contrast, transfer of IgG-depleted serum from FMS patients or IgG from healthy control subjects had no effect. Patient IgG did not activate naive sensory neurons directly. IgG from FMS patients labeled satellite glial cells and neurons in vivo and in vitro, as well as myelinated fiber tracts and a small number of macrophages and endothelial cells in mouse dorsal root ganglia (DRG), but no cells in the spinal cord. Furthermore, FMS IgG bound to human DRG. Our results demonstrate that IgG from FMS patients produces painful sensory hypersensitivities by sensitizing peripheral nociceptive afferents and suggest that therapies reducing patient IgG titers may be effective for fibromyalgia.
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Affiliation(s)
- Andreas Goebel
- Walton Centre NHS Foundation Trust, Liverpool, United Kingdom.,Pain Research Institute, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Emerson Krock
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Clive Gentry
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
| | - Mathilde R Israel
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
| | - Alexandra Jurczak
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Carlos Morado Urbina
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Katalin Sandor
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Nisha Vastani
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
| | - Margot Maurer
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
| | - Ulku Cuhadar
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
| | - Serena Sensi
- Pain Research Institute, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Yuki Nomura
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Joana Menezes
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Azar Baharpoor
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Louisa Brieskorn
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Angelica Sandström
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jeanette Tour
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Diana Kadetoff
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Stockholm Spine Center, Upplands Väsby, Sweden
| | - Lisbet Haglund
- Department of Surgery, Division of Orthopaedic Surgery, McGill University, Montreal, Quebec, Canada
| | - Eva Kosek
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Stuart Bevan
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
| | - Camilla I Svensson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - David A Andersson
- King's College London, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, Guy's Campus, London, United Kingdom
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10
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Alkhatib O, da Costa R, Gentry C, Quallo T, Bevan S, Andersson DA. Promiscuous G-Protein-Coupled Receptor Inhibition of Transient Receptor Potential Melastatin 3 Ion Channels by Gβγ Subunits. J Neurosci 2019; 39:7840-7852. [PMID: 31451581 PMCID: PMC6774412 DOI: 10.1523/jneurosci.0882-19.2019] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/19/2019] [Accepted: 08/14/2019] [Indexed: 11/21/2022] Open
Abstract
Transient receptor potential melastatin 3 (TRPM3) is a nonselective cation channel that is inhibited by Gβγ subunits liberated following activation of Gαi/o protein-coupled receptors. Here, we demonstrate that TRPM3 channels are also inhibited by Gβγ released from Gαs and Gαq Activation of the Gs-coupled adenosine 2B receptor and the Gq-coupled muscarinic acetylcholine M1 receptor inhibited the activity of TRPM3 heterologously expressed in HEK293 cells. This inhibition was prevented when the Gβγ sink βARK1-ct (C terminus of β-adrenergic receptor kinase-1) was coexpressed with TRPM3. In neurons isolated from mouse dorsal root ganglion (DRG), native TRPM3 channels were inhibited by activating Gs-coupled prostaglandin-EP2 and Gq-coupled bradykinin B2 (BK2) receptors. The Gi/o inhibitor pertussis toxin and inhibitors of PKA and PKC had no effect on EP2- and BK2-mediated inhibition of TRPM3, demonstrating that the receptors did not act through Gαi/o or through the major protein kinases activated downstream of G-protein-coupled receptor (GPCR) activation. When DRG neurons were dialyzed with GRK2i, which sequesters free Gβγ protein, TRPM3 inhibition by EP2 and BK2 was significantly reduced. Intraplantar injections of EP2 or BK2 agonists inhibited both the nocifensive response evoked by TRPM3 agonists, and the heat hypersensitivity produced by Freund's Complete Adjuvant (FCA). Furthermore, FCA-induced heat hypersensitivity was completely reversed by the selective TRPM3 antagonist ononetin in WT mice and did not develop in Trpm3-/- mice. Our results demonstrate that TRPM3 is subject to promiscuous inhibition by Gβγ protein in heterologous expression systems, primary neurons and in vivo, and suggest a critical role for this ion channel in inflammatory heat hypersensitivity.SIGNIFICANCE STATEMENT The ion channel TRPM3 is widely expressed in the nervous system. Recent studies showed that Gαi/o-coupled GPCRs inhibit TRPM3 through a direct interaction between Gβγ subunits and TRPM3. Since Gβγ proteins can be liberated from other Gα subunits than Gαi/o, we examined whether activation of Gs- and Gq-coupled receptors also influence TRPM3 via Gβγ. Our results demonstrate that activation of Gs- and Gq-coupled GPCRs in recombinant cells and sensory neurons inhibits TRPM3 via Gβγ liberation. We also demonstrated that Gs- and Gq-coupled receptors inhibit TRPM3 in vivo, thereby reducing pain produced by activation of TRPM3, and inflammatory heat hypersensitivity. Our results identify Gβγ inhibition of TRPM3 as an effector mechanism shared by the major Gα subunits.
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Affiliation(s)
- Omar Alkhatib
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom, and
| | - Robson da Costa
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom, and
- School of Pharmacy, Universidade Federal do Rio de Janeiro, 21941-908 Rio de Janeiro, Brazil
| | - Clive Gentry
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom, and
| | - Talisia Quallo
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom, and
| | - Stuart Bevan
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom, and
| | - David A Andersson
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom, and
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11
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Samin AJ, Andersson DA, Holby EF, Uberuaga BP. On the role of electro-migration in the evolution of radiation damage in nanostructured ionic materials. Electrochem commun 2018. [DOI: 10.1016/j.elecom.2018.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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12
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Vastani N, Guenther F, Gentry C, Austin AL, King AJ, Bevan S, Andersson DA. Impaired Nociception in the Diabetic Ins2+/Akita Mouse. Diabetes 2018; 67:1650-1662. [PMID: 29875100 DOI: 10.2337/db17-1306] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 05/18/2018] [Indexed: 11/13/2022]
Abstract
The mechanisms responsible for painful and insensate diabetic neuropathy are not completely understood. Here, we have investigated sensory neuropathy in the Ins2+/Akita mouse, a hereditary model of diabetes. Akita mice become diabetic soon after weaning, and we show that this is accompanied by an impaired mechanical and thermal nociception and a significant loss of intraepidermal nerve fibers. Electrophysiological investigations of skin-nerve preparations identified a reduced rate of action potential discharge in Ins2+/Akita mechanonociceptors compared with wild-type littermates, whereas the function of low-threshold A-fibers was essentially intact. Studies of isolated sensory neurons demonstrated a markedly reduced heat responsiveness in Ins2+/Akita dorsal root ganglion (DRG) neurons, but a mostly unchanged function of cold-sensitive neurons. Restoration of normal glucose control by islet transplantation produced a rapid recovery of nociception, which occurred before normoglycemia had been achieved. Islet transplantation also restored Ins2+/Akita intraepidermal nerve fiber density to the same level as wild-type mice, indicating that restored insulin production can reverse both sensory and anatomical abnormalities of diabetic neuropathy in mice. The reduced rate of action potential discharge in nociceptive fibers and the impaired heat responsiveness of Ins2+/Akita DRG neurons suggest that ionic sensory transduction and transmission mechanisms are modified by diabetes.
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MESH Headings
- Action Potentials
- Amino Acid Substitution
- Animals
- Behavior, Animal
- Cells, Cultured
- Diabetes Mellitus/blood
- Diabetes Mellitus/surgery
- Diabetic Neuropathies/metabolism
- Diabetic Neuropathies/pathology
- Diabetic Neuropathies/physiopathology
- Diabetic Neuropathies/prevention & control
- Epidermis/innervation
- Epidermis/metabolism
- Epidermis/pathology
- Epidermis/physiopathology
- Ganglia, Spinal/metabolism
- Ganglia, Spinal/pathology
- Ganglia, Spinal/physiopathology
- Heterozygote
- Insulin/genetics
- Insulin/metabolism
- Islets of Langerhans Transplantation
- Kidney
- Male
- Mechanoreceptors/metabolism
- Mechanoreceptors/pathology
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Nerve Fibers, Unmyelinated/metabolism
- Nerve Fibers, Unmyelinated/pathology
- Pain Measurement
- Somatosensory Disorders/complications
- Somatosensory Disorders/metabolism
- Somatosensory Disorders/physiopathology
- Somatosensory Disorders/prevention & control
- Thermoreceptors/metabolism
- Thermoreceptors/pathology
- Thermoreceptors/physiopathology
- Transplantation, Heterotopic
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Affiliation(s)
- Nisha Vastani
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, U.K
| | - Franziska Guenther
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, U.K
- Institut für Physiologie und Pathophysiologie, Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Clive Gentry
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, U.K
| | - Amazon L Austin
- Diabetes & Nutritional Sciences Division, King's College London, London, U.K
| | - Aileen J King
- Diabetes & Nutritional Sciences Division, King's College London, London, U.K
| | - Stuart Bevan
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, U.K
| | - David A Andersson
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, U.K.
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13
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Quallo T, Alkhatib O, Gentry C, Andersson DA, Bevan S. G protein βγ subunits inhibit TRPM3 ion channels in sensory neurons. eLife 2017; 6. [PMID: 28826490 PMCID: PMC5593501 DOI: 10.7554/elife.26138] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 07/24/2017] [Indexed: 02/07/2023] Open
Abstract
Transient receptor potential (TRP) ion channels in peripheral sensory neurons are functionally regulated by hydrolysis of the phosphoinositide PI(4,5)P2 and changes in the level of protein kinase mediated phosphorylation following activation of various G protein coupled receptors. We now show that the activity of TRPM3 expressed in mouse dorsal root ganglion (DRG) neurons is inhibited by agonists of the Gi-coupled µ opioid, GABA-B and NPY receptors. These agonist effects are mediated by direct inhibition of TRPM3 by Gβγ subunits, rather than by a canonical cAMP mediated mechanism. The activity of TRPM3 in DRG neurons is also negatively modulated by tonic, constitutive GPCR activity as TRPM3 responses can be potentiated by GPCR inverse agonists. GPCR regulation of TRPM3 is also seen in vivo where Gi/o GPCRs agonists inhibited and inverse agonists potentiated TRPM3 mediated nociceptive behavioural responses. DOI:http://dx.doi.org/10.7554/eLife.26138.001 TRPM3 belongs to a family of channel proteins that allow sodium and calcium ions to enter cells by forming pores in cell membranes. TRPM3 is found on the cell membranes of nerve cells; when ions flow into the nerves through the TRPM3 pores it triggers an electrical impulse. TRPM3 is responsible for helping us to detect heat, and mice without this protein find it difficult to sense painfully hot temperatures. Mice lacking TRPM3 also respond to other kinds of pain differently. Normally, a mouse with an injured paw becomes more sensitive to warm and hot temperatures, but this does not happen in mice that do not have TRPM3. When activated, other proteins called G-protein coupled receptors (or GPCRs for short) can make some members of this family of channel proteins more or less likely to open their pore. This in turn increases or decreases the flow of ions through the pore, respectively. Yet it was not clear if GPCRs also affect TRPM3 channels on the membranes of nerve cells. Quallo et al. have now discovered that “switching on” different GPCR proteins in sensory nerve cells from mice greatly reduces the flow of calcium ions though TRPM3 channels. The experiments made use of two pain-killing drugs, namely morphine and baclofen, and a molecule called neuropeptide Y to activate different GPCRs. GPCRs interact with a group of small proteins called G-proteins that, when activated by the receptor, split into two subunits, known as the α subunit and the βγ subunit. Once detached these subunits are free to act as messengers and interact with other proteins in the cell membrane. Quallo et al. found that TRPM3 is one of a small group of proteins that interact with the βγ subunits of the G-protein, which can explain how “switching on” GPCRs reduces the activity of TRPM3. Two independent studies by Dembla, Behrendt et al. and Badheka, Yudin et al. also report similar findings. There is currently a need to find more effective treatments for people suffering from long-term pain conditions and it has become clear that TRPM3 channels are involved in sensing both pain and temperature. These new findings show that drugs already used in the treatment of pain can dramatically change how TRPM3 works. These results might help scientists to find drugs that work in a similar way to dial down the activity of TRPM3 and to combat pain. Though first it will be important to confirm these new findings in human nerve cells. DOI:http://dx.doi.org/10.7554/eLife.26138.002
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Affiliation(s)
- Talisia Quallo
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Omar Alkhatib
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Clive Gentry
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - David A Andersson
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Stuart Bevan
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
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14
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Mathie K, Lainer J, Spreng S, Dawid C, Andersson DA, Bevan S, Hofmann T. Structure-Pungency Relationships and TRP Channel Activation of Drimane Sesquiterpenes in Tasmanian Pepper (Tasmannia lanceolata). J Agric Food Chem 2017; 65:5700-5712. [PMID: 28657737 DOI: 10.1021/acs.jafc.7b02356] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Sensory-guided fractionation of extracts of Tasmanian pepper berries revealed 20 drimane sesquiterpens, among which polygodial, warburganal, and 1β-acetoxy-9-deoxy-isomuzigadial exhibited the lowest pungency threshold concentrations on the tongue surface (0.6-2.8 nmol/cm2) and elicited a dose-dependent calcium influx into mTRPA1 expressing CHO cells with the lowest EC50 values (4.5 ± 1.0 to 16.7 ± 7.5 μmol/L) and a good correlation to oral pungency thresholds (R2 = 0.986, linear regression). Calcium imaging assays demonstrated these chemosensates to induce a calcium influx into cultured trigeminal neurons prepared from wildtype (TRPA1+/+) mice, whereas no calcium influx was observed in neurons from TRPA1 knockout mice (TRPA1-/-), thus confirming the α,β-unsaturated 1,4-dialdehyde structure to be the required structural motif for a low oral puncency thresholds and activation of the Transient Receptor Potential Channel A1 (TRPA1). Time-resolved NMR experiments confirmed the pungency mediating mechanism for electrophilic drimane sesquiterpene dialdehydes to be different from that found for other electrophilic pungent agents like isothiocyanates, which have been shown to undergo a covalent binding with cysteine residues in TRPA1. Instead, the high-impact chemosensates polygodial, warburganal, and 1β-acetoxy-9-deoxy-isomuzigadial showed immediate reactivity with the ε-amino group of lysine side chains to give pyrrole-type conjugates, thus showing evidence for TRPA1 activation by covalent lysine modification.
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Affiliation(s)
- Klaus Mathie
- Chair of Food Chemistry and Molecular Sensory Science, Technische Universität München , Lise-Meitner-Straße 34, D-85350 Freising, Germany , and
| | - Johanna Lainer
- Chair of Food Chemistry and Molecular Sensory Science, Technische Universität München , Lise-Meitner-Straße 34, D-85350 Freising, Germany , and
| | - Stefan Spreng
- Chair of Food Chemistry and Molecular Sensory Science, Technische Universität München , Lise-Meitner-Straße 34, D-85350 Freising, Germany , and
| | - Corinna Dawid
- Chair of Food Chemistry and Molecular Sensory Science, Technische Universität München , Lise-Meitner-Straße 34, D-85350 Freising, Germany , and
| | - David A Andersson
- Kings's College London , Wolfron Centre for Age-Related Diseases, London SE1 1UL, United Kingdom
| | - Stuart Bevan
- Kings's College London , Wolfron Centre for Age-Related Diseases, London SE1 1UL, United Kingdom
| | - Thomas Hofmann
- Chair of Food Chemistry and Molecular Sensory Science, Technische Universität München , Lise-Meitner-Straße 34, D-85350 Freising, Germany , and
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15
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Vathonne E, Andersson DA, Freyss M, Perriot R, Cooper MWD, Stanek CR, Bertolus M. Determination of Krypton Diffusion Coefficients in Uranium Dioxide Using Atomic Scale Calculations. Inorg Chem 2016; 56:125-137. [DOI: 10.1021/acs.inorgchem.6b01560] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Emerson Vathonne
- CEA, DEN, DEC, Centre de Cadarache, 13108 Saint-Paul-lez-Durance, France
| | - David A. Andersson
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Michel Freyss
- CEA, DEN, DEC, Centre de Cadarache, 13108 Saint-Paul-lez-Durance, France
| | - Romain Perriot
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Michael W. D. Cooper
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Christopher R. Stanek
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Marjorie Bertolus
- CEA, DEN, DEC, Centre de Cadarache, 13108 Saint-Paul-lez-Durance, France
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16
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Galvin COT, Cooper MWD, Fossati PCM, Stanek CR, Grimes RW, Andersson DA. Pipe and grain boundary diffusion of He in UO2. J Phys Condens Matter 2016; 28:405002. [PMID: 27537341 DOI: 10.1088/0953-8984/28/40/405002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Molecular dynamics simulations have been conducted to study the effects of dislocations and grain boundaries on He diffusion in [Formula: see text]. Calculations were carried out for the {1 0 0}, {1 1 0} and {1 1 1} [Formula: see text] edge dislocations, the screw [Formula: see text] dislocation and Σ5, Σ13, Σ19 and Σ25 tilt grain boundaries. He diffusivity as a function of distance from the dislocation core and grain boundaries was investigated for the temperature range 2300-3000 K. An enhancement in diffusivity was predicted within 20 Å of the dislocations or grain boundaries. Further investigation showed that He diffusion in the edge dislocations follows anisotropic behaviour along the dislocation core, suggesting that pipe diffusion occurs. An Arrhenius plot of He diffusivity against the inverse of temperature was also presented and the activation energy calculated for each structure, as a function of distance from the dislocation or grain boundary.
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Affiliation(s)
- C O T Galvin
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
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17
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Cooper MWD, Kuganathan N, Burr PA, Rushton MJD, Grimes RW, Stanek CR, Andersson DA. Development of Xe and Kr empirical potentials for CeO2, ThO2, UO2 and PuO2, combining DFT with high temperature MD. J Phys Condens Matter 2016; 28:405401. [PMID: 27549186 DOI: 10.1088/0953-8984/28/40/405401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The development of embedded atom method (EAM) many-body potentials for actinide oxides and associated mixed oxide (MOX) systems has motivated the development of a complementary parameter set for gas-actinide and gas-oxygen interactions. A comprehensive set of density functional theory (DFT) calculations were used to study Xe and Kr incorporation at a number of sites in CeO2, ThO2, UO2 and PuO2. These structures were used to fit a potential, which was used to generate molecular dynamics (MD) configurations incorporating Xe and Kr at 300 K, 1500 K, 3000 K and 5000 K. Subsequent matching to the forces predicted by DFT for these MD configurations was used to refine the potential set. This fitting approach ensured weighted fitting to configurations that are thermodynamically significant over a broad temperature range, while avoiding computationally expensive DFT-MD calculations. The resultant gas potentials were validated against DFT trapping energies and are suitable for simulating combinations of Xe and Kr in solid solutions of CeO2, ThO2, UO2 and PuO2, providing a powerful tool for the atomistic simulation of conventional nuclear reactor fuel UO2 as well as advanced MOX fuels.
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Affiliation(s)
- M W D Cooper
- Materials Science and Technology Division, Los Alamos National Laboratory, PO Box 1663, Los Alamos, NM 87545, USA
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Butorin SM, Modin A, Vegelius JR, Suzuki MT, Oppeneer PM, Andersson DA, Shuh DK. Local Symmetry Effects in Actinide 4f X-ray Absorption in Oxides. Anal Chem 2016; 88:4169-73. [PMID: 27008406 DOI: 10.1021/acs.analchem.5b04380] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A systematic X-ray absorption study at actinide N6,7 (4f → 6d transitions) edges was performed for light-actinide oxides including data obtained for the first time for NpO2, PuO2, and UO3. The measurements were supported by ab initio calculations based on local-density-approximation with added 5f-5f Coulomb interaction (LDA+U). Improved energy resolution compared to common experiments at actinide L(2,3) (2p → 6d transitions) edges allowed us to resolve the major structures of the unoccupied 6d density of states (DOS) and estimate the crystal-field splittings in the 6d shell directly from the spectra of light-actinide dioxides. The measurements demonstrated an enhanced sensitivity of the N(6,7) spectral shape to changes in the compound crystal structure. For nonstoichiometric NpO(2-x), the filling of the entire band gap with Np 6d states was observed thus supporting a phase coexistence of Np metal and stoichiometric NpO2 which is in agreement with the tentative Np-O phase diagram.
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Affiliation(s)
- Sergei M Butorin
- Department of Physics and Astronomy, Uppsala University , P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Anders Modin
- Department of Physics and Astronomy, Uppsala University , P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Johan R Vegelius
- Department of Physics and Astronomy, Uppsala University , P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Michi-To Suzuki
- Department of Physics and Astronomy, Uppsala University , P.O. Box 516, SE-751 20 Uppsala, Sweden.,RIKEN Center for Emergent Matter Science , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Peter M Oppeneer
- Department of Physics and Astronomy, Uppsala University , P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - David A Andersson
- Materials Science in Radiation and Dynamical Extremes, Materials Science and Technology Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - David K Shuh
- Chemical Sciences Division, Lawrence Berkeley National Laboratory , MS 70A1150, One Cyclotron Road, Berkeley, California 94720, United States
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Conradson SD, Gilbertson SM, Daifuku SL, Kehl JA, Durakiewicz T, Andersson DA, Bishop AR, Byler DD, Maldonado P, Oppeneer PM, Valdez JA, Neidig ML, Rodriguez G. Possible Demonstration of a Polaronic Bose-Einstein(-Mott) Condensate in UO2(+x) by Ultrafast THz Spectroscopy and Microwave Dissipation. Sci Rep 2015; 5:15278. [PMID: 26472071 PMCID: PMC4607891 DOI: 10.1038/srep15278] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 09/21/2015] [Indexed: 11/23/2022] Open
Abstract
Bose-Einstein condensates (BECs) composed of polarons would be an advance because they would combine coherently charge, spin, and a crystal lattice. Following our earlier report of unique structural and spectroscopic properties, we now identify potentially definitive evidence for polaronic BECs in photo- and chemically doped UO2(+x) on the basis of exceptional coherence in the ultrafast time dependent terahertz absorption and microwave spectroscopy results that show collective behavior including dissipation patterns whose precedents are condensate vortex and defect disorder and condensate excitations. That some of these signatures of coherence in an atom-based system extend to ambient temperature suggests a novel mechanism that could be a synchronized, dynamical, disproportionation excitation, possibly via the solid state analog of a Feshbach resonance that promotes the coherence. Such a mechanism would demonstrate that the use of ultra-low temperatures to establish the BEC energy distribution is a convenience rather than a necessity, with the actual requirement for the particles being in the same state that is not necessarily the ground state attainable by other means. A macroscopic quantum object created by chemical doping that can persist to ambient temperature and resides in a bulk solid would be revolutionary in a number of scientific and technological fields.
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Affiliation(s)
- Steven D Conradson
- Synchrotron Soleil, L'Orme des Merisiers Saint-Aubin, BP 48 91192, Gif-sur-Yvette, France
| | | | | | - Jeffrey A Kehl
- Department of Chemistry, University of Rochester, NY 14627, USA
| | - Tomasz Durakiewicz
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | - David A Andersson
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | - Alan R Bishop
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | - Darrin D Byler
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | - Pablo Maldonado
- Department of Physics and Astronomy, Uppsala University, S-75120, Uppsala, Sweden
| | - Peter M Oppeneer
- Department of Physics and Astronomy, Uppsala University, S-75120, Uppsala, Sweden
| | - James A Valdez
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | | | - George Rodriguez
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
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Quallo T, Vastani N, Horridge E, Gentry C, Parra A, Moss S, Viana F, Belmonte C, Andersson DA, Bevan S. TRPM8 is a neuronal osmosensor that regulates eye blinking in mice. Nat Commun 2015; 6:7150. [PMID: 25998021 PMCID: PMC4455064 DOI: 10.1038/ncomms8150] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 04/13/2015] [Indexed: 01/23/2023] Open
Abstract
Specific peripheral sensory neurons respond to increases in extracellular osmolality but the mechanism responsible for excitation is unknown. Here we show that small increases in osmolality excite isolated mouse dorsal root ganglion (DRG) and trigeminal ganglion (TG) neurons expressing the cold-sensitive TRPM8 channel (transient receptor potential channel, subfamily M, member 8). Hyperosmotic responses were abolished by TRPM8 antagonists, and were absent in DRG and TG neurons isolated from Trpm8(-/-) mice. Heterologously expressed TRPM8 was activated by increased osmolality around physiological levels and inhibited by reduced osmolality. Electrophysiological studies in a mouse corneal preparation demonstrated that osmolality regulated the electrical activity of TRPM8-expressing corneal afferent neurons. Finally, the frequency of eye blinks was reduced in Trpm8(-/-) compared with wild-type mice and topical administration of a TRPM8 antagonist reduced blinking in wild-type mice. Our findings identify TRPM8 as a peripheral osmosensor responsible for the regulation of normal eye-blinking in mice.
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Affiliation(s)
- Talisia Quallo
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
| | - Nisha Vastani
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
| | - Elisabeth Horridge
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
| | - Clive Gentry
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
| | - Andres Parra
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, San Juan de Alicante E-03550, Spain
| | - Sian Moss
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
| | - Felix Viana
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, San Juan de Alicante E-03550, Spain
| | - Carlos Belmonte
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-CSIC, San Juan de Alicante E-03550, Spain
| | - David A. Andersson
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
| | - Stuart Bevan
- Wolfson Centre for Age Related Diseases, King's College London, London SE1 1UL, UK
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Andersson DA, Filipović MR, Gentry C, Eberhardt M, Vastani N, Leffler A, Reeh P, Bevan S. Streptozotocin Stimulates the Ion Channel TRPA1 Directly: INVOLVEMENT OF PEROXYNITRITE. J Biol Chem 2015; 290:15185-96. [PMID: 25903127 DOI: 10.1074/jbc.m115.644476] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Indexed: 01/01/2023] Open
Abstract
Streptozotocin (STZ)-induced diabetes is the most commonly used animal model of diabetes. Here, we have demonstrated that intraplantar injections of low dose STZ evoked acute polymodal hypersensitivities in mice. These hypersensitivities were inhibited by a TRPA1 antagonist and were absent in TRPA1-null mice. In wild type mice, systemic STZ treatment (180 mg/kg) evoked a loss of cold and mechanical sensitivity within an hour of injection, which lasted for at least 10 days. In contrast, Trpa1(-/-) mice developed mechanical, cold, and heat hypersensitivity 24 h after STZ. The TRPA1-dependent sensory loss produced by STZ occurs before the onset of diabetes and may thus not be readily distinguished from the similar sensory abnormalities produced by the ensuing diabetic neuropathy. In vitro, STZ activated TRPA1 in isolated sensory neurons, TRPA1 cell lines, and membrane patches. Mass spectrometry studies revealed that STZ oxidizes TRPA1 cysteines to disulfides and sulfenic acids. Furthermore, incubation of tyrosine with STZ resulted in formation of dityrosine, suggesting formation of peroxynitrite. Functional analysis of TRPA1 mutants showed that cysteine residues that were oxidized by STZ were important for TRPA1 responsiveness to STZ. Our results have identified oxidation of TRPA1 cysteine residues, most likely by peroxynitrite, as a novel mechanism of action of STZ. Direct stimulation of TRPA1 complicates the interpretation of results from STZ models of diabetic sensory neuropathy and strongly argues that more refined models of diabetic neuropathy should replace the use of STZ.
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Affiliation(s)
- David A Andersson
- From the Wolfson Centre for Age-related Diseases, Hodgkin Building, Guy's Campus, King's College London, London SE1 1UL, United Kingdom,
| | - Milos R Filipović
- the Bioinorganic Chemistry Division, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 1, 91058 Erlangen, Germany
| | - Clive Gentry
- From the Wolfson Centre for Age-related Diseases, Hodgkin Building, Guy's Campus, King's College London, London SE1 1UL, United Kingdom
| | - Mirjam Eberhardt
- the Department of Anesthesiology and Intensive Care, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany, and
| | - Nisha Vastani
- From the Wolfson Centre for Age-related Diseases, Hodgkin Building, Guy's Campus, King's College London, London SE1 1UL, United Kingdom
| | - Andreas Leffler
- the Department of Anesthesiology and Intensive Care, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany, and
| | - Peter Reeh
- the Institute of Physiology and Pathophysiology, University of Erlangen-Nuremberg, Universitaetsstrasse 17, D-91054 Erlangen, Germany
| | - Stuart Bevan
- From the Wolfson Centre for Age-related Diseases, Hodgkin Building, Guy's Campus, King's College London, London SE1 1UL, United Kingdom
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Zygmunt PM, Ermund A, Movahed P, Andersson DA, Simonsen C, Jönsson BAG, Blomgren A, Birnir B, Bevan S, Eschalier A, Mallet C, Gomis A, Högestätt ED. Monoacylglycerols activate TRPV1--a link between phospholipase C and TRPV1. PLoS One 2013; 8:e81618. [PMID: 24312564 PMCID: PMC3847081 DOI: 10.1371/journal.pone.0081618] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 10/25/2013] [Indexed: 01/17/2023] Open
Abstract
Phospholipase C-mediated hydrolysis of phosphatidylinositol 4,5-bisphosphate generates diacylglycerol, inositol 1,4,5-trisphosphate and protons, all of which can regulate TRPV1 activity via different mechanisms. Here we explored the possibility that the diacylglycerol metabolites 2-arachidonoylglycerol and 1-arachidonoylglycerol, and not metabolites of these monoacylglycerols, activate TRPV1 and contribute to this signaling cascade. 2-Arachidonoylglycerol and 1-arachidonoylglycerol activated native TRPV1 on vascular sensory nerve fibers and heterologously expressed TRPV1 in whole cells and inside-out membrane patches. The monoacylglycerol lipase inhibitors methylarachidonoyl-fluorophosphonate and JZL184 prevented the metabolism of deuterium-labeled 2-arachidonoylglycerol and deuterium-labeled 1-arachidonoylglycerol in arterial homogenates, and enhanced TRPV1-mediated vasodilator responses to both monoacylglycerols. In mesenteric arteries from TRPV1 knock-out mice, vasodilator responses to 2-arachidonoylglycerol were minor. Bradykinin and adenosine triphosphate, ligands of phospholipase C-coupled membrane receptors, increased the content of 2-arachidonoylglycerol in dorsal root ganglia. In HEK293 cells expressing the phospholipase C-coupled histamine H1 receptor, exposure to histamine stimulated the formation of 2-AG, and this effect was augmented in the presence of JZL184. These effects were prevented by the diacylglycerol lipase inhibitor tetrahydrolipstatin. Histamine induced large whole cell currents in HEK293 cells co-expressing TRPV1 and the histamine H1 receptor, and the TRPV1 antagonist capsazepine abolished these currents. JZL184 increased the histamine-induced currents and tetrahydrolipstatin prevented this effect. The calcineurin inhibitor ciclosporin and the endogenous "entourage" compound palmitoylethanolamide potentiated the vasodilator response to 2-arachidonoylglycerol, disclosing TRPV1 activation of this monoacylglycerol at nanomolar concentrations. Furthermore, intracerebroventricular injection of JZL184 produced TRPV1-dependent antinociception in the mouse formalin test. Our results show that intact 2-arachidonoylglycerol and 1-arachidonoylglycerol are endogenous TRPV1 activators, contributing to phospholipase C-dependent TRPV1 channel activation and TRPV1-mediated antinociceptive signaling in the brain.
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Affiliation(s)
- Peter M. Zygmunt
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Lund University Pain Research Centre, Lund University, Lund, Sweden
- * E-mail: (PMZ); (EDH)
| | - Anna Ermund
- Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Pouya Movahed
- Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - David A. Andersson
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | | | - Bo A. G. Jönsson
- Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Anders Blomgren
- Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Bryndis Birnir
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Stuart Bevan
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Alain Eschalier
- Clermont Université, Université d'Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie, Facultés de Médecine/Pharmacie, Clermont-Ferrand, France
- Inserm, U1107 Neuro-Dol, Clermont-Ferrand, France
- CHU Clermont-Ferrand, Service de Pharmacologie, Hôpital G. Montpied, Clermont-Ferrand, France
| | - Christophe Mallet
- Clermont Université, Université d'Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie, Facultés de Médecine/Pharmacie, Clermont-Ferrand, France
- Inserm, U1107 Neuro-Dol, Clermont-Ferrand, France
| | - Ana Gomis
- Instituto de Neurociencias, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas, Sant Joan d'Alacant, Spain
| | - Edward D. Högestätt
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Lund University Pain Research Centre, Lund University, Lund, Sweden
- * E-mail: (PMZ); (EDH)
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Andersson DA, Gentry C, Light E, Vastani N, Vallortigara J, Bierhaus A, Fleming T, Bevan S. Methylglyoxal evokes pain by stimulating TRPA1. PLoS One 2013; 8:e77986. [PMID: 24167592 PMCID: PMC3805573 DOI: 10.1371/journal.pone.0077986] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 09/16/2013] [Indexed: 12/13/2022] Open
Abstract
Diabetic neuropathy is a severe complication of long-standing diabetes and one of the major etiologies of neuropathic pain. Diabetes is associated with an increased formation of reactive oxygen species and the electrophilic dicarbonyl compound methylglyoxal (MG). Here we show that MG stimulates heterologously expressed TRPA1 in CHO cells and natively expressed TRPA1 in MDCK cells and DRG neurons. MG evokes [Ca2+]i-responses in TRPA1 expressing DRG neurons but is without effect in neurons cultured from Trpa1−/− mice. Consistent with a direct, intracellular action, we show that methylglyoxal is significantly more potent as a TRPA1 agonist when applied to the intracellular face of excised membrane patches than to intact cells. Local intraplantar administration of MG evokes a pain response in Trpa1+/+ but not in Trpa1−/− mice. Furthermore, persistently increased MG levels achieved by two weeks pharmacological inhibition of glyoxalase-1 (GLO-1), the rate-limiting enzyme responsible for detoxification of MG, evokes a progressive and marked thermal (cold and heat) and mechanical hypersensitivity in wildtype but not in Trpa1−/− mice. Our results thus demonstrate that TRPA1 is required both for the acute pain response evoked by topical MG and for the long-lasting pronociceptive effects associated with elevated MG in vivo. In contrast to our observations in DRG neurons, MG evokes indistinguishable [Ca2+]i-responses in pancreatic β-cells cultured from Trpa1+/+ and Trpa1−/− mice. In vivo, the TRPA1 antagonist HC030031 impairs glucose clearance in the glucose tolerance test both in Trpa1+/+ and Trpa1−/− mice, indicating a non-TRPA1 mediated effect and suggesting that results obtained with this compound should be interpreted with caution. Our results show that TRPA1 is the principal target for MG in sensory neurons but not in pancreatic β-cells and that activation of TRPA1 by MG produces a painful neuropathy with the behavioral hallmarks of diabetic neuropathy.
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Affiliation(s)
| | - Clive Gentry
- Wolfson CARD, King’s College London, London, United Kingdom
| | - Emily Light
- Wolfson CARD, King’s College London, London, United Kingdom
| | - Nisha Vastani
- Wolfson CARD, King’s College London, London, United Kingdom
| | | | - Angelika Bierhaus
- Department of Medicine I and Clinical Chemistry, University Hospital Heidelberg, Heidelberg, Germany
| | - Thomas Fleming
- Department of Medicine I and Clinical Chemistry, University Hospital Heidelberg, Heidelberg, Germany
| | - Stuart Bevan
- Wolfson CARD, King’s College London, London, United Kingdom
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Andersson DA, Stanek CR. Mixing and non-stoichiometry in Fe–Ni–Cr–Zn–O spinel compounds: density functional theory calculations. Phys Chem Chem Phys 2013; 15:15550-64. [DOI: 10.1039/c3cp50312g] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
Hydrogen sulfide (H2S), which is produced endogenously from L-cysteine, is an irritant with pro-nociceptive actions. We have used measurements of intracellular calcium concentration, electrophysiology and behavioral measurements to show that the somatic pronociceptive actions of H2S require TRPA1. A H2S donor, NaHS, activated TRPA1 expressed in CHO cells and stimulated DRG neurons isolated from Trpa1+/+ but not Trpa1−/− mice. TRPA1 activation by NaHS was pH dependent with increased activity at acidic pH. The midpoint of the relationship between NaHS EC50 values and external pH was pH 7.21, close to the expected dissociation constant for H2S (pKa 7.04). NaHS evoked single channel currents in inside-out and cell-attached membrane patches consistent with an intracellular site of action. In behavioral experiments, intraplantar administration of NaHS and L-cysteine evoked mechanical and cold hypersensitivities in Trpa1+/+ but not in Trpa1−/− mice. The sensitizing effects of L-cysteine in wild-type mice were inhibited by a cystathionine β-synthase inhibitor, D,L-propargylglycine (PAG), which inhibits H2S formation. Mechanical hypersensitivity evoked by intraplantar injections of LPS was prevented by PAG and the TRPA1 antagonist AP-18 and was absent in Trpa1−/− mice, indicating that H2S mediated stimulation of TRPA1 is necessary for the local pronociceptive effects of LPS. The pro-nociceptive effects of intraplantar NaHS were retained in Trpv1−/− mice ruling out TRPV1 as a molecular target. In behavioral studies, NaHS mediated sensitization was also inhibited by a T-type calcium channel inhibitor, mibefradil. In contrast to the effects of NaHS on somatic sensitivity, intracolonic NaHS administration evoked similar nociceptive effects in Trpa1+/+ and Trpa1−/− mice, suggesting that the visceral pro-nociceptive effects of H2S are independent of TRPA1. In electrophysiological studies, the depolarizing actions of H2S on isolated DRG neurons were inhibited by AP-18, but not by mibefradil indicating that the primary excitatory effect of H2S on DRG neurons is TRPA1 mediated depolarization.
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Affiliation(s)
- David A. Andersson
- Wolfson Centre for Age Related Diseases, King's College London, London, United Kingdom
| | - Clive Gentry
- Wolfson Centre for Age Related Diseases, King's College London, London, United Kingdom
| | - Stuart Bevan
- Wolfson Centre for Age Related Diseases, King's College London, London, United Kingdom
- * E-mail:
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Andersson DA, Gentry C, Alenmyr L, Killander D, Lewis SE, Andersson A, Bucher B, Galzi JL, Sterner O, Bevan S, Högestätt ED, Zygmunt PM. TRPA1 mediates spinal antinociception induced by acetaminophen and the cannabinoid Δ(9)-tetrahydrocannabiorcol. Nat Commun 2011; 2:551. [PMID: 22109525 DOI: 10.1038/ncomms1559] [Citation(s) in RCA: 205] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 10/19/2011] [Indexed: 12/21/2022] Open
Abstract
TRPA1 is a unique sensor of noxious stimuli and, hence, a potential drug target for analgesics. Here we show that the antinociceptive effects of spinal and systemic administration of acetaminophen (paracetamol) are lost in Trpa1(-/-) mice. The electrophilic metabolites N-acetyl-p-benzoquinoneimine and p-benzoquinone, but not acetaminophen itself, activate mouse and human TRPA1. These metabolites also activate native TRPA1 and, as a consequence, reduce voltage-gated calcium and sodium currents in primary sensory neurons. The N-acetyl-p-benzoquinoneimine metabolite L-cysteinyl-S-acetaminophen was detected in the mouse spinal cord after systemic acetaminophen administration. In the hot-plate test, intrathecal administration of N-acetyl-p-benzoquinoneimine, p-benzoquinone and the electrophilic TRPA1 activator cinnamaldehyde produced antinociception that was lost in Trpa1(-/-) mice. Intrathecal injection of a non-electrophilic cannabinoid, Δ(9)-tetrahydrocannabiorcol, also produced TRPA1-dependent antinociception in this test. Our study provides a molecular mechanism for the antinociceptive effect of acetaminophen and discloses spinal TRPA1 activation as a potential pharmacological strategy to alleviate pain.
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Affiliation(s)
- David A Andersson
- King's College London, Wolfson Centre for Age-Related Diseases, London SE1 1UL, UK
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Graepel R, Fernandes ES, Aubdool AA, Andersson DA, Bevan S, Brain SD. 4-oxo-2-nonenal (4-ONE): evidence of transient receptor potential ankyrin 1-dependent and -independent nociceptive and vasoactive responses in vivo. J Pharmacol Exp Ther 2011; 337:117-24. [PMID: 21205926 PMCID: PMC3063740 DOI: 10.1124/jpet.110.172403] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Accepted: 12/30/2010] [Indexed: 12/22/2022] Open
Abstract
This study explores the in vivo effects of the proposed transient receptor potential ankyrin 1 (TRPA1) agonist 4-oxo-2-nonenal (4-ONE). Pharmacological inhibitors and genetically modified mice were used to investigate the ability of 4-ONE to act via TRPA1 receptors and possible mechanisms involving transient receptor potential vanilloid 1 (TRPV1). We hypothesized that 4-ONE activates sensory nerves, via TRPA1 or possibly TRPV1, and thus triggers mechanical hyperalgesia, edema formation, and vasodilatation in mice. An automated dynamic plantar aesthesiometer was used to determine hind paw withdrawal thresholds, and a laser Doppler flowmeter was used to measure skin blood flow. Edema formation was determined by measuring paw weights and thickness. 4-ONE (10 nmol) triggers unilateral mechanical hyperalgesia, edema formation, and vasodilatation in mice and is shown here to exhibit TRPA1-dependent and -independent effects. Neurogenic vasodilatation and mechanical hyperalgesia at 0.5 h postinjection were significantly greater in TRPA1 wild-type (WT) mice compared with TRPA1 knockout (KO) mice. Edema formation throughout the time course as well as mechanical hyperalgesia from 1 to 4 h postinjection were similar in WT and TRPA1 KO mice. Studies involving TRPV1 KO mice revealed no evidence of TRPV1 involvement or interactions between TRPA1 and TRPV1 in mediating the in vivo effects of 4-ONE. Previously, 4-ONE was shown to be a potent TRPA1 agonist in vitro. We demonstrate its ability to mediate vasodilatation and certain nociceptive effects in vivo. These data indicate the potential of TRPA1 as an oxidant sensor for vasodilator responses in vivo. However, 4-ONE also triggers TRPA1-independent effects that relate to edema formation and pain.
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Affiliation(s)
- Rabea Graepel
- Cardiovascular Division, King's College London, Waterloo Campus, London, United Kingdom
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Pozsgai G, Bodkin JV, Graepel R, Bevan S, Andersson DA, Brain SD. Evidence for the pathophysiological relevance of TRPA1 receptors in the cardiovascular system in vivo. Cardiovasc Res 2010; 87:760-8. [PMID: 20442136 DOI: 10.1093/cvr/cvq118] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
AIMS The aim of the study is to investigate transient receptor potential ankyrin 1 (TRPA1)-induced responses in the vasculature and on blood pressure and heart rate (HR), in response to TRPA1 agonists using wild-type (WT) and TRPA1 knockout (KO) mice. METHODS AND RESULTS TRPA1 agonists allyl isothiocyanate and cinnamaldehyde (CA) significantly increased blood flow in the skin of anaesthetized WT, but not in TRPA1 KO mice. CA also induced TRPA1-dependent relaxation of mesenteric arteries. Intravenously injected CA induced a transient hypotensive response accompanied by decreased HR that was, depending on genotype and dose, followed by a more sustained dose-dependent pressor response (10-320 micromol/kg). CA (80 micromol/kg) induced a depressor response that was significantly less in TRPA1 KO mice, with minimal pressor effects. The pressor response of a higher CA dose (320 micromol/kg) was observed in WT but not in TRPA1 KO mice, indicating involvement of TRPA1. Experiments using TRP vanilloid 1 (TRPV1) KO and calcitonin gene-related peptide (CGRP) KO mice provided little evidence for the involvement of TRPV1 or CGRP, nor did blocking substance P receptors affect responses. However, the cholinergic antagonist atropine sulphate (5 mg/kg) significantly inhibited the depressor response and slowed HR with CA (80 micromol/kg), but had no effect on pressor responses. The pressor response remained unaffected, even in the presence of the ganglion blocker hexamethonium bromide (1 mg/kg). The alpha-adrenergic blocker prazosin hydrochloride (1 mg/kg) significantly inhibited both components, but not slowed HR. CONCLUSION TRPA1 is involved in mediating vasodilation. TRPA1 can also influence changes in blood pressure of possible relevance to autonomic system reflexes and potentially to vasovagal/neurocardiogenic syncope disorders.
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Affiliation(s)
- Gabor Pozsgai
- King's College London British Heart Foundation Centre, Cardiovascular Division and Centre of Integrative Biomedicine, King's College London, Franklin-Wilkins Building, London SE1 9NH, UK
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Rainey-Smith SR, Andersson DA, Williams RJ, Rattray M. Tumour necrosis factor alpha induces rapid reduction in AMPA receptor-mediated calcium entry in motor neurones by increasing cell surface expression of the GluR2 subunit: relevance to neurodegeneration. J Neurochem 2010; 113:692-703. [DOI: 10.1111/j.1471-4159.2010.06634.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Gentry C, Stoakley N, Andersson DA, Bevan S. The roles of iPLA2, TRPM8 and TRPA1 in chemically induced cold hypersensitivity. Mol Pain 2010; 6:4. [PMID: 20092626 PMCID: PMC2822744 DOI: 10.1186/1744-8069-6-4] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Accepted: 01/21/2010] [Indexed: 12/16/2022] Open
Abstract
Background The cooling agents menthol and icilin act as agonists at TRPM8 and TRPA1. In vitro, activation of TRPM8 by icilin and cold, but not menthol, is dependent on the activity of a sub-type of phospholipase A2, iPLA2. Lysophospholipids (e.g. LPC) produced by PLA2 activity can also activate TRPM8. The role of TRPA1 as a primary cold sensor in vitro is controversial, although there is evidence that TRPA1 plays a role in behavioural responses to noxious cold stimuli. In this study, we have investigated the roles of TRPM8 and TRPA1 and the influence of iPLA2 on noxious cold sensitivities in naïve animals and after local administration of menthol, icilin and LPC. The roles of the channels in cold sensitivity were investigated in mice lacking either TRPM8 (Trpm8-/-) or TRPA1 (Trpa1-/-). Results Intraplantar administration of icilin evoked a dose-dependent increase in sensitivity to a 10°C stimulus that was inhibited by iPLA2 inhibition with BEL. In contrast the cold hypersensitivities elicited by intraplantar menthol and LPC were not inhibited by BEL treatment. BEL had no effect on basal cold sensitivity and mechanical hypersensitivities induced by the TRPV1 agonist, capsaicin, and the P2X3 agonist α,β-methylene ATP. Both Trpm8-/- and Trpa1-/- mice showed longer latencies for paw withdrawal from a 10°C stimulus than wild-type littermates. Cold hypersensitivities induced by either icilin or LPC were absent in Trpm8-/- mice but were retained in Trpa1-/- mice. In contrast, cold hypersensitivity evoked by menthol was present in Trpm8-/- mice but was lost in Trpa1-/- mice. Conclusions The findings that iPLA2 inhibition blocked the development of cold hypersensitivity after administration of icilin but failed to affect menthol-induced hypersensitivity agree well with our earlier in vitro data showing a differential effect of iPLA2 inhibition on the agonist activities of these agents. The ability of LPC to induce cold hypersensitivity supports a role for iPLA2 in modulating TRPM8 activity in vivo. Studies on genetically modified mice demonstrated that the effects of icilin and LPC were mediated by TRPM8 and not TRPA1. In contrast, menthol-induced cold hypersensitivity was dependent on expression of TRPA1 and not TRPM8.
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Affiliation(s)
- Clive Gentry
- Wolfson Centre for Age Related Diseases, King's College London, London, UK
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Andersson DA, Casillas L, Baskes MI, Lezama JS, Conradson SD. Modeling of the phase evolution in Mg1-xAlxB2 (0 < x < 0.5) and its experimental signatures. J Phys Chem B 2009; 113:11965-76. [PMID: 19673495 DOI: 10.1021/jp902505r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Despite the chemical and structural simplicity of MgB(2), at 39 K this compound has the highest known superconducting transition temperature (T(c)) of any binary compound. Electron doping by substituting Al for Mg leads to decreasing T(c), and the observed concentration dependent rate of decrease has been proposed to arise from the nonideal character of MgB(2)-AlB(2) solid solutions, which derives from the existence of an ordered Mg(0.5)Al(0.5)B(2) compound. Heterogeneous nanoscale structure patterns in solid solutions have emerged as an important concept for complex materials, ranging from actinide alloys and oxides to high-temperature cuprate superconductors and manganite-based materials exhibiting colossal magnetoresistivity. In this work we investigate the formation of structural heterogeneities in Mg(1-x)Al(x)B(2), which take the form of nanoscale Al-Al and Al-Mg domains of different geometries and sizes, using molecular statics and Monte Carlo simulations, and in particular we study the corresponding signatures in diffraction experiments. In order to undertake this task, we first derive appropriate Mg-Al-B semiempirical potentials within the modified embedded atom method formalism. These potentials are also applied to explore the equilibrium Mg(1-x)Al(x)B(2) phase diagram for 0 < x < 0.5. Additionally, density functional theory calculations were utilized to study the influence of heterogeneities on the electronic structure and charge distribution in Mg(1-x)Al(x)B(2).
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Affiliation(s)
- David A Andersson
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Bevan S, Andersson DA. TRP channel antagonists for pain--opportunities beyond TRPV1. Curr Opin Investig Drugs 2009; 10:655-663. [PMID: 19579171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
There is emerging evidence that transient receptor potential (TRP) ion channels expressed in sensory neurons are important for the transduction of chemical, thermal and mechanical signals. Increasing research efforts are directed at understanding the roles of sensory TRP channels in acute and chronic pain. Studies using RNAi techniques to reduce the levels of individual TRP channels or genetically modified mice lacking specific channels are being complemented with pharmacological studies using newly discovered investigational compounds. These studies are providing evidence that drugs that interfere with the function of TRPA1, TRPM8, TRPV4 or TRPV3 may be useful in treating pain.
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Affiliation(s)
- Stuart Bevan
- Wolfson Centre for Age Related Diseases, King's College London, Wolfson Wing, Hodgkin Building, Guy's Campus, London, SE1 1UL, UK.
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Abstract
We investigated the role of phospholipase A2 (PLA2) and the effects of PLA2 products (polyunsaturated fatty acids and lysophospholipids) on the cold-sensitive channel transient receptor potential (melastatin)-8 (TRPM8), heterologously expressed in Chinese hamster ovary cells. TRPM8 responses to cold and the agonist icilin were abolished by inhibitors of the calcium-independent (iPLA2) form of the enzyme, whereas responses to menthol were less sensitive to iPLA2 inhibition. Inhibition of PLA2 similarly abolished the cold responses of the majority of cold-sensitive dorsal root ganglion neurons. The products of PLA2 had opposing effects on TRPM8. Lysophospholipids (LPLs) (lysophosphatidylcholine, lysophosphatidylinositol, and lysophosphatidylserine) altered the thermal sensitivity of TRPM8, raising the temperature threshold toward normal body temperature. Polyunsaturated fatty acids (PUFAs), such as arachidonic acid, inhibited the activation of TRPM8 by cold, icilin, and menthol. The relative potencies of lysophospholipids and PUFAs are such that lysophosphatidylcholine is able to modulate TRPM8 in the presence of an equimolar concentration of arachidonic acid. Positive modulation by LPLs provides a potential physiological mechanism for sensitizing and activating TRPM8 in the absence of temperature variations.
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Affiliation(s)
- David A Andersson
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom.
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Abstract
Oxides with the cubic fluorite structure, e.g., ceria (CeO2), are known to be good solid electrolytes when they are doped with cations of lower valence than the host cations. The high ionic conductivity of doped ceria makes it an attractive electrolyte for solid oxide fuel cells, whose prospects as an environmentally friendly power source are very promising. In these electrolytes, the current is carried by oxygen ions that are transported by oxygen vacancies, present to compensate for the lower charge of the dopant cations. Ionic conductivity in ceria is closely related to oxygen-vacancy formation and migration properties. A clear physical picture of the connection between the choice of a dopant and the improvement of ionic conductivity in ceria is still lacking. Here we present a quantum-mechanical first-principles study of the influence of different trivalent impurities on these properties. Our results reveal a remarkable correspondence between vacancy properties at the atomic level and the macroscopic ionic conductivity. The key parameters comprise migration barriers for bulk diffusion and vacancy-dopant interactions, represented by association (binding) energies of vacancy-dopant clusters. The interactions can be divided into repulsive elastic and attractive electronic parts. In the optimal electrolyte, these parts should balance. This finding offers a simple and clear way to narrow the search for superior dopants and combinations of dopants. The ideal dopant should have an effective atomic number between 61 (Pm) and 62 (Sm), and we elaborate that combinations of Nd/Sm and Pr/Gd show enhanced ionic conductivity, as compared with that for each element separately.
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Affiliation(s)
- David A Andersson
- Applied Materials Physics, Department of Materials Science and Engineering, Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
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Högestätt ED, Jönsson BAG, Ermund A, Andersson DA, Björk H, Alexander JP, Cravatt BF, Basbaum AI, Zygmunt PM. Conversion of acetaminophen to the bioactive N-acylphenolamine AM404 via fatty acid amide hydrolase-dependent arachidonic acid conjugation in the nervous system. J Biol Chem 2005; 280:31405-12. [PMID: 15987694 DOI: 10.1074/jbc.m501489200] [Citation(s) in RCA: 281] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Acetaminophen (paracetamol) is a popular domestic analgesic and antipyretic agent with a weak anti-inflammatory action and a low incidence of adverse effects as compared with aspirin and other non-steroidal anti-inflammatory drugs. Here we show that acetaminophen, following deacetylation to its primary amine, is conjugated with arachidonic acid in the brain and the spinal cord to form the potent TRPV1 agonist N-arachidonoylphenolamine (AM404). This conjugation is absent in mice lacking the enzyme fatty acid amide hydrolase. AM404 also inhibits purified cyclooxygenase (COX)-1 and COX-2 and prostaglandin synthesis in lipopolysaccharide-stimulated RAW264.7 macrophages. This novel metabolite of acetaminophen also acts on the endogenous cannabinoid system, which, together with TRPV1 and COX, is present in the pain and thermoregulatory pathways. These findings identify fatty acid conjugation as a novel pathway for drug metabolism and provide a molecular mechanism for the occurrence of the analgesic N-acylphenolamine AM404 in the nervous system following treatment with acetaminophen.
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Affiliation(s)
- Edward D Högestätt
- Division of Clinical Chemistry and Pharmacology, Department of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden
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Abstract
TRPM8 is a nonselective cation channel activated by cold and the cooling compounds menthol and icilin (Peier et al., 2002). Here, we have used electrophysiology and the calcium-sensitive dye Fura-2 to study the effect of pH and interactions between temperature, pH, and the two chemical agonists menthol and icilin on TRPM8 expressed in Chinese hamster ovary cells. Menthol, icilin, and cold all evoked stimulus-dependent [Ca2+]i responses in standard physiological solutions of pH 7.3. Increasing the extracellular [H+] from pH 7.3 to approximately pH 6 abolished responses to icilin and cold stimulation but did not affect responses to menthol. Icilin concentration-response curves were significantly shifted to the right when pH was lowered from 7.3 to 6.9, whereas those with menthol were unaltered in solutions of pH 6.1. When cells were exposed to solutions in the range of pH 8.1-6.5, the temperature threshold for activation was elevated at higher pH and depressed at lower pH. Superfusing cells with a low subactivating concentration of icilin or menthol elevated the threshold for cold activation at pH 7.4, but cooling failed to evoke [Ca2+]i responses at pH 6 in the presence of either agonist. In voltage-clamp experiments in which the intracellular pH was buffered to different levels, acidification reduced the current amplitude of icilin responses and shifted the threshold for cold activation to lower values with half-maximal inhibition at pH 7.2 and pH 7.6. The results demonstrate that the activation of TRPM8 by icilin and cold, but not menthol, is modulated by intracellular pH in the physiological range. Furthermore, our data suggest that activation by icilin and cold involve a different mechanism to activation by menthol.
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Affiliation(s)
- David A Andersson
- Novartis Institute for Medical Sciences, London WC1E 6BN, United Kingdom.
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Korzhavyi PA, Vitos L, Andersson DA, Johansson B. Oxidation of plutonium dioxide. Nat Mater 2004; 3:225-228. [PMID: 15034561 DOI: 10.1038/nmat1095] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2003] [Accepted: 02/13/2004] [Indexed: 05/24/2023]
Abstract
The physics and chemistry of the actinide elements form the scientific basis for rational handling of nuclear materials. In recent experiments, most unexpectedly, plutonium dioxide has been found to react with water to form higher oxides up to PuO(2.27), whereas PuO(2) had always been thought to be the highest stable oxide of plutonium. We perform a theoretical analysis of this complicated situation on the basis of total energies calculated within density functional theory combined with well-established thermodynamic data. The reactions of PuO(2) with either O(2) or H(2)O to form PuO(2+delta) are calculated to be endothermic: that is, in order to occur they require a supply of energy. However, our calculations show that PuO(2+delta) can be formed, as an intermediate product, by reactions with the products of radiolysis of water, such as H(2)O(2).
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Affiliation(s)
- Pavel A Korzhavyi
- Applied Materials Physics, Department of Materials Science and Engineering, Royal Institute of Technology (KTH), SE-100 44 Stockholm, Sweden.
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Story GM, Peier AM, Reeve AJ, Eid SR, Mosbacher J, Hricik TR, Earley TJ, Hergarden AC, Andersson DA, Hwang SW, McIntyre P, Jegla T, Bevan S, Patapoutian A. ANKTM1, a TRP-like channel expressed in nociceptive neurons, is activated by cold temperatures. Cell 2003; 112:819-29. [PMID: 12654248 DOI: 10.1016/s0092-8674(03)00158-2] [Citation(s) in RCA: 1854] [Impact Index Per Article: 88.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Mammals detect temperature with specialized neurons in the peripheral nervous system. Four TRPV-class channels have been implicated in sensing heat, and one TRPM-class channel in sensing cold. The combined range of temperatures that activate these channels covers a majority of the relevant physiological spectrum sensed by most mammals, with a significant gap in the noxious cold range. Here, we describe the characterization of ANKTM1, a cold-activated channel with a lower activation temperature compared to the cold and menthol receptor, TRPM8. ANKTM1 is a distant family member of TRP channels with very little amino acid similarity to TRPM8. It is found in a subset of nociceptive sensory neurons where it is coexpressed with TRPV1/VR1 (the capsaicin/heat receptor) but not TRPM8. Consistent with the expression of ANKTM1, we identify noxious cold-sensitive sensory neurons that also respond to capsaicin but not to menthol.
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Affiliation(s)
- Gina M Story
- Department of Cell Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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Andersson DA, Adner M, Högestätt ED, Zygmunt PM. Mechanisms underlying tissue selectivity of anandamide and other vanilloid receptor agonists. Mol Pharmacol 2002; 62:705-13. [PMID: 12181448 DOI: 10.1124/mol.62.3.705] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Anandamide acts as a full vanilloid receptor agonist in many bioassay systems, but it is a weak activator of primary afferents in the airways. To address this discrepancy, we compared the effect of different vanilloid receptor agonists in isolated airways and mesenteric arteries of guinea pig using preparations containing different phenotypes of the capsaicin-sensitive sensory nerve. We found that anandamide is a powerful vasodilator of mesenteric arteries but a weak constrictor of main bronchi. These effects of anandamide are mediated by vanilloid receptors on primary afferents and do not involve cannabinoid receptors. Anandamide also contracts isolated lung strips, an effect caused by the hydrolysis of anandamide and subsequent formation of cyclooxygenase products. Although capsaicin is equally potent in bronchi and mesenteric arteries, anandamide, resiniferatoxin, and particularly olvanil are significantly less potent in bronchi. Competition experiments with the vanilloid receptor antagonist capsazepine did not provide evidence of vanilloid receptor heterogeneity. Arachidonoyl-5-methoxytryptamine (VDM13), an inhibitor of the anandamide membrane transporter, attenuates responses to olvanil and anandamide, but not capsaicin and resiniferatoxin, in mesenteric arteries. VDM13 did not affect responses to these agonists in bronchi, suggesting that the anandamide membrane transporter is absent in this phenotype of the sensory nerve. Computer simulations using an operational model of agonism were consistent, with differences in intrinsic efficacy and receptor content being responsible for the remaining differences in agonist potency between the tissues. This study describes differences between vanilloid receptor agonists regarding tissue selectivity and provides a conceptual framework for developing tissue-selective vanilloid receptor agonists devoid of bronchoconstrictor activity.
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Affiliation(s)
- David A Andersson
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University Hospital, Lund University, Lund, Sweden
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Peier AM, Reeve AJ, Andersson DA, Moqrich A, Earley TJ, Hergarden AC, Story GM, Colley S, Hogenesch JB, McIntyre P, Bevan S, Patapoutian A. A heat-sensitive TRP channel expressed in keratinocytes. Science 2002; 296:2046-9. [PMID: 12016205 DOI: 10.1126/science.1073140] [Citation(s) in RCA: 650] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Mechanical and thermal cues stimulate a specialized group of sensory neurons that terminate in the skin. Three members of the transient receptor potential (TRP) family of channels are expressed in subsets of these neurons and are activated at distinct physiological temperatures. Here, we describe the cloning and characterization of a novel thermosensitive TRP channel. TRPV3 has a unique threshold: It is activated at innocuous (warm) temperatures and shows an increased response at noxious temperatures. TRPV3 is specifically expressed in keratinocytes; hence, skin cells are capable of detecting heat via molecules similar to those in heat-sensing neurons.
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Affiliation(s)
- Andrea M Peier
- Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121, USA
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Peier AM, Moqrich A, Hergarden AC, Reeve AJ, Andersson DA, Story GM, Earley TJ, Dragoni I, McIntyre P, Bevan S, Patapoutian A. A TRP channel that senses cold stimuli and menthol. Cell 2002; 108:705-15. [PMID: 11893340 DOI: 10.1016/s0092-8674(02)00652-9] [Citation(s) in RCA: 1631] [Impact Index Per Article: 74.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A distinct subset of sensory neurons are thought to directly sense changes in thermal energy through their termini in the skin. Very little is known about the molecules that mediate thermoreception by these neurons. Vanilloid Receptor 1 (VR1), a member of the TRP family of channels, is activated by noxious heat. Here we describe the cloning and characterization of TRPM8, a distant relative of VR1. TRPM8 is specifically expressed in a subset of pain- and temperature-sensing neurons. Cells overexpressing the TRPM8 channel can be activated by cold temperatures and by a cooling agent, menthol. Our identification of a cold-sensing TRP channel in a distinct subpopulation of sensory neurons implicates an expanded role for this family of ion channels in somatic sensory detection.
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Affiliation(s)
- Andrea M Peier
- Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121, USA
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Högestätt ED, Johansson R, Andersson DA, Zygmunt PM. Involvement of sensory nerves in vasodilator responses to acetylcholine and potassium ions in rat hepatic artery. Br J Pharmacol 2000; 130:27-32. [PMID: 10780994 PMCID: PMC1572030 DOI: 10.1038/sj.bjp.0703258] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
In the presence of ouabain (1 mM), acetylcholine and KCl (5 mM) evoked endothelium-independent relaxations in rat hepatic arteries. Treatment with capsaicin (10 microM), scopolamine (1 microM) or CGRP(8 - 37) (3 microM) prevented these relaxations. Acetylcholine-induced relaxations in intact arterial segments in the presence of indomethacin (10 microM) and N(G)-nitro-L-arginine (0.3 mM) were only partially inhibited by ouabain plus BaCl(2) (30 microM). However, ouabain plus BaCl(2) almost abolished such relaxations in capsaicin-pre-treated preparations. In arteries without endothelium, the neurosecretagogue alpha-latrotoxin (1 nM) induced complete relaxations, which were abolished by CGRP(8 - 37) or pre-treatment with capsaicin. alpha-Latrotoxin also induced a smooth muscle hyperpolarization (12+/-2 mV), which was abolished by CGRP(8 - 37). The ability of ouabain to disclose a CGRP-mediated neurogenic relaxation must be considered when this agent is used as a pharmacological tool. The results further suggest that CGRP is a nerve-derived hyperpolarizing factor in the rat hepatic artery.
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Affiliation(s)
- E D Högestätt
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden.
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Andersson DA, Zygmunt PM, Movahed P, Andersson TLG, Högestätt ED. Effects of inhibitors of small- and intermediate-conductance calcium-activated potassium channels, inwardly-rectifying potassium channels and Na(+)/K(+) ATPase on EDHF relaxations in the rat hepatic artery. Br J Pharmacol 2000; 129:1490-6. [PMID: 10742306 PMCID: PMC1571979 DOI: 10.1038/sj.bjp.0703226] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. In the rat hepatic artery, the SK(Ca) inhibitors UCL 1684 (300 nM) completely blocked, and scyllatoxin (1 microM) and d-tubocurarine (100 microM) partially inhibited EDHF relaxations when each of them was combined with charybdotoxin (300 nM). 2. The IK(Ca) inhibitors clotrimazole (3 microM) and 2-chlorophenyl-bisphenyl-methanol (3 microM) strongly depressed EDHF relaxations when each of them was combined with apamin (300 nM). The cytochrome P450 mono-oxygenase inhibitor ketoconazole (10 microM) had no effect in the presence of apamin. 3. Ciclazindol (10 microM), which abolishes EDHF relaxations in the presence of apamin, almost completely prevented the calcium ionophore (A23187) stimulated (86)Rb(+) influx via the Gardos channel (IK(Ca)) in human erythrocytes. 4. The Na(+)/K(+) ATPase inhibitor ouabain (500 microM) and the K(IR) blocker Ba(2+) (30 microM) neither alone nor in combination inhibited EDHF relaxations. Ba(2+) was also without effect in the presence of either apamin or charybdotoxin. 5. In contrast to EDHF, an increase in extracellular [K(+)] from 4.6 mM to 9.6, 14.6 and 19.6 mM inconsistently relaxed arteries. In K(+)-free physiological salt solution, re-admission of K(+) always caused complete and sustained relaxations which were abolished by ouabain but unaffected by Ba(2+). 6. The present study provides pharmacological evidence for the involvement of SK(Ca) and IK(Ca) in the action of EDHF in the rat hepatic artery. Our results are not consistent with the idea that EDHF is K(+) activating Na(+)/K(+) ATPase and K(IR) in this blood vessel.
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Affiliation(s)
- David A Andersson
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden
| | - Peter M Zygmunt
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden
- Author for correspondence:
| | - Pouya Movahed
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden
| | - Tomas L G Andersson
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden
| | - Edward D Högestätt
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, Lund University, SE-221 85 Lund, Sweden
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Zygmunt PM, Petersson J, Andersson DA, Chuang H, Sørgård M, Di Marzo V, Julius D, Högestätt ED. Vanilloid receptors on sensory nerves mediate the vasodilator action of anandamide. Nature 1999; 400:452-7. [PMID: 10440374 DOI: 10.1038/22761] [Citation(s) in RCA: 1646] [Impact Index Per Article: 65.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The endogenous cannabinoid receptor agonist anandamide is a powerful vasodilator of isolated vascular preparations, but its mechanism of action is unclear. Here we show that the vasodilator response to anandamide in isolated arteries is capsaicin-sensitive and accompanied by release of calcitonin-gene-related peptide (CGRP). The selective CGRP-receptor antagonist 8-37 CGRP, but not the cannabinoid CB1 receptor blocker SR141716A, inhibited the vasodilator effect of anandamide. Other endogenous (2-arachidonylglycerol, palmitylethanolamide) and synthetic (HU 210, WIN 55,212-2, CP 55,940) CB1 and CB2 receptor agonists could not mimic the action of anandamide. The selective 'vanilloid receptor' antagonist capsazepine inhibited anandamide-induced vasodilation and release of CGRP. In patch-clamp experiments on cells expressing the cloned vanilloid receptor (VR1), anandamide induced a capsazepine-sensitive current in whole cells and isolated membrane patches. Our results indicate that anandamide induces vasodilation by activating vanilloid receptors on perivascular sensory nerves and causing release of CGRP. The vanilloid receptor may thus be another molecular target for endogenous anandamide, besides cannabinoid receptors, in the nervous and cardiovascular systems.
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MESH Headings
- Animals
- Arachidonic Acids/antagonists & inhibitors
- Arachidonic Acids/metabolism
- Arachidonic Acids/pharmacology
- Basilar Artery/drug effects
- Basilar Artery/innervation
- Calcitonin Gene-Related Peptide/metabolism
- Calcitonin Gene-Related Peptide/pharmacology
- Calcitonin Gene-Related Peptide Receptor Antagonists
- Calcium Channels/metabolism
- Capsaicin/analogs & derivatives
- Capsaicin/pharmacology
- Cell Line
- Endocannabinoids
- Female
- Guinea Pigs
- Hepatic Artery/drug effects
- Hepatic Artery/innervation
- In Vitro Techniques
- Neurons, Afferent/drug effects
- Neurons, Afferent/metabolism
- Peptide Fragments/pharmacology
- Polyunsaturated Alkamides
- Rats
- Rats, Wistar
- Receptor, Cannabinoid, CB2
- Receptors, Cannabinoid
- Receptors, Drug/agonists
- Receptors, Drug/antagonists & inhibitors
- Receptors, Drug/genetics
- Receptors, Drug/metabolism
- Recombinant Proteins/metabolism
- Vasodilator Agents/antagonists & inhibitors
- Vasodilator Agents/metabolism
- Vasodilator Agents/pharmacology
- Xenopus
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Affiliation(s)
- P M Zygmunt
- Department of Clinical Pharmacology, Institute of Laboratory Medicine, University of Lund, Sweden
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