1
|
Kim YJ, Foodoul MA, Parry JA, Mauffrey C. Surgical approach of T-type acetabular fractures does not affect quality of reduction on postoperative CT or the likelihood of postoperative complications. Injury 2023:S0020-1383(23)00293-0. [PMID: 37059600 DOI: 10.1016/j.injury.2023.03.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/06/2023] [Accepted: 03/28/2023] [Indexed: 04/16/2023]
Abstract
INTRODUCTION T-type acetabular fractures are rare but challenging injuries. The purpose of this study was to evaluate for associations between chosen surgical approach for T-type acetabular fracture fixation, reduction quality, and complications. METHODS Retrospective, single institution study of T-type acetabular fractures who underwent surgical fixation. Surgical interventions included open reduction and internal fixation (ORIF) through an anterior intrapelvic approach (AIP) (modified Rives-Stoppa) and/or posterior (Kocher-Langenbeck [KL]), or percutaneous screw fixation. The primary outcome was reduction quality on routine postoperative computed tomography (CT) scan and postoperative complications. RESULTS During the study period (March 2016 - October 2022), 22 patients presented with T-type acetabular fractures. Surgical approaches included AIP [31.8% (7/22)], percutaneous [27.3% (6/22)], AIP+KL [22.7% (5/22)], and KL [18.2% (4/22)]. On CT scans, 9.0% (2/22) had anatomic reductions, 27.2% (6/22) had fair reductions, and 63.6% (14/22) had poor reductions based on Matta Reduction Criteria. There was no observed difference in reduction quality between surgical approaches. Poor reductions (> 3 mm) were not associated with surgical approach, fracture classification, unstable pelvic ring injuries, posterior wall fractures, T-stem component, transverse component, preoperative articular displacement, preoperative femoral head protrusion, or surgeon experience. Complications occurred in 50.0% (11/22) of patients. No observed difference in complication rates was noted between the surgical approaches. CONCLUSION T-type acetabular fractures are challenging injuries with few patients achieving anatomic reduction on postoperative CT scans and half of patients developing complications.
Collapse
Affiliation(s)
- Ye Joon Kim
- Department of Orthopedics, Denver Health Medical Center, Denver, CO, USA
| | | | - Joshua A Parry
- Department of Orthopedics, Denver Health Medical Center, Denver, CO, USA; Department of Orthopedics, University of Colorado, Aurora, CO, USA
| | - Cyril Mauffrey
- Department of Orthopedics, Denver Health Medical Center, Denver, CO, USA; Department of Orthopedics, University of Colorado, Aurora, CO, USA.
| |
Collapse
|
2
|
Duran P, Loya-López S, Ran D, Tang C, Calderon-Rivera A, Gomez K, Stratton HJ, Huang S, Xu YM, Wijeratne EMK, Perez-Miller S, Shan Z, Cai S, Gabrielsen AT, Dorame A, Masterson KA, Alsbiei O, Madura CL, Luo G, Moutal A, Streicher J, Zamponi GW, Gunatilaka AAL, Khanna R. The natural product argentatin C attenuates postoperative pain via inhibition of voltage-gated sodium and T-type voltage-gated calcium channels. Br J Pharmacol 2022; 180:1267-1285. [PMID: 36245395 DOI: 10.1111/bph.15974] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 07/07/2022] [Accepted: 07/15/2022] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND AND PURPOSE Postoperative pain occurs in as many as 70% of surgeries performed worldwide. Postoperative pain management still relies on opioids despite their negative consequences, resulting in a public health crisis. Therefore, it is important to develop alternative therapies to treat chronic pain. Natural products derived from medicinal plants are potential sources of novel biologically active compounds for development of safe analgesics. In this study, we screened a library of natural products to identify small molecules that target the activity of voltage-gated sodium and calcium channels that have important roles in nociceptive sensory processing. EXPERIMENTAL APPROACH Fractions derived from the Native American medicinal plant, Parthenium incanum, were assessed using depolarization-evoked calcium influx in rat dorsal root ganglion (DRG) neurons. Further separation of these fractions yielded a cycloartane-type triterpene identified as argentatin C, which was additionally evaluated using whole-cell voltage and current-clamp electrophysiology, and behavioural analysis in a mouse model of postsurgical pain. KEY RESULTS Argentatin C blocked the activity of both voltage-gated sodium and low-voltage-activated (LVA) calcium channels in calcium imaging assays. Docking analysis predicted that argentatin C may bind to NaV 1.7-1.9 and CaV 3.1-3.3 channels. Furthermore, argentatin C decreased Na+ and T-type Ca2+ currents as well as excitability in rat and macaque DRG neurons, and reversed mechanical allodynia in a mouse model of postsurgical pain. CONCLUSION AND IMPLICATIONS These results suggest that the dual effect of argentatin C on voltage-gated sodium and calcium channels supports its potential as a novel treatment for painful conditions.
Collapse
Affiliation(s)
- Paz Duran
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA
| | - Santiago Loya-López
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA
| | - Dongzhi Ran
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Cheng Tang
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA.,NYU Pain Research Center, New York, New York, USA.,Department of Biochemistry and Molecular Biology, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Aida Calderon-Rivera
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA
| | - Kimberly Gomez
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA
| | - Harrison J Stratton
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Sun Huang
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Ya-Ming Xu
- Southwest Center for Natural Products Research, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, The University of Arizona, Tucson, Arizona, USA
| | - E M Kithsiri Wijeratne
- Southwest Center for Natural Products Research, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, The University of Arizona, Tucson, Arizona, USA
| | - Samantha Perez-Miller
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA
| | - Zhiming Shan
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Song Cai
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Anna T Gabrielsen
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Angie Dorame
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Kyleigh A Masterson
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Omar Alsbiei
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Cynthia L Madura
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Guoqin Luo
- Southwest Center for Natural Products Research, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, The University of Arizona, Tucson, Arizona, USA
| | - Aubin Moutal
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - John Streicher
- Department of Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - A A Leslie Gunatilaka
- Southwest Center for Natural Products Research, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, The University of Arizona, Tucson, Arizona, USA
| | - Rajesh Khanna
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, New York, USA.,NYU Pain Research Center, New York, New York, USA
| |
Collapse
|
3
|
Papazoglou A, Arshaad MI, Henseler C, Daubner J, Broich K, Hescheler J, Ehninger D, Haenisch B, Weiergräber M. Ca v3 T-Type Voltage-Gated Ca 2+ Channels and the Amyloidogenic Environment: Pathophysiology and Implications on Pharmacotherapy and Pharmacovigilance. Int J Mol Sci 2022; 23:ijms23073457. [PMID: 35408817 PMCID: PMC8998330 DOI: 10.3390/ijms23073457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 12/07/2022] Open
Abstract
Voltage-gated Ca2+ channels (VGCCs) were reported to play a crucial role in neurotransmitter release, dendritic resonance phenomena and integration, and the regulation of gene expression. In the septohippocampal system, high- and low-voltage-activated (HVA, LVA) Ca2+ channels were shown to be involved in theta genesis, learning, and memory processes. In particular, HVA Cav2.3 R-type and LVA Cav3 T-type Ca2+ channels are expressed in the medial septum-diagonal band of Broca (MS-DBB), hippocampal interneurons, and pyramidal cells, and ablation of both channels was proven to severely modulate theta activity. Importantly, Cav3 Ca2+ channels contribute to rebound burst firing in septal interneurons. Consequently, functional impairment of T-type Ca2+ channels, e.g., in null mutant mouse models, caused tonic disinhibition of the septohippocampal pathway and subsequent enhancement of hippocampal theta activity. In addition, impairment of GABA A/B receptor transcription, trafficking, and membrane translocation was observed within the septohippocampal system. Given the recent findings that amyloid precursor protein (APP) forms complexes with GABA B receptors (GBRs), it is hypothesized that T-type Ca2+ current reduction, decrease in GABA receptors, and APP destabilization generate complex functional interdependence that can constitute a sophisticated proamyloidogenic environment, which could be of potential relevance in the etiopathogenesis of Alzheimer’s disease (AD). The age-related downregulation of T-type Ca2+ channels in humans goes together with increased Aβ levels that could further inhibit T-type channels and aggravate the proamyloidogenic environment. The mechanistic model presented here sheds new light on recent reports about the potential risks of T-type Ca2+ channel blockers (CCBs) in dementia, as observed upon antiepileptic drug application in the elderly.
Collapse
Affiliation(s)
- Anna Papazoglou
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (A.P.); (M.I.A.); (C.H.); (J.D.)
| | - Muhammad Imran Arshaad
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (A.P.); (M.I.A.); (C.H.); (J.D.)
| | - Christina Henseler
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (A.P.); (M.I.A.); (C.H.); (J.D.)
| | - Johanna Daubner
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (A.P.); (M.I.A.); (C.H.); (J.D.)
| | - Karl Broich
- Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (K.B.); (B.H.)
| | - Jürgen Hescheler
- Faculty of Medicine, Institute of Neurophysiology, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany;
- Center of Physiology and Pathophysiology, Faculty of Medicine, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
| | - Dan Ehninger
- Translational Biogerontology, German Center for Neurodegenerative Diseases (Deutsches Zentrum für Neurodegenerative Erkrankungen, DZNE), Venusberg-Campus 1/99, 53127 Bonn, Germany;
- German Center for Neurodegenerative Diseases (Deutsches Zentrum für Neurodegenerative Erkrankungen, DZNE), Venusberg-Campus 1/99, 53127 Bonn, Germany
| | - Britta Haenisch
- Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (K.B.); (B.H.)
- German Center for Neurodegenerative Diseases (Deutsches Zentrum für Neurodegenerative Erkrankungen, DZNE), Venusberg-Campus 1/99, 53127 Bonn, Germany
- Center for Translational Medicine, Medical Faculty, University of Bonn, 53113 Bonn, Germany
| | - Marco Weiergräber
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (A.P.); (M.I.A.); (C.H.); (J.D.)
- Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany; (K.B.); (B.H.)
- Faculty of Medicine, Institute of Neurophysiology, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany;
- Center of Physiology and Pathophysiology, Faculty of Medicine, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
- Correspondence: ; Tel.: +49-228-99307-4358
| |
Collapse
|
4
|
Garcia-Caballero A, Gadotti VM, Ali MY, Bladen C, Gambeta E, Van Humbeck JF, MacCallum JL, Zamponi GW. A Synthetically Accessible Small-Molecule Inhibitor of USP5-Cav3.2 Calcium Channel Interactions with Analgesic Properties. ACS Chem Neurosci 2022; 13:524-536. [PMID: 35113527 DOI: 10.1021/acschemneuro.1c00765] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Cav3.2 calcium channels are important mediators of nociceptive signaling in the primary afferent pain pathway, and their expression is increased in various rodent models of chronic pain. Previous work from our laboratory has shown that this is in part mediated by an aberrant expression of deubiquitinase USP5, which associates with these channels and increases their stability. Here, we report on a novel bioactive rhodanine compound (II-1), which was identified in compound library screens. II-1 inhibits biochemical interactions between USP5 and the Cav3.2 domain III-IV linker in a dose-dependent manner, without affecting the enzymatic activity of USP5. Molecular docking analysis reveals two potential binding pockets at the USP5-Cav3.2 interface that are distinct from the binding site of the deubiquitinase inhibitor WP1130 (a.k.a. degrasyn). With an understanding of the ability of some rhodanines to produce false positives in high-throughput screening, we have conducted several orthogonal assays to confirm the validity of this hit, including in vivo experiments. Intrathecal delivery of II-1 inhibited both phases of formalin-induced nocifensive behaviors in mice, as well as abolished thermal hyperalgesia induced by the delivery of complete Freund's adjuvant (CFA) to the hind paw. The latter effects were abolished in Cav3.2 null mice, thus confirming that Cav3.2 is required for the action of II-1. II-1 also mediated a robust inhibition of mechanical allodynia induced by injury to the sciatic nerve. Altogether, our data uncover a novel class of analgesics─well suited to rapid structure-activity relationship studies─that target the Cav3.2/USP5 interface.
Collapse
Affiliation(s)
- Agustin Garcia-Caballero
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary T2N 4N1, Canada
- Zymedyne Therapeutics, Calgary T2L 1Y8, Canada
| | - Vinicius M. Gadotti
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary T2N 4N1, Canada
- Zymedyne Therapeutics, Calgary T2L 1Y8, Canada
| | - Md Yousof Ali
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary T2N 4N1, Canada
| | - Chris Bladen
- Zymedyne Therapeutics, Calgary T2L 1Y8, Canada
- Faculty of Medicine, Macquarie University, 75 Talavera Rd, Sydney, New South Wales 2109, Australia
| | - Eder Gambeta
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary T2N 4N1, Canada
| | | | | | - Gerald W. Zamponi
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary T2N 4N1, Canada
- Zymedyne Therapeutics, Calgary T2L 1Y8, Canada
| |
Collapse
|
5
|
Gadotti VM, Huang S, Zamponi GW. The terpenes camphene and alpha-bisabolol inhibit inflammatory and neuropathic pain via Cav3.2 T-type calcium channels. Mol Brain 2021; 14:166. [PMID: 34775970 PMCID: PMC8591808 DOI: 10.1186/s13041-021-00876-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/03/2021] [Indexed: 11/10/2022] Open
Abstract
T-type calcium channels are known molecular targets of certain phytocannabinoids and endocannabinoids. Here we explored the modulation of Cav3.2 T-type calcium channels by terpenes derived from cannabis plants. A screen of eight commercially available terpenes revealed that camphene and alpha-bisabolol mediated partial, but significant inhibition of Cav3.2 channels expressed in tsA-201 cells, as well as native T-type channels in mouse dorsal root ganglion neurons. Both compounds inhibited peak current amplitude with IC50s in the low micromolar range, and mediated an additional small hyperpolarizing shift in half-inactivation voltage. When delivered intrathecally, both terpenes inhibited nocifensive responses in mice that had received an intraplantar injection of formalin, with alpha-bisabolol showing greater efficacy. Both terpenes reduced thermal hyperalgesia in mice injected with Complete Freund's adjuvant. This effect was independent of sex, and absent in Cav3.2 null mice, indicating that these compounds mediate their analgesic properties by acting on Cav3.2 channels. Both compounds also inhibited mechanical hypersensitivity in a mouse model of neuropathic pain. Hence, camphene and alpha-bisabolol have a wide spectrum of analgesic action by virtue of inhibiting Cav3.2 T-type calcium channels.
Collapse
Affiliation(s)
- Vinicius M Gadotti
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, AB, T2N 4N1, Calgary, Canada
| | - Sun Huang
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, AB, T2N 4N1, Calgary, Canada
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, University of Calgary, AB, T2N 4N1, Calgary, Canada.
| |
Collapse
|
6
|
Fernandez FR, Iftinca MC, Zamponi GW, Turner RW. Modeling temperature- and Cav3 subtype-dependent alterations in T-type calcium channel mediated burst firing. Mol Brain 2021; 14:115. [PMID: 34274007 PMCID: PMC8285791 DOI: 10.1186/s13041-021-00813-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/18/2021] [Indexed: 11/10/2022] Open
Abstract
T-type calcium channels are important regulators of neuronal excitability. The mammalian brain expresses three T-type channel isoforms (Cav3.1, Cav3.2 and Cav3.3) with distinct biophysical properties that are critically regulated by temperature. Here, we test the effects of how temperature affects spike output in a reduced firing neuron model expressing specific Cav3 channel isoforms. The modeling data revealed only a minimal effect on baseline spontaneous firing near rest, but a dramatic increase in rebound burst discharge frequency for Cav3.1 compared to Cav3.2 or Cav3.3 due to differences in window current or activation/recovery time constants. The reduced response by Cav3.2 could optimize its activity where it is expressed in peripheral tissues more subject to temperature variations than Cav3.1 or Cav3.3 channels expressed prominently in the brain. These tests thus reveal that aspects of neuronal firing behavior are critically dependent on both temperature and T-type calcium channel subtype.
Collapse
Affiliation(s)
| | - Mircea C Iftinca
- Department of Physiology and Pharmacology, Cumming School of Medicine University of Calgary, Calgary, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Cumming School of Medicine University of Calgary, Calgary, Canada. .,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada. .,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada.
| | - Ray W Turner
- Department of Cell Biology and Anatomy, Cumming School of Medicine University of Calgary, Calgary, Canada. .,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada. .,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada.
| |
Collapse
|
7
|
Abstract
Calcium signaling in vascular smooth muscle is crucial for arterial tone regulation and vascular function. Several proteins, including Ca2+ channels, function in an orchestrated fashion so that blood vessels can sense and respond to physiological stimuli such as changes in intravascular pressure. Activation of the voltage-dependent Ca2+ channel, Cav1.2, leads to Ca2+ influx and consequently arterial tone development and vasoconstriction. Unique among Ca2+ channels, the vascular Cav3.2 T-type channel mediates feedback inhibition of arterial tone-and therefore causes vasodilation-of resistance arteries by virtue of functional association with hyperpolarizing ion channels. During aging, several signaling modalities are altered along with vascular remodeling. There is a growing appreciation of how calcium channel signaling alters with aging and how this may affect vascular function. Here, we discuss key determinants of arterial tone development and the crucial involvement of Ca2+ channels. We next provide an updated view of key changes in Ca2+ channel expression and function during aging and how these affect vascular function. Further, this article synthesizes new questions in light of recent developments. We hope that these questions will outline a roadmap for new research, which, undoubtedly, will unravel a more comprehensive picture of arterial tone dysfunction during aging.
Collapse
Affiliation(s)
- Osama F. Harraz
- Dept. of Pharmacology, Larner College of Medicine, University of Vermont, Burlington, VT, 05405 USA,Corresponding author. (O.F. Harraz)
| | - Lars Jørn Jensen
- Pathobiological Sciences, Dept. of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg C, Denmark
| |
Collapse
|
8
|
Lory P, Nicole S, Monteil A. Neuronal Cav3 channelopathies: recent progress and perspectives. Pflugers Arch 2020; 472:831-844. [PMID: 32638069 PMCID: PMC7351805 DOI: 10.1007/s00424-020-02429-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [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: 06/08/2020] [Revised: 06/08/2020] [Accepted: 06/26/2020] [Indexed: 12/22/2022]
Abstract
T-type, low-voltage activated, calcium channels, now designated Cav3 channels, are involved in a wide variety of physiological functions, especially in nervous systems. Their unique electrophysiological properties allow them to finely regulate neuronal excitability and to contribute to sensory processing, sleep, and hormone and neurotransmitter release. In the last two decades, genetic studies, including exploration of knock-out mouse models, have greatly contributed to elucidate the role of Cav3 channels in normal physiology, their regulation, and their implication in diseases. Mutations in genes encoding Cav3 channels (CACNA1G, CACNA1H, and CACNA1I) have been linked to a variety of neurodevelopmental, neurological, and psychiatric diseases designated here as neuronal Cav3 channelopathies. In this review, we describe and discuss the clinical findings and supporting in vitro and in vivo studies of the mutant channels, with a focus on de novo, gain-of-function missense mutations recently discovered in CACNA1G and CACNA1H. Overall, the studies of the Cav3 channelopathies help deciphering the pathogenic mechanisms of corresponding diseases and better delineate the properties and physiological roles Cav3 channels.
Collapse
Affiliation(s)
- Philippe Lory
- Institut de Génomique Fonctionnelle, CNRS, INSERM, University Montpellier, 141, rue de la Cardonille, 34094, Montpellier, France. .,LabEx 'Ion Channel Science and Therapeutics' (ICST), Montpellier, France.
| | - Sophie Nicole
- Institut de Génomique Fonctionnelle, CNRS, INSERM, University Montpellier, 141, rue de la Cardonille, 34094, Montpellier, France.,LabEx 'Ion Channel Science and Therapeutics' (ICST), Montpellier, France
| | - Arnaud Monteil
- Institut de Génomique Fonctionnelle, CNRS, INSERM, University Montpellier, 141, rue de la Cardonille, 34094, Montpellier, France.,LabEx 'Ion Channel Science and Therapeutics' (ICST), Montpellier, France
| |
Collapse
|
9
|
Cove-Smith A, Sharpe CC, Shattock MJ, Hendry BM. Ion-Channel modulator TH1177 reduces glomerular injury and serum creatinine in chronic mesangial proliferative disease in rats. BMC Nephrol 2020; 21:187. [PMID: 32429914 PMCID: PMC7236127 DOI: 10.1186/s12882-020-01842-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 05/07/2020] [Indexed: 01/17/2023] Open
Abstract
Background T-type calcium channels (TTCC) are involved in mesangial cell proliferation. In acute thy-1 nephritis in the rat TTCC inhibition reduces glomerular damage and cell proliferation. This work is extended here by a study of the non-selective TTCC inhibitor TH1177 in a chronic model of proliferative glomerulonephritis (GN) including late treatment starting after the initial inflammation has resolved. The objective was to determine the effects of TH1177 in a model of chronic mesangioproliferative renal disease. Methods Chronic GN was induced in WKY rats by unilateral nephrectomy (day − 7) followed by day 0 injection of Ox7 thy-1 mAb. Treatment with TH1177 (10–20 mg/Kg daily IP) was started on day 2 (early treatment) or on day 14 (late treatment) and compared to vehicle-treated controls until sacrifice at day 42. Glomerular disease was assessed with a damage score, fibrosis assay, cellular counts and renal function measured by serum creatinine. Results Treatment with TH11777 was associated with reduced serum creatinine, less glomerular damage, reduced fibrosis and reduced glomerular cellularity. The results for early and late TH1177 treatments were essentially the same and differed significantly from vehicle. Conclusions The ion-channel modulator TH1177 is capable of improving glomerular outcome in chronic rat GN even when treatment starts 14 days after initiation of the disease. These data are discussed in the context of the possible targets of TH1177 including TTCC, TRP family, Stim/Orai group and other cation channels. The work supports the use of genetic models to examine the roles of individual cation channels in progressive glomerulonephritis to further define the targets of TH1177.
Collapse
Affiliation(s)
- Andrea Cove-Smith
- Renal Sciences, Department of Inflammation Biology, King's College London, Renal Medicine 10 Cutcombe Road, London, SE5 9RJ, UK.,Barts Health Renal Centre, The Royal London Hospital, E1 1BB, London, UK
| | - Claire C Sharpe
- Renal Sciences, Department of Inflammation Biology, King's College London, Renal Medicine 10 Cutcombe Road, London, SE5 9RJ, UK
| | - Michael J Shattock
- Cardiovascular Sciences, The Rayne Institute, King's College London, London, SE1 7EH, UK
| | - Bruce M Hendry
- Renal Sciences, Department of Inflammation Biology, King's College London, Renal Medicine 10 Cutcombe Road, London, SE5 9RJ, UK.
| |
Collapse
|
10
|
O'Malley JJ, Seibt F, Chin J, Beierlein M. TRPM4 Conductances in Thalamic Reticular Nucleus Neurons Generate Persistent Firing during Slow Oscillations. J Neurosci 2020; 40:4813-23. [PMID: 32414784 DOI: 10.1523/JNEUROSCI.0324-20.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/13/2020] [Accepted: 05/11/2020] [Indexed: 12/21/2022] Open
Abstract
During sleep, neurons in the thalamic reticular nucleus (TRN) participate in distinct types of oscillatory activity. While the reciprocal synaptic circuits between TRN and sensory relay nuclei are known to underlie the generation of sleep spindles, the mechanisms regulating slow (<1 Hz) forms of thalamic oscillations are not well understood. Under in vitro conditions, TRN neurons can generate slow oscillations in a cell-intrinsic manner, with postsynaptic Group 1 metabotropic glutamate receptor activation triggering long-lasting plateau potentials thought to be mediated by both T-type Ca2+ currents and Ca2+-activated nonselective cation currents (ICAN). However, the identity of ICAN and the possible contribution of thalamic circuits to slow rhythmic activity remain unclear. Using thalamic slices derived from adult mice of either sex, we recorded slow forms of rhythmic activity in TRN neurons, which were driven by fast glutamatergic thalamoreticular inputs but did not require postsynaptic Group 1 metabotropic glutamate receptor activation. For a significant fraction of TRN neurons, synaptic inputs or brief depolarizing current steps led to long-lasting plateau potentials and persistent firing (PF), and in turn, resulted in sustained synaptic inhibition in postsynaptic relay neurons of the ventrobasal thalamus (VB). Pharmacological approachesindicated that plateau potentials were triggered by Ca2+ influx through T-type Ca2+ channels and mediated by Ca2+- and voltage-dependent transient receptor potential melastatin 4 (TRPM4) channels. Together, our results suggest that thalamic circuits can generate slow oscillatory activity, mediated by an interplay of TRN-VB synaptic circuits that generate rhythmicity and TRN cell-intrinsic mechanisms that control PF and oscillation frequency.SIGNIFICANCE STATEMENT Slow forms of thalamocortical rhythmic activity are thought to be essential for memory consolidation during sleep and the efficient removal of potentially toxic metabolites. In vivo, thalamic slow oscillations are regulated by strong bidirectional synaptic pathways linking neocortex and thalamus. Therefore, in vitro studies in the isolated thalamus offer important insights about the ability of individual neurons and local circuits to generate different forms of rhythmic activity. We found that circuits formed by GABAergic neurons in the thalamic reticular nucleus and glutamatergic relay neurons in the ventrobasal thalamus generated slow oscillatory activity, which was accompanied by persistent firing in thalamic reticular nucleus neurons. Our results identify both cell-intrinsic and synaptic mechanisms that mediate slow forms of rhythmic activity in thalamic circuits.
Collapse
|
11
|
Souza IA, Gandini MA, Zhang FX, Mitchell WG, Matsumoto J, Lerner J, Pierson TM, Zamponi GW. Pathogenic Cav3.2 channel mutation in a child with primary generalized epilepsy. Mol Brain 2019; 12:86. [PMID: 31651342 PMCID: PMC6814130 DOI: 10.1186/s13041-019-0509-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 08/28/2019] [Accepted: 10/02/2019] [Indexed: 12/31/2022] Open
Abstract
Two paternally-inherited missense variants in CACNA1H were identified and characterized in a 6-year-old child with generalized epilepsy. Febrile and unprovoked seizures were present in this child. Both variants were expressed in cis or isolation using human recombinant Cav3.2 calcium channels in tsA-201 cells. Whole-cell patch-clamp recordings indicated that one variant (c.3844C > T; p.R1282W) caused a significant increase in current density consistent with a pathogenic gain-of-function phenotype; while the other cis-related variant (c.5294C > T; p.A1765V) had a benign profile.
Collapse
Affiliation(s)
- Ivana A Souza
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary, AB, T2N 4N1, Canada
| | - Maria A Gandini
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary, AB, T2N 4N1, Canada
| | - Fang-Xiong Zhang
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary, AB, T2N 4N1, Canada
| | - Wendy G Mitchell
- Neurology Division, Children's Hospital Los Angeles & Department of Neurology, Keck School of Medicine of University of Southern California, Los Angeles, USA
| | - Joyce Matsumoto
- Department of Pediatrics, Division of Pediatric Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Jason Lerner
- Department of Pediatrics, Division of Pediatric Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Tyler Mark Pierson
- Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary, AB, T2N 4N1, Canada.
| |
Collapse
|
12
|
Garcia-Caballero A, Zhang FX, Chen L, M'Dahoma S, Huang J, Zamponi GW. SUMOylation regulates USP5-Cav3.2 calcium channel interactions. Mol Brain 2019; 12:73. [PMID: 31455361 PMCID: PMC6712834 DOI: 10.1186/s13041-019-0493-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/19/2019] [Indexed: 12/13/2022] Open
Abstract
Cav3.2 calcium channels play a key role in nociceptive signaling in the primary afferent pain pathway. We have previously reported the regulation of Cav3.2 calcium channels by the deubiquitinase USP5 and its importance for regulating peripheral transmission of pain signals. Here we describe the regulation of the Cav3.2-USP5 interaction by SUMOylation. We show that endogenous USP5 protein expressed in dorsal root ganglia undergoes SUMOylation, and the level of USP5 SUMOylation is reduced following peripheral nerve injury. SUMO prediction software identified several putative lysines that have the propensity to be targets for SUMO conjugation. A series of single lysine substitutions in an mCherry tagged USP5 construct followed by expression in tsA-201 cells identified lysine K113 as a key target for USP5 SUMO2/3 modification. Finally, Cav3.2 calcium channel immunoprecipitates revealed a stronger interaction of Cav3.2 with a SUMO2/3 resistant USP5-K113R mutant, indicating that SUMO2/3 modification of USP5 reduces its affinity for the calcium channel Cav3.2. Collectively, our data suggest that dysregulation of USP5 SUMOylation after peripheral nerve injury may contribute to the well described alteration in Cav3.2 channel activity during neuropathic pain states.
Collapse
Affiliation(s)
- Agustin Garcia-Caballero
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4N1, Canada
| | - Fang-Xiong Zhang
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4N1, Canada
| | - Lina Chen
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4N1, Canada
| | - Said M'Dahoma
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4N1, Canada
| | - Junting Huang
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4N1, Canada
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4N1, Canada.
| |
Collapse
|
13
|
Lundt A, Seidel R, Soós J, Henseler C, Müller R, Bakki M, Arshaad MI, Ehninger D, Hescheler J, Sachinidis A, Broich K, Wormuth C, Papazoglou A, Weiergräber M. Ca v3.2 T-Type Calcium Channels Are Physiologically Mandatory for the Auditory System. Neuroscience 2019; 409:81-100. [PMID: 31029730 DOI: 10.1016/j.neuroscience.2019.04.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 04/11/2019] [Accepted: 04/12/2019] [Indexed: 02/07/2023]
Abstract
Voltage-gated Ca2+ channels (VGCCs) play key roles in auditory perception and information processing within the inner ear and brainstem. Pharmacological inhibition of low voltage-activated (LVA) T-type Ca2+ channels is related to both age- and noise induced hearing loss in experimental animals and may represent a promising approach to the treatment of auditory impairment of various etiologies. Within the LVA Ca2+ channel subgroup, Cav3.2 is the most prominently expressed T-type channel entity in the cochlea and auditory brainstem. Thus, we performed a complete gender specific click and tone burst based auditory brainstem response (ABR) analysis of Cav3.2+/- and Cav3.2-/- mice, including i.a. temporal progression in hearing loss, amplitude growth function and wave latency analysis as well as a cochlear qPCR based evaluation of other VGCCs transcripts. Our results, based on a self-programmed automated wavelet approach, demonstrate that both heterozygous and Cav3.2 null mutant mice exhibit age-dependent increases in hearing thresholds at 5 months of age. In addition, complex alterations in WI-IV amplitudes and latencies were detected that were not attributable to alterations in the expression of other VGCCs in the auditory tract. Our results clearly demonstrate the important physiological role of Cav3.2 VGCCs in the spatiotemporal organization of auditory processing in young adult mice and suggest potential pharmacological targets for interventions in the future.
Collapse
|
14
|
Stemkowski P, García-Caballero A, Gadotti VM, M'Dahoma S, Huang S, Black SAG, Chen L, Souza IA, Zhang Z, Zamponi GW. TRPV1 Nociceptor Activity Initiates USP5/ T-type Channel-Mediated Plasticity. Cell Rep 2016; 17:2901-12. [PMID: 27974205 DOI: 10.1016/j.celrep.2016.11.047] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/30/2016] [Accepted: 11/14/2016] [Indexed: 12/23/2022] Open
Abstract
Peripheral nerve injury and tissue inflammation result in upregulation of the deubiquitinase USP5, thus causing a dysregulation of T-type calcium channel activity and increased pain sensitivity. Here, we have explored the role of afferent fiber activity in this process. Conditioning stimulation of optogenetically targeted cutaneous TRPV1 expressing nociceptors, but not that of non-nociceptive fibers, resulted in enhanced expression of USP5 in mouse dorsal root ganglia and spinal dorsal horn, along with decreased withdrawal thresholds for thermal and mechanical stimuli that abated after 24 hr. This sensitization was drastically reduced by an interfering peptide that prevented USP5-Cav3.2 association. Sensitization was relieved by pharmacological block of TRPV1 afferents, but not of myelinated neurons. In spinal cord slice recordings, we could optogenetically trigger an activity-dependent potentiation of presynaptic neurotransmission in the spinal dorsal horn that relied on Cav3.2 channel activity. This neuronal-activity-induced USP5 upregulation may underlie a protective, transient sensitization of the pain pathway.
Collapse
|
15
|
Gilbert G, Courtois A, Dubois M, Cussac LA, Ducret T, Lory P, Marthan R, Savineau JP, Quignard JF. T-type voltage gated calcium channels are involved in endothelium-dependent relaxation of mice pulmonary artery. Biochem Pharmacol 2017; 138:61-72. [PMID: 28438566 DOI: 10.1016/j.bcp.2017.04.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 04/18/2017] [Indexed: 10/19/2022]
Abstract
In pulmonary arterial endothelial cells, Ca2+ channels and intracellular Ca2+ concentration ([Ca2+]i) control the release of vasorelaxant factors such as nitric oxide and are involved in the regulation of pulmonary arterial blood pressure. The present study was undertaken to investigate the implication of T-type voltage-gated Ca2+ channels (T-VGCCs, Cav3.1 channel) in the endothelium-dependent relaxation of intrapulmonary arteries. Relaxation was quantified by means of a myograph in wild type and Cav3.1-/- mice. Endothelial [Ca2+]i and NO production were measured, on whole vessels, with the fluo-4 and DAF-fm probes. Acetylcholine (ACh) induced a nitric oxide- and endothelium-dependent relaxation that was significantly reduced in pulmonary arteries from Cav3.1-/- compared to wild type mice as well as in the presence of T-VGCC inhibitors (NNC 55-0396 or mibefradil). ACh also increased endothelial [Ca2+]i and NO production that were both reduced in Cav3.1-/- compared to wild type mice or in the presence of T-VGCC inhibitors. Immunofluorescence labeling revealed the presence of Cav3.1 channels in endothelial cells that co-localized with endothelial nitric oxide synthase in arteries from wild type mice. TRPV4-, beta2 adrenergic- and nitric oxide donors (SNP)-mediated relaxation were not altered in Cav3.1-/- compared to wild type mice. Finally, in chronically hypoxic mice, a model of pulmonary hypertension, ACh relaxation was reduced but still depended on Cav3.1 channels activity. The present study thus demonstrates that T-VGCCs, mainly Cav3.1 channel, contribute to intrapulmonary vascular reactivity in mice by controlling endothelial [Ca2+]i and ACh-mediated relaxation.
Collapse
Affiliation(s)
- Guillaume Gilbert
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France
| | - Arnaud Courtois
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France
| | - Mathilde Dubois
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France
| | - Laure-Anne Cussac
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France
| | - Thomas Ducret
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France
| | - Philippe Lory
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, Montpellier F-34094, France; Inserm U1191, Montpellier F-34094, France; Université de Montpellier, Montpellier F-34094, France; LabEx 'Ion Channel Science and Therapeutics', Montpellier F-34094, France
| | - Roger Marthan
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France; CHU de Bordeaux, Bordeaux F-33000, France
| | - Jean-Pierre Savineau
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France
| | - Jean-François Quignard
- Univ Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux F-33000, France; Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux F-33000, France.
| |
Collapse
|
16
|
Papazoglou A, Henseler C, Lundt A, Wormuth C, Soos J, Broich K, Ehninger D, Weiergräber M. Gender specific hippocampal whole genome transcriptome data from mice lacking the Ca v2.3 R-type or Ca v3.2 T-type voltage-gated calcium channel. Data Brief 2017; 12:81-6. [PMID: 28393090 DOI: 10.1016/j.dib.2017.03.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/06/2017] [Accepted: 03/15/2017] [Indexed: 11/21/2022] Open
Abstract
Voltage-gated Ca2+ channels are of central relevance in mediating numerous intracellular and transcellular processes including excitation-contraction coupling, excitation secretion-coupling, hormone and neurotransmitter release and gene expression. The Cav2.3 R-type Ca2+ channel is a high-voltage activated channel which plays a crucial role in neurotransmitter release, long-term potentiation and hormone release. Furthermore, Cav2.3 R-type channels were reported to be involved in ictogenesis, epileptogenesis, fear behavior, sleep, pre-and postsynaptic integration and rhythmicity within the hippocampus. Cav3 T-type Ca2+ channels are low-voltage activated and also widely expressed throughout the brain enabling neurons to switch between different firing patterns and to modulate burst activity. Disruption of T-type Ca2+ current has been related to sleep disorders, epilepsy, Parkinson׳s disease, depression, schizophrenia and pain. Cav3.2 ablation was further attributed to elevated anxiety and hippocampal alterations resulting in impaired long-term potentiation and memory. Given the importance of Cav2.3 and Cav3.2 voltage-gated Ca2+ channels within the CNS, particularly the hippocampus, we collected gender specific microarray transcriptome data of murine hippocampal RNA probes using the Affymetrix Exon Expression Chip Mouse Gene 1.0 ST v1. Information presented here includes transcriptome data from Cav2.3+/+, Cav2.3+/−, Cav2.3−/−, Cav3.2+/+, Cav3.2+/− and Cav3.2−/− mice from both genders, the protocol and list of primers used for genotyping animals, the hippocampal RNA isolation procedure and quality controls.
Collapse
|
17
|
Thuesen AD, Lyngsø KS, Rasmussen L, Stubbe J, Skøtt O, Poulsen FR, Pedersen CB, Rasmussen LM, Hansen PBL. P/Q-type and T-type voltage-gated calcium channels are involved in the contraction of mammary and brain blood vessels from hypertensive patients. Acta Physiol (Oxf) 2017; 219:640-651. [PMID: 27273014 DOI: 10.1111/apha.12732] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 03/21/2016] [Accepted: 06/01/2016] [Indexed: 12/12/2022]
Abstract
AIM Calcium channel blockers are widely used in cardiovascular diseases. Besides L-type channels, T- and P/Q-type calcium channels are involved in the contraction of human renal blood vessels. It was hypothesized that T- and P/Q-type channels are involved in the contraction of human brain and mammary blood vessels. METHODS Internal mammary arteries from bypass surgery patients and cerebral arterioles from patients with brain tumours with and without hypertension were tested in a myograph and perfusion set-up. PCR and immunohistochemistry were performed on isolated blood vessels. RESULTS The P/Q-type antagonist ω-agatoxin IVA (10-8 mol L-1 ) and the T-type calcium blocker mibefradil (10-7 mol L-1 ) inhibited KCl depolarization-induced contraction in mammary arteries from hypertensive patients with no effect on blood vessels from normotensive patients. ω-Agatoxin IVA decreased contraction in cerebral arterioles from hypertensive patients. L-type blocker nifedipine abolished the contraction in mammary arteries. PCR analysis showed expression of P/Q-type (Cav 2.1), T-type (Cav 3.1 and Cav 3.2) and L-type (Cav 1.2) calcium channels in mammary and cerebral arteries. Immunohistochemical labelling of mammary and cerebral arteries revealed the presence of Cav 2.1 in endothelial and smooth muscle cells. Cav 3.1 was also detected in mammary arteries. CONCLUSION P/Q- and T-type Cav are present in human internal mammary arteries and in cerebral penetrating arterioles. P/Q- and T-type calcium channels are involved in the contraction of mammary arteries from hypertensive patients but not from normotensive patients. Furthermore, in cerebral arterioles P/Q-type channels importance was restricted to hypertensive patients might lead to that T- and P/Q-type channels could be a new target in hypertensive patients.
Collapse
Affiliation(s)
- A. D. Thuesen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - K. S. Lyngsø
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - L. Rasmussen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - J. Stubbe
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - O. Skøtt
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| | - F. R. Poulsen
- Department of Neurosurgery; Odense University Hospital; Odense Denmark
- Clinical Institute; University of Southern Denmark; Odense Denmark
| | - C. B. Pedersen
- Department of Neurosurgery; Odense University Hospital; Odense Denmark
| | - L. M. Rasmussen
- Clinical Institute; University of Southern Denmark; Odense Denmark
- Department of Clinical Biochemistry and Pharmacology; Centre for Individualized Medicine in Arterial Diseases; Odense University Hospital; Odense Denmark
| | - P. B. L. Hansen
- Department of Cardiovascular and Renal Research; Institute of Molecular Medicine; University of Southern Denmark; Odense Denmark
| |
Collapse
|
18
|
Cain SM, Ahn S, Garcia E, Zhang Y, Waheed Z, Tyson JR, Yang Y, Van Sung T, Phillips AG, Snutch TP. Heantos-4, a natural plant extract used in the treatment of drug addiction, modulates T-type calcium channels and thalamocortical burst-firing. Mol Brain 2016; 9:94. [PMID: 27919294 PMCID: PMC5139062 DOI: 10.1186/s13041-016-0274-7] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/21/2016] [Indexed: 11/10/2022] Open
Abstract
Heantos-4 is a refined combination of plant extracts currently approved to treat opiate addiction in Vietnam. In addition to its beneficial effects on withdrawal and prevention of relapse, reports of sedation during clinical treatment suggest that arousal networks in the brain may be recruited during Heantos administration. T-type calcium channels are implicated in the generation of sleep rhythms and in this study we examined whether a Heantos-4 extraction modulates T-type calcium channel currents generated by the Cav3.1, Cav3.2 and Ca3.3 subtypes. Utilizing whole-cell voltage clamp on exogenously expressed T-type calcium channels we find that Heantos inhibits Cav3.1 and Cav3.3 currents, while selectively potentiating Cav3.2 currents. We further examined the effects of Heantos-4 extract on low-threshold burst-firing in thalamic neurons which contribute to sleep oscillations. Using whole-cell current clamp in acute thalamic brain slices Heantos-4 suppressed rebound burst-firing in ventrobasal thalamocortical neurons, which express primarily Cav3.1 channels. Conversely, Heantos-4 had no significant effect on the burst-firing properties of thalamic reticular neurons, which express a mixed population of Cav3.2 and Cav3.3 channels. Examining Heantos-4 effects following oral administration in a model of absence epilepsy revealed the potential to exacerbate seizure activity. Together, the findings indicate that Heantos-4 has selective effects both on specific T-type calcium channel isoforms and distinct populations of thalamic neurons providing a putative mechanism underlying its effects on sedation and on the thalamocortical network.
Collapse
Affiliation(s)
- Stuart M Cain
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Soyon Ahn
- Department of Psychiatry, University of British Columbia, Vancouver, Canada
| | - Esperanza Garcia
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Yiming Zhang
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Zeina Waheed
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - John R Tyson
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Yi Yang
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Tran Van Sung
- Institute of Chemistry, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Anthony G Phillips
- Department of Psychiatry, University of British Columbia, Vancouver, Canada
| | - Terrance P Snutch
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 219-2185 East Mall, Vancouver, BC, V6T 1Z4, Canada. .,Department of Psychiatry, University of British Columbia, Vancouver, Canada.
| |
Collapse
|
19
|
Gandhi T, Melge AR, Gopi Mohan C. In silico identification of T-type calcium channel blockers: A ligand-based pharmacophore mapping approach. J Adv Res 2016; 7:931-44. [PMID: 27713840 DOI: 10.1016/j.jare.2016.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 09/07/2016] [Accepted: 09/08/2016] [Indexed: 12/04/2022] Open
Abstract
Limited progress has been made in the quest to identify both selective and non-toxic T-type calcium channel blocking compounds. The present research work was directed toward slaking the same by identifying the selective three dimensional (3D) pharmacophore map for T-type calcium channel blockers (CCBs). Using HipHop module in the CATALYST 4.10 software, both selective and non-selective HipHop pharmacophore maps for T-type CCBs were developed to identify its important common pharmacophoric features. HipHop pharmacophore map of the selective T-type CCBs contained six different chemical features, namely ring aromatic (R), positive ionizable (P), two hydrophobic aromatic (Y), hydrophobic aliphatic (Z), hydrogen bond acceptor (H) and hydrogen bond donor (D). However, non-selective T-type CCBs contain all the above mentioned features except ring aromatic (R). The present ligand-based pharmacophore mapping approach could thus be utilized in classifying selective vs. non-selective T-type CCBs. Further, the model can be used for virtual screening of several small molecule databases.
Collapse
|
20
|
Affiliation(s)
- Mircea C Iftinca
- a Department of Physiology and Pharmacology , Snyder Institute for Chronic Diseases, Inflammation Research Network, University of Calgary , Calgary , Canada
| | - Christophe Altier
- a Department of Physiology and Pharmacology , Snyder Institute for Chronic Diseases, Inflammation Research Network, University of Calgary , Calgary , Canada
| |
Collapse
|
21
|
Bomben VC, Aiba I, Qian J, Mark MD, Herlitze S, Noebels JL. Isolated P/Q Calcium Channel Deletion in Layer VI Corticothalamic Neurons Generates Absence Epilepsy. J Neurosci 2016; 36:405-18. [PMID: 26758833 DOI: 10.1523/JNEUROSCI.2555-15.2016] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Generalized spike-wave seizures involving abnormal synchronization of cortical and underlying thalamic circuitry represent a major category of childhood epilepsy. Inborn errors of Cacna1a, the P/Q-type voltage-gated calcium channel α subunit gene, expressed throughout the brain destabilize corticothalamic rhythmicity and produce this phenotype. To determine the minimal cellular lesion required for this network disturbance, we used neurotensin receptor 1 (Ntsr1) cre-driver mice to ablate floxed Cacna1a in layer VI pyramidal neurons, which supply the sole descending cortical synaptic input to thalamocortical relay cells and reticular interneurons and activate intrathalamic circuits. Targeted Cacna1a ablation in layer VI cells resulted in mice that display a robust spontaneous spike-wave absence seizure phenotype accompanied by behavioral arrest and inhibited by ethosuximide. To verify the selectivity of the molecular lesion, we determined that P/Q subunit proteins were reduced in corticothalamic relay neuron terminal zones, and confirmed that P/Q-mediated glutamate release was reduced at these synapses. Spike-triggered exocytosis was preserved by N-type calcium channel rescue, demonstrating that evoked release at layer VI terminals relies on both P/Q and N-type channels. Whereas intrinsic excitability of the P/Q channel depleted layer VI neurons was unaltered, T-type calcium currents in the postsynaptic thalamic relay and reticular cells were dramatically elevated, favoring rebound bursting and seizure generation. We find that an early P/Q-type release defect, limited to synapses of a single cell-type within the thalamocortical circuit, is sufficient to remodel synchronized firing behavior and produce a stable generalized epilepsy phenotype. SIGNIFICANCE STATEMENT This study dissects a critical component of the corticothalamic circuit in spike-wave epilepsy and identifies the developmental importance of P/Q-type calcium channel-mediated presynaptic glutamate release at layer VI pyramidal neuron terminals. Genetic ablation of Cacna1a in layer VI neurons produced synchronous spike-wave discharges in the cortex and thalamus that were inhibited by ethosuximide. These mice also displayed N-type calcium channel compensation at descending thalamic synapses, and consistent with other spike-wave models increased low-threshold T-type calcium currents within postsynaptic thalamic relay and reticular neurons. These results demonstrate, for the first time, that preventing the developmental homeostatic switch from loose to tightly coupled synaptic release at a single class of deep layer cortical excitatory output neurons results in generalized spike-wave epilepsy.
Collapse
|
22
|
Pudukulatham Z, Zhang FX, Gadotti VM, M'Dahoma S, Swami P, Tamboli Y, Zamponi GW. Synthesis and characterization of a disubstituted piperazine derivative with T-type channel blocking action and analgesic properties. Mol Pain 2016; 12:12/0/1744806916641678. [PMID: 27053601 PMCID: PMC4956396 DOI: 10.1177/1744806916641678] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 01/27/2016] [Indexed: 12/14/2022] Open
Abstract
Background T-type calcium channels are important contributors to signaling in the primary afferent pain pathway and are thus important targets for the development of analgesics. It has been previously reported that certain piperazine-based compounds such as flunarizine are able to inhibit T-type calcium channels. Thus, we hypothesized that novel piperazine compounds could potentially act as analgesics. Results Here, we have created a series of 14 compound derivatives around a diphenyl methyl-piperazine core pharmacophore. Testing their effects on transiently expressed Cav3.2 calcium channels revealed one derivative (3-((4-(bis(4-fluorophenyl)methyl)piperazin-1-yl)methyl)-4-(2-methoxyphenyl)-1,2,5-oxadiazole 2-oxide, compound 10e) as a potent blocker. 10e mediate tonic block of these channels with an IC50 of around 4 micromolar. 10e also blocked Cav3.1 and Cav3.3 channels, but only weakly affected high-voltage-activated Cav1.2 and Cav2.2 channels. Intrathecal delivery of 10e mediated relief from formalin and complete Freund’s adjuvant induced inflammatory pain that was ablated by genetic knockout of Cav3.2 channels. Conclusions Altogether, our data identify a novel T-type calcium channel blocker with tight structure activity relationship (SAR) and relevant in vivo efficacy in inflammatory pain conditions.
Collapse
Affiliation(s)
| | - Fang-Xiong Zhang
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Vinicius M Gadotti
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Said M'Dahoma
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Prabhuling Swami
- School of Chemical Sciences, SRTM University, Nanded, Maharashtra, India
| | - Yasinalli Tamboli
- School of Chemical Sciences, SRTM University, Nanded, Maharashtra, India
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| |
Collapse
|
23
|
Jin J, Zhu L, Tong X, Ness KK. T-type Corrected-Loss Estimation for Error-in-Variable Model. COMMUN STAT-THEOR M 2016; 46:616-627. [PMID: 27840548 PMCID: PMC5100678 DOI: 10.1080/03610926.2014.1002934] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
In this paper, we consider a linear model in which the covariates are measured with errors. We propose a t-type corrected-loss estimation of the covariate effect, when the measurement error follows the Laplace distribution. The proposed estimator is asymptotically normal. In practical studies, some outliers that diminish the robustness of the estimation occur. Simulation studies show that the estimators are resistent to vertical outliers and an application of Six-Minute Walk test is presented to show that the proposed method performs well.
Collapse
Affiliation(s)
- Jiao Jin
- School of Mathematical Sciences, Beijing Normal University, Beijing, PR China
| | - Liang Zhu
- Department of Biostatistics, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Xingwei Tong
- School of Mathematical Sciences, Beijing Normal University, Beijing, PR China
| | - Kirsten K. Ness
- Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, Memphis, TN, USA
| |
Collapse
|
24
|
M'Dahoma S, Gadotti VM, Zhang FX, Park B, Nam JH, Onnis V, Balboni G, Lee JY, Zamponi GW. Effect of the T-type channel blocker KYS-05090S in mouse models of acute and neuropathic pain. Pflugers Arch 2016; 468:193-9. [PMID: 26354962 DOI: 10.1007/s00424-015-1733-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 08/29/2015] [Accepted: 09/02/2015] [Indexed: 12/11/2022]
Abstract
T-type channels are important contributors to the initiation and the maintenance of chronic pain states. Blocking T-type channels is therefore a possible therapeutic strategy for relieving pain. Here, we report the Cav3.2 T-type channel blocking action of a previously reported small organic molecule, KYS-05090S. This compound was able to reduce transiently expressed Cav3.2 currents with low micromolar affinity and mediated a hyperpolarizing shift in half-inactivation potential. KYS-05090S was then tested in models of acute and neuropathic pain. KYS-05090S (10 μg/10 μl delivered intrathecally) significantly reduced acute pain induced by formalin in both the tonic and inflammatory phases. Its antinociceptive effect was not observed when delivered to Cav3.2 null-mice revealing a Cav3.2-dependent mechanism. KYS-05090S also reduced neuropathic pain in a model of partial sciatic nerve injury. Those results indicate that KYS-05090S mediates a potent analgesic effect in inflammatory and neuropathic pain through T-type channel modulation, suggesting that its scaffold could be explored as a new class of analgesic compounds.
Collapse
|
25
|
Harraz OF, Altier C. STIM1-mediated bidirectional regulation of Ca(2+) entry through voltage-gated calcium channels (VGCC) and calcium-release activated channels (CRAC). Front Cell Neurosci 2014; 8:43. [PMID: 24605083 PMCID: PMC3932444 DOI: 10.3389/fncel.2014.00043] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [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: 12/23/2013] [Accepted: 01/29/2014] [Indexed: 11/13/2022] Open
Abstract
The spatial and temporal regulation of cellular calcium signals is modulated via two main Ca(2+) entry routes. Voltage-gated Ca(2+) channels (VGCC) and Ca(2+)-release activated channels (CRAC) enable Ca(2+) flow into electrically excitable and non-excitable cells, respectively. VGCC are well characterized transducers of electrical activity that allow Ca(2+) signaling into the cell in response to action potentials or subthreshold depolarizing stimuli. The identification of STromal Interaction Molecule (STIM) and Orai proteins has provided significant insights into the understanding of CRAC function and regulation. This review will summarize the current state of knowledge of STIM-Orai interaction and their contribution to cellular Ca(2+) handling mechanisms. We will then discuss the bidirectional actions of STIM1 on VGCC and CRAC. In contrast to the stimulatory role of STIM1 on Orai channel activity that facilitates Ca(2+) entry, recent reports indicated the ability of STIM1 to suppress VGCC activity. This new concept changes our traditional understanding of Ca(2+) handling mechanisms and highlights the existence of dynamically regulated signaling complexes of surface expressed ion channels and intracellular store membrane-embedded Ca(2+) sensors. Overall, STIM1 is emerging as a new class of regulatory proteins that fine-tunes Ca(2+) entry in response to endoplasmic/sarcoplasmic reticulum stress.
Collapse
Affiliation(s)
- Osama F Harraz
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Libin Cardiovascular Institute, University of Calgary Calgary, AB, Canada ; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University Alexandria, Egypt
| | - Christophe Altier
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Inflammation Research Network, University of Calgary Calgary, AB, Canada
| |
Collapse
|
26
|
Engbers JDT, Anderson D, Zamponi GW, Turner RW. Signal processing by T-type calcium channel interactions in the cerebellum. Front Cell Neurosci 2013; 7:230. [PMID: 24348329 PMCID: PMC3841819 DOI: 10.3389/fncel.2013.00230] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 11/06/2013] [Indexed: 01/28/2023] Open
Abstract
T-type calcium channels of the Cav3 family are unique among voltage-gated calcium channels due to their low activation voltage, rapid inactivation, and small single channel conductance. These special properties allow Cav3 calcium channels to regulate neuronal processing in the subthreshold voltage range. Here, we review two different subthreshold ion channel interactions involving Cav3 channels and explore the ability of these interactions to expand the functional roles of Cav3 channels. In cerebellar Purkinje cells, Cav3 and intermediate conductance calcium-activated potassium (IKCa) channels form a novel complex which creates a low voltage-activated, transient outward current capable of suppressing temporal summation of excitatory postsynaptic potentials (EPSPs). In large diameter neurons of the deep cerebellar nuclei, Cav3-mediated calcium current (I T) and hyperpolarization-activated cation current (I H) are activated during trains of inhibitory postsynaptic potentials. These currents have distinct, and yet synergistic, roles in the subthreshold domain with I T generating a rebound burst and I H controlling first spike latency and rebound spike precision. However, by shortening the membrane time constant the membrane returns towards resting value at a faster rate, allowing I H to increase the efficacy of I T and increase the range of burst frequencies that can be generated. The net effect of Cav3 channels thus depends on the channels with which they are paired. When expressed in a complex with a KCa channel, Cav3 channels reduce excitability when processing excitatory inputs. If functionally coupled with an HCN channel, the depolarizing effect of Cav3 channels is accentuated, allowing for efficient inversion of inhibitory inputs to generate a rebound burst output. Therefore, signal processing relies not only on the activity of individual subtypes of channels but also on complex interactions between ion channels whether based on a physical complex or by indirect effects on membrane properties.
Collapse
Affiliation(s)
- Jordan D. T. Engbers
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of CalgaryCalgary, Canada
| | - Dustin Anderson
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of CalgaryCalgary, Canada
| | - Gerald W. Zamponi
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of CalgaryCalgary, Canada
| | - Ray W. Turner
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of CalgaryCalgary, Canada
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of CalgaryCalgary, Canada
| |
Collapse
|
27
|
Lambertsen LM, Ingels H, Schønheyder HC, Hoffmann S. Nationwide laboratory-based surveillance of invasive beta-haemolytic streptococci in Denmark from 2005 to 2011. Clin Microbiol Infect 2013; 20:O216-23. [PMID: 24125634 PMCID: PMC4232002 DOI: 10.1111/1469-0691.12378] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/26/2013] [Accepted: 08/24/2013] [Indexed: 12/02/2022]
Abstract
The aim of this work was to describe national surveillance of invasive beta-haemolytic streptococci (BHS) in Denmark and to report overall trends and major findings by groups and types of BHS causing laboratory-confirmed disease from 2005 to 2011. A total of 3063 BHS isolates were received from 2872 patients. Based on confirmed cases the overall annual incidence increased from 6.2 to 8.9 per 100 000 persons between 2005 and 2011. In 2011 the incidences of group A, B, C and G streptococci were 3.1, 2.3, 0.9 and 2.6 per 100 000 persons, respectively. An increase was observed for all groups of BHS, but in particular for group G in men above 65 years of age. Among group A streptococci (GAS), five T-types (1, 28,12, 3,13,B3264 and B3264) represented 71% and five emm-types (1, 28, 3, 89 and 12) 76% of all isolates. Among group B streptococci (GBS) four types (III, Ia, V, Ib) represented 79% of the isolates. Potential coverage for future vaccines against GAS and GBS disease was 76% compared with the 26-valent GAS vaccine and 89% based on GBS serotypes Ia, Ib, II, III and V. The number of reported cases of invasive BHS disease increased in Denmark from 2005 to 2011. Nationwide laboratory-based surveillance of BHS is required to monitor epidemiological changes, explore potential outbreaks and determine potential vaccine coverage.
Collapse
Affiliation(s)
- L M Lambertsen
- National Neisseria and Streptococcus Reference (NSR), Statens Serum Institut, Copenhagen, Denmark
| | | | | | | | | |
Collapse
|
28
|
Abstract
Low-voltage-activated T-type calcium channels act as a major pathway for calcium entry near the resting membrane potential in a wide range of neuronal cell types. Several reports have uncovered an unrecognized feature of T-type channels in the control of vesicular neurotransmitter and hormone release, a process so far thought to be mediated exclusively by high-voltage-activated calcium channels. However, the underlying molecular mechanisms linking T-type calcium channels to vesicular exocytosis have remained enigmatic. In a recent study, we have reported that Ca(v)3.2 T-type channel forms a signaling complex with the neuronal Q-SNARE syntaxin-1A and SNAP-25. This interaction that relies on specific Ca(v)3.2 molecular determinants, not only modulates T-type channel activity, but was also found essential to support low-threshold exocytosis upon Ca(v)3.2 channel expression in MPC 9/3L-AH chromaffin cells. Overall, we have indentified an unrecognized regulation pathway of T-type calcium channels by SNARE proteins, and proposed the first molecular mechanism by which T-type channels could mediate low-threshold exocytosis.
Collapse
Affiliation(s)
- Norbert Weiss
- Hotchkiss Brain Institute; Department of Physiology and Pharmacology; University of Calgary; Calgary, AB Canada
| | | | | |
Collapse
|