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Yao X, Gao S, Yan N. Structural biology of voltage-gated calcium channels. Channels (Austin) 2024; 18:2290807. [PMID: 38062897 PMCID: PMC10761187 DOI: 10.1080/19336950.2023.2290807] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Voltage-gated calcium (Cav) channels mediate Ca2+ influx in response to membrane depolarization, playing critical roles in diverse physiological processes. Dysfunction or aberrant regulation of Cav channels can lead to life-threatening consequences. Cav-targeting drugs have been clinically used to treat cardiovascular and neuronal disorders for several decades. This review aims to provide an account of recent developments in the structural dissection of Cav channels. High-resolution structures have significantly advanced our understanding of the working and disease mechanisms of Cav channels, shed light on the molecular basis for their modulation, and elucidated the modes of actions (MOAs) of representative drugs and toxins. The progress in structural studies of Cav channels lays the foundation for future drug discovery efforts targeting Cav channelopathies.
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Affiliation(s)
- Xia Yao
- TaiKang Center for Life and Medical Sciences, School of Pharmaceutical Sciences, Wuhan University, Wuhan, China
| | - Shuai Gao
- TaiKang Center for Life and Medical Sciences, School of Pharmaceutical Sciences, Wuhan University, Wuhan, China
| | - Nieng Yan
- Beijing Frontier Research Center for Biological Structures, State Key Laboratory of Membrane Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
- Shenzhen Medical Academy of Research and Translation, Shenzhen, China
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2
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Geisler SM, Ottaviani MM, Jacobo-Piqueras N, Theiner T, Mastrolia V, Guarina L, Ebner K, Obermair GJ, Carbone E, Tuluc P. Deletion of the α 2δ-1 calcium channel subunit increases excitability of mouse chromaffin cells. J Physiol 2024; 602:3793-3814. [PMID: 39004870 DOI: 10.1113/jp285681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 06/26/2024] [Indexed: 07/16/2024] Open
Abstract
High voltage-gated Ca2+ channels (HVCCs) shape the electrical activity and control hormone release in most endocrine cells. HVCCs are multi-subunit protein complexes formed by the pore-forming α1 and the auxiliary β, α2δ and γ subunits. Four genes code for the α2δ isoforms. At the mRNA level, mouse chromaffin cells (MCCs) express predominantly the CACNA2D1 gene coding for the α2δ-1 isoform. Here we show that α2δ-1 deletion led to ∼60% reduced HVCC Ca2+ influx with slower inactivation kinetics. Pharmacological dissection showed that HVCC composition remained similar in α2δ-1-/- MCCs compared to wild-type (WT), demonstrating that α2δ-1 exerts similar functional effects on all HVCC isoforms. Consistent with reduced HVCC Ca2+ influx, α2δ-1-/- MCCs showed reduced spontaneous electrical activity with action potentials (APs) having a shorter half-maximal duration caused by faster rising and decay slopes. However, the induced electrical activity showed opposite effects with α2δ-1-/- MCCs displaying significantly higher AP frequency in the tonic firing mode as well as an increase in the number of cells firing AP bursts compared to WT. This gain-of-function phenotype was caused by reduced functional activation of Ca2+-dependent K+ currents. Additionally, despite the reduced HVCC Ca2+ influx, the intracellular Ca2+ transients and vesicle exocytosis or endocytosis were unaltered in α2δ-1-/- MCCs compared to WT during sustained stimulation. In conclusion, our study shows that α2δ-1 genetic deletion reduces Ca2+ influx in cultured MCCs but leads to a paradoxical increase in catecholamine secretion due to increased excitability. KEY POINTS: Deletion of the α2δ-1 high voltage-gated Ca2+ channel (HVCC) subunit reduces mouse chromaffin cell (MCC) Ca2+ influx by ∼60% but causes a paradoxical increase in induced excitability. MCC intracellular Ca2+ transients are unaffected by the reduced HVCC Ca2+ influx. Deletion of α2δ-1 reduces the immediately releasable pool vesicle exocytosis but has no effect on catecholamine (CA) release in response to sustained stimuli. The increased electrical activity and CA release from MCCs might contribute to the previously reported cardiovascular phenotype of patients carrying α2δ-1 loss-of-function mutations.
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Affiliation(s)
- Stefanie M Geisler
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Matteo M Ottaviani
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Noelia Jacobo-Piqueras
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Tamara Theiner
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Vincenzo Mastrolia
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Laura Guarina
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Karl Ebner
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Gerald J Obermair
- Division of Physiology, Karl Landsteiner University of Health Sciences, Krems, Austria
| | - Emilio Carbone
- Department of Drug Science, NIS Centre, University of Torino, Torino, Italy
| | - Petronel Tuluc
- Department of Pharmacology and Toxicology, Centre for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
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3
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Dyrkheeva NS, Zakharenko AL, Malakhova AA, Okorokova LS, Shtokalo DN, Medvedev SP, Tupikin AA, Kabilov MR, Lavrik OI. Transcriptomic analysis of HEK293A cells with a CRISPR/Cas9-mediated TDP1 knockout. Biochim Biophys Acta Gen Subj 2024; 1868:130616. [PMID: 38621596 DOI: 10.1016/j.bbagen.2024.130616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 03/21/2024] [Accepted: 04/01/2024] [Indexed: 04/17/2024]
Abstract
Tyrosyl-DNA phosphodiesterase 1 (TDP1) is a human DNA repair protein. It is a member of the phospholipase D family based on structural similarity. TDP1 is a key enzyme of the repair of stalled topoisomerase 1 (TOP1)-DNA complexes. Previously, with the CRISPR/Cas9 method, we obtained HEK293A cells with a homozygous knockout of the TDP1 gene and used the TDP1 knockout cells as a cellular model for studying mechanisms of action of an anticancer therapy. In the present work, we hypothesized that the TDP1 knockout would alter the expression of DNA repair-related genes. By transcriptomic analysis, we investigated for the first time the effect of the TDP1 gene knockout on genes' expression changes in the human HEK293A cell line. We obtained original data implying a role of TDP1 in other processes besides the repair of the DNA-TOP1 complex. Differentially expressed gene analysis revealed that TDP1 may participate in cell adhesion and communication, spermatogenesis, mitochondrial function, neurodegeneration, a cytokine response, and the MAPK signaling pathway.
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Affiliation(s)
- Nadezhda S Dyrkheeva
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | - Alexandra L Zakharenko
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | - Anastasia A Malakhova
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; Federal research center Institute of Cytology and Genetics, SB RAS, 10 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | | | - Dmitry N Shtokalo
- AcademGene LLC, 6 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; A.P. Ershov Institute of Informatics Systems, SB RAS, 6 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | - Sergey P Medvedev
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; Federal research center Institute of Cytology and Genetics, SB RAS, 10 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | - Alexey A Tupikin
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | - Marsel R Kabilov
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
| | - Olga I Lavrik
- Institute of Chemical Biology and Fundamental Medicine (ICBFM), Siberian Branch of Russian Academy of Sciences (SB RAS), 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia.
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Sampedro-Castañeda M, Baltussen LL, Lopes AT, Qiu Y, Sirvio L, Mihaylov SR, Claxton S, Richardson JC, Lignani G, Ultanir SK. Epilepsy-linked kinase CDKL5 phosphorylates voltage-gated calcium channel Cav2.3, altering inactivation kinetics and neuronal excitability. Nat Commun 2023; 14:7830. [PMID: 38081835 PMCID: PMC10713615 DOI: 10.1038/s41467-023-43475-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 11/09/2023] [Indexed: 12/18/2023] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are a group of rare childhood disorders characterized by severe epilepsy and cognitive deficits. Numerous DEE genes have been discovered thanks to advances in genomic diagnosis, yet putative molecular links between these disorders are unknown. CDKL5 deficiency disorder (CDD, DEE2), one of the most common genetic epilepsies, is caused by loss-of-function mutations in the brain-enriched kinase CDKL5. To elucidate CDKL5 function, we looked for CDKL5 substrates using a SILAC-based phosphoproteomic screen. We identified the voltage-gated Ca2+ channel Cav2.3 (encoded by CACNA1E) as a physiological target of CDKL5 in mice and humans. Recombinant channel electrophysiology and interdisciplinary characterization of Cav2.3 phosphomutant mice revealed that loss of Cav2.3 phosphorylation leads to channel gain-of-function via slower inactivation and enhanced cholinergic stimulation, resulting in increased neuronal excitability. Our results thus show that CDD is partly a channelopathy. The properties of unphosphorylated Cav2.3 closely resemble those described for CACNA1E gain-of-function mutations causing DEE69, a disorder sharing clinical features with CDD. We show that these two single-gene diseases are mechanistically related and could be ameliorated with Cav2.3 inhibitors.
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Affiliation(s)
| | - Lucas L Baltussen
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Laboratory for the Research of Neurodegenerative Diseases (VIB-KU Leuven), Department of Neurosciences, ON5 Herestraat 49, 3000, Leuven, Belgium
| | - André T Lopes
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Yichen Qiu
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square House, London, WC1N 3BG, UK
| | - Liina Sirvio
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Simeon R Mihaylov
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Suzanne Claxton
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Jill C Richardson
- Neuroscience, MSD Research Laboratories, 120 Moorgate, London, EC2M 6UR, UK
| | - Gabriele Lignani
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square House, London, WC1N 3BG, UK
| | - Sila K Ultanir
- Kinases and Brain Development Lab, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
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5
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Lauerer RJ, Lerche H. Voltage-gated calcium channels in genetic epilepsies. J Neurochem 2023. [PMID: 37822150 DOI: 10.1111/jnc.15983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 09/17/2023] [Accepted: 09/25/2023] [Indexed: 10/13/2023]
Abstract
Voltage-gated calcium channels (VGCC) are abundant in the central nervous system and serve a broad spectrum of functions, either directly in cellular excitability or indirectly to regulate Ca2+ homeostasis. Ca2+ ions act as one of the main connections in excitation-transcription coupling, muscle contraction and excitation-exocytosis coupling, including synaptic transmission. In recent years, many genes encoding VGCCs main α or additional auxiliary subunits have been associated with epilepsy. This review sums up the current state of knowledge on disease mechanisms and provides guidance on disease-specific therapies where applicable.
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Affiliation(s)
- Robert J Lauerer
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University and University Hospital Tuebingen, Tuebingen, Germany
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University and University Hospital Tuebingen, Tuebingen, Germany
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6
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Xing C, Bao L, Li W, Fan H. Progress on role of ion channels of cardiac fibroblasts in fibrosis. Front Physiol 2023; 14:1138306. [PMID: 36969589 PMCID: PMC10033868 DOI: 10.3389/fphys.2023.1138306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 02/27/2023] [Indexed: 03/29/2023] Open
Abstract
Cardiac fibrosis is defined as excessive deposition of extracellular matrix (ECM) in pathological conditions. Cardiac fibroblasts (CFs) activated by injury or inflammation differentiate into myofibroblasts (MFs) with secretory and contractile functions. In the fibrotic heart, MFs produce ECM which is composed mainly of collagen and is initially involved in maintaining tissue integrity. However, persistent fibrosis disrupts the coordination of excitatory contractile coupling, leading to systolic and diastolic dysfunction, and ultimately heart failure. Numerous studies have demonstrated that both voltage- and non-voltage-gated ion channels alter intracellular ion levels and cellular activity, contributing to myofibroblast proliferation, contraction, and secretory function. However, an effective treatment strategy for myocardial fibrosis has not been established. Therefore, this review describes the progress made in research related to transient receptor potential (TRP) channels, Piezo1, Ca2+ release-activated Ca2+ (CRAC) channels, voltage-gated Ca2+ channels (VGCCs), sodium channels, and potassium channels in myocardial fibroblasts with the aim of providing new ideas for treating myocardial fibrosis.
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7
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Correa BH, Moreira CR, Hildebrand ME, Vieira LB. The Role of Voltage-Gated Calcium Channels in Basal Ganglia Neurodegenerative Disorders. Curr Neuropharmacol 2023; 21:183-201. [PMID: 35339179 PMCID: PMC10190140 DOI: 10.2174/1570159x20666220327211156] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/11/2022] [Accepted: 03/14/2022] [Indexed: 11/22/2022] Open
Abstract
Calcium (Ca2+) plays a central role in regulating many cellular processes and influences cell survival. Several mechanisms can disrupt Ca2+ homeostasis to trigger cell death, including oxidative stress, mitochondrial damage, excitotoxicity, neuroinflammation, autophagy, and apoptosis. Voltage-gated Ca2+ channels (VGCCs) act as the main source of Ca2+ entry into electrically excitable cells, such as neurons, and they are also expressed in glial cells such as astrocytes and oligodendrocytes. The dysregulation of VGCC activity has been reported in both Parkinson's disease (PD) and Huntington's (HD). PD and HD are progressive neurodegenerative disorders (NDs) of the basal ganglia characterized by motor impairment as well as cognitive and psychiatric dysfunctions. This review will examine the putative role of neuronal VGCCs in the pathogenesis and treatment of central movement disorders, focusing on PD and HD. The link between basal ganglia disorders and VGCC physiology will provide a framework for understanding the neurodegenerative processes that occur in PD and HD, as well as a possible path towards identifying new therapeutic targets for the treatment of these debilitating disorders.
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Affiliation(s)
- Bernardo H.M. Correa
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Carlos Roberto Moreira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Luciene Bruno Vieira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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8
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Archana GM, Arunkumar RC, Omkumar RV. Assays for L-type voltage gated calcium channels. Anal Biochem 2022; 656:114827. [PMID: 35964733 DOI: 10.1016/j.ab.2022.114827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/10/2022] [Accepted: 07/19/2022] [Indexed: 11/01/2022]
Abstract
Voltage gated calcium channels (VGCCs) are pursued as drug targets for neurodegenerative and cardiovascular diseases. High throughput drug screening targeting VGCCs depends on patch-clamp electrophysiology or fluorophore-based calcium imaging that requires powerful equipment and specialized expertise thus leading to cost escalation. Moreover, VGCC needs to be transfected into cell lines such as HEK-293. We report the presence of L-type VGCC (L-VGCC) subunit proteins, Cav1.2, α2δ and β in HEK-293 cells and the application of simple methods for its assay. Endogenous expression of the channel in HEK-293 cells overcomes the need for transfection. L-VGCC in HEK-293 cells was activated either by the agonist, BayK8644 or by KCl-mediated depolarization. Activity was detected using the calcium sensing probe, GCaMP6m by live imaging. L-VGCC activity induced enhancement in GCaMP6m fluorescence returned to baseline corresponding to channel-closure. Activity was also shown using a methodology involving end-point detection of the calcium dependent interaction of α-CaMKII with NMDA receptor subunit GluN2B sequence. This methodology further simplifies the assay as it eliminates the need for real time imaging. Activation was blocked by the specific L-type VGCC antagonist, nifedipine. Finding the protein and activity of L-VGCC in HEK-293 cells offers commercially viable assays for drug screening.
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Affiliation(s)
- G M Archana
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P. O., Thiruvananthapuram, 695014, India; University of Kerala, India
| | - R C Arunkumar
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P. O., Thiruvananthapuram, 695014, India; University of Kerala, India
| | - R V Omkumar
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P. O., Thiruvananthapuram, 695014, India.
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9
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Siller A, Hofer NT, Tomagra G, Burkert N, Hess S, Benkert J, Gaifullina A, Spaich D, Duda J, Poetschke C, Vilusic K, Fritz EM, Schneider T, Kloppenburg P, Liss B, Carabelli V, Carbone E, Ortner NJ, Striessnig J. β2-subunit alternative splicing stabilizes Cav2.3 Ca 2+ channel activity during continuous midbrain dopamine neuron-like activity. eLife 2022; 11:e67464. [PMID: 35792082 PMCID: PMC9307272 DOI: 10.7554/elife.67464] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
In dopaminergic (DA) Substantia nigra (SN) neurons Cav2.3 R-type Ca2+-currents contribute to somatodendritic Ca2+-oscillations. This activity may contribute to the selective degeneration of these neurons in Parkinson's disease (PD) since Cav2.3-knockout is neuroprotective in a PD mouse model. Here, we show that in tsA-201-cells the membrane-anchored β2-splice variants β2a and β2e are required to stabilize Cav2.3 gating properties allowing sustained Cav2.3 availability during simulated pacemaking and enhanced Ca2+-currents during bursts. We confirmed the expression of β2a- and β2e-subunit transcripts in the mouse SN and in identified SN DA neurons. Patch-clamp recordings of mouse DA midbrain neurons in culture and SN DA neurons in brain slices revealed SNX-482-sensitive R-type Ca2+-currents with voltage-dependent gating properties that suggest modulation by β2a- and/or β2e-subunits. Thus, β-subunit alternative splicing may prevent a fraction of Cav2.3 channels from inactivation in continuously active, highly vulnerable SN DA neurons, thereby also supporting Ca2+ signals contributing to the (patho)physiological role of Cav2.3 channels in PD.
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Affiliation(s)
- Anita Siller
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of InnsbruckInnsbruckAustria
| | - Nadja T Hofer
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of InnsbruckInnsbruckAustria
| | - Giulia Tomagra
- Department of Drug Science, NIS Centre, University of TorinoTorinoItaly
| | - Nicole Burkert
- Institute of Applied Physiology, University of Ulm, Ulm, GermanyUlmGermany
| | - Simon Hess
- Institute for Zoology, Biocenter, University of CologneCologneGermany
| | - Julia Benkert
- Institute of Applied Physiology, University of Ulm, Ulm, GermanyUlmGermany
| | - Aisylu Gaifullina
- Institute of Applied Physiology, University of Ulm, Ulm, GermanyUlmGermany
| | - Desiree Spaich
- Institute of Applied Physiology, University of Ulm, Ulm, GermanyUlmGermany
| | - Johanna Duda
- Institute of Applied Physiology, University of Ulm, Ulm, GermanyUlmGermany
| | | | - Kristina Vilusic
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of InnsbruckInnsbruckAustria
| | - Eva Maria Fritz
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of InnsbruckInnsbruckAustria
| | - Toni Schneider
- Institute of Neurophysiology, University of CologneCologneGermany
| | - Peter Kloppenburg
- Institute for Zoology, Biocenter, University of CologneCologneGermany
| | - Birgit Liss
- Institute of Applied Physiology, University of Ulm, Ulm, GermanyUlmGermany
- Linacre College & New College, University of OxfordOxfordUnited Kingdom
| | | | - Emilio Carbone
- Department of Drug Science, NIS Centre, University of TorinoTorinoItaly
| | - Nadine Jasmin Ortner
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of InnsbruckInnsbruckAustria
| | - Jörg Striessnig
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of InnsbruckInnsbruckAustria
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10
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Ruiz-Fernández AR, Campos L, Gutierrez-Maldonado SE, Núñez G, Villanelo F, Perez-Acle T. Nanosecond Pulsed Electric Field (nsPEF): Opening the Biotechnological Pandora’s Box. Int J Mol Sci 2022; 23:ijms23116158. [PMID: 35682837 PMCID: PMC9181413 DOI: 10.3390/ijms23116158] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 02/04/2023] Open
Abstract
Nanosecond Pulsed Electric Field (nsPEF) is an electrostimulation technique first developed in 1995; nsPEF requires the delivery of a series of pulses of high electric fields in the order of nanoseconds into biological tissues or cells. They primary effects in cells is the formation of membrane nanopores and the activation of ionic channels, leading to an incremental increase in cytoplasmic Ca2+ concentration, which triggers a signaling cascade producing a variety of effects: from apoptosis up to cell differentiation and proliferation. Further, nsPEF may affect organelles, making nsPEF a unique tool to manipulate and study cells. This technique is exploited in a broad spectrum of applications, such as: sterilization in the food industry, seed germination, anti-parasitic effects, wound healing, increased immune response, activation of neurons and myocites, cell proliferation, cellular phenotype manipulation, modulation of gene expression, and as a novel cancer treatment. This review thoroughly explores both nsPEF’s history and applications, with emphasis on the cellular effects from a biophysics perspective, highlighting the role of ionic channels as a mechanistic driver of the increase in cytoplasmic Ca2+ concentration.
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Affiliation(s)
- Alvaro R. Ruiz-Fernández
- Computational Biology Lab, Centro Científico y Tecnológico de Excelencia Ciencia & Vida, Fundación Ciencia & Vida, Santiago 7780272, Chile; (L.C.); (S.E.G.-M.); (G.N.); (F.V.)
- Facultad de Ingeniería y Tecnología, Universidad San Sebastian, Bellavista 7, Santiago 8420524, Chile
- Correspondence: (A.R.R.-F.); (T.P.-A.)
| | - Leonardo Campos
- Computational Biology Lab, Centro Científico y Tecnológico de Excelencia Ciencia & Vida, Fundación Ciencia & Vida, Santiago 7780272, Chile; (L.C.); (S.E.G.-M.); (G.N.); (F.V.)
- Facultad de Ingeniería y Tecnología, Universidad San Sebastian, Bellavista 7, Santiago 8420524, Chile
| | - Sebastian E. Gutierrez-Maldonado
- Computational Biology Lab, Centro Científico y Tecnológico de Excelencia Ciencia & Vida, Fundación Ciencia & Vida, Santiago 7780272, Chile; (L.C.); (S.E.G.-M.); (G.N.); (F.V.)
- Facultad de Ingeniería y Tecnología, Universidad San Sebastian, Bellavista 7, Santiago 8420524, Chile
| | - Gonzalo Núñez
- Computational Biology Lab, Centro Científico y Tecnológico de Excelencia Ciencia & Vida, Fundación Ciencia & Vida, Santiago 7780272, Chile; (L.C.); (S.E.G.-M.); (G.N.); (F.V.)
| | - Felipe Villanelo
- Computational Biology Lab, Centro Científico y Tecnológico de Excelencia Ciencia & Vida, Fundación Ciencia & Vida, Santiago 7780272, Chile; (L.C.); (S.E.G.-M.); (G.N.); (F.V.)
- Facultad de Ingeniería y Tecnología, Universidad San Sebastian, Bellavista 7, Santiago 8420524, Chile
| | - Tomas Perez-Acle
- Computational Biology Lab, Centro Científico y Tecnológico de Excelencia Ciencia & Vida, Fundación Ciencia & Vida, Santiago 7780272, Chile; (L.C.); (S.E.G.-M.); (G.N.); (F.V.)
- Facultad de Ingeniería y Tecnología, Universidad San Sebastian, Bellavista 7, Santiago 8420524, Chile
- Correspondence: (A.R.R.-F.); (T.P.-A.)
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11
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Zhang J, Yuan H, Yao X, Chen S. Endogenous ion channels expressed in human embryonic kidney (HEK-293) cells. Pflugers Arch 2022; 474:665-680. [PMID: 35567642 DOI: 10.1007/s00424-022-02700-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/25/2022] [Accepted: 04/30/2022] [Indexed: 12/21/2022]
Abstract
Mammalian expression systems, particularly the human embryonic kidney (HEK-293) cells, combined with electrophysiological studies, have greatly benefited our understanding of the function, characteristic, and regulation of various ion channels. It was previously assumed that the existence of endogenous ion channels in native HEK-293 cells could be negligible. Still, more and more ion channels are gradually reported in native HEK-293 cells, which should draw our attention. In this regard, we summarize the different ion channels that are endogenously expressed in HEK-293 cells, including voltage-gated Na+ channels, Ca2+ channels, K+ channels, Cl- channels, nonselective cation channels, TRP channels, acid-sensitive ion channels, and Piezo channels, which may complicate the recording of the heterogeneously expressed ion channels to a certain degree. We noted that the expression patterns and channel profiles varied with different studies, which may be due to the distinct originality of the cells, cell culture conditions, passage numbers, and different recording protocols. Therefore, a better knowledge of endogenous ion channels may help minimize potential problems in characterizing heterologously expressed ion channels. Based on this, it is recommended that HEK-293 cells from unknown sources should be examined before transfection for the characterization of their functional profile, especially when the expression level of exogenous ion channels does not overwhelm the endogenous ion channels largely, or the current amplitude is not significantly higher than the native currents.
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Affiliation(s)
- Jun Zhang
- School of Biomedical Sciences and Li Ka Shing Institute of Health Science, The Chinese University of Hong Kong, Hong Kong, China
| | - Huikai Yuan
- Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xiaoqiang Yao
- School of Biomedical Sciences and Li Ka Shing Institute of Health Science, The Chinese University of Hong Kong, Hong Kong, China
| | - Shuo Chen
- Department of Biopharmaceutical Sciences, School of Pharmacy, Harbin Medical University at Daqing, No. 39 Xinyang Rd, High-tech District, Daqing, 163319, Heilongjiang Province, China.
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12
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Timic Stamenic T, Manzella FM, Maksimovic S, Krishnan K, Covey DF, Jevtovic-Todorovic V, Todorovic SM. Further Evidence that Inhibition of Neuronal Voltage-Gated Calcium Channels Contributes to the Hypnotic Effect of Neurosteroid Analogue, 3β-OH. Front Pharmacol 2022; 13:850658. [PMID: 35677453 PMCID: PMC9169093 DOI: 10.3389/fphar.2022.850658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 04/26/2022] [Indexed: 11/13/2022] Open
Abstract
We recently reported that a neurosteroid analogue with T-channel-blocking properties (3β,5β,17β)-3-hydroxyandrostane-17-carbonitrile (3β-OH), induced hypnosis in rat pups without triggering neuronal apoptosis. Furthermore, we found that the inhibition of the CaV3.1 isoform of T-channels contributes to the hypnotic properties of 3β-OH in adult mice. However, the specific mechanisms underlying the role of other subtypes of voltage-gated calcium channels in thalamocortical excitability and oscillations in vivo during 3β-OH-induced hypnosis are largely unknown. Here, we used patch-clamp recordings from acute brain slices, in vivo electroencephalogram (EEG) recordings, and mouse genetics with wild-type (WT) and CaV2.3 knock-out (KO) mice to further investigate the molecular mechanisms of neurosteroid-induced hypnosis. Our voltage-clamp recordings showed that 3β-OH inhibited recombinant CaV2.3 currents. In subsequent current-clamp recordings in thalamic slices ex vivo, we found that selective CaV2.3 channel blocker (SNX-482) inhibited stimulated tonic firing and increased the threshold for rebound burst firing in WT animals. Additionally, in thalamic slices we found that 3β-OH inhibited spike-firing more profoundly in WT than in mutant mice. Furthermore, 3β-OH reduced bursting frequencies in WT but not mutant animals. In ensuing in vivo experiments, we found that intra-peritoneal injections of 3β-OH were less effective in inducing LORR in the mutant mice than in the WT mice, with expected sex differences. Furthermore, the reduction in total α, β, and low γ EEG power was more profound in WT than in CaV2.3 KO females over time, while at 60 min after injections of 3β-OH, the increase in relative β power was higher in mutant females. In addition, 3β-OH depressed EEG power more strongly in the male WT than in the mutant mice and significantly increased the relative δ power oscillations in WT male mice in comparison to the mutant male animals. Our results demonstrate for the first time the importance of the CaV2.3 subtype of voltage-gated calcium channels in thalamocortical excitability and the oscillations that underlie neurosteroid-induced hypnosis.
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Affiliation(s)
- Tamara Timic Stamenic
- Department of Anesthesiology, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Francesca M Manzella
- Department of Anesthesiology, University of Colorado, Anschutz Medical Campus, Aurora, United States
- Neuroscience Graduate Program, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Stefan Maksimovic
- Department of Anesthesiology, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Kathiresan Krishnan
- Department of Developmental Biology, Washington University School of Medicine, Saint Louis, MO, United States
| | - Douglas F Covey
- Department of Developmental Biology, Washington University School of Medicine, Saint Louis, MO, United States
- Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, Saint Louis, MO, United States
| | - Vesna Jevtovic-Todorovic
- Department of Anesthesiology, University of Colorado, Anschutz Medical Campus, Aurora, United States
| | - Slobodan M Todorovic
- Department of Anesthesiology, University of Colorado, Anschutz Medical Campus, Aurora, United States
- Neuroscience Graduate Program, University of Colorado, Anschutz Medical Campus, Aurora, United States
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13
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Trevisan G, Oliveira SM. Animal Venom Peptides Cause Antinociceptive Effects by Voltage-gated Calcium Channels Activity Blockage. Curr Neuropharmacol 2022; 20:1579-1599. [PMID: 34259147 PMCID: PMC9881091 DOI: 10.2174/1570159x19666210713121217] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/02/2021] [Accepted: 06/09/2021] [Indexed: 11/22/2022] Open
Abstract
Pain is a complex phenomenon that is usually unpleasant and aversive. It can range widely in intensity, quality, and duration and has diverse pathophysiologic mechanisms and meanings. Voltage-gated sodium and calcium channels are essential to transmitting painful stimuli from the periphery until the dorsal horn of the spinal cord. Thus, blocking voltage-gated calcium channels (VGCCs) can effectively control pain refractory to treatments currently used in the clinic, such as cancer and neuropathic pain. VGCCs blockers isolated of cobra Naja naja kaouthia (α-cobratoxin), spider Agelenopsis aperta (ω-Agatoxin IVA), spider Phoneutria nigriventer (PhTx3.3, PhTx3.4, PhTx3.5, PhTx3.6), spider Hysterocrates gigas (SNX-482), cone snails Conus geographus (GVIA), Conus magus (MVIIA or ziconotide), Conus catus (CVID, CVIE and CVIF), Conus striatus (SO- 3), Conus fulmen (FVIA), Conus moncuri (MoVIA and MoVIB), Conus regularis (RsXXIVA), Conus eburneus (Eu1.6), Conus victoriae (Vc1.1.), Conus regius (RgIA), and spider Ornithoctonus huwena (huwentoxin-I and huwentoxin-XVI) venoms caused antinociceptive effects in different acute and chronic pain models. Currently, ziconotide is the only clinical used N-type VGCCs blocker peptide for chronic intractable pain. However, ziconotide causes different adverse effects, and the intrathecal route of administration also impairs its use in a more significant number of patients. In this sense, peptides isolated from animal venoms or their synthetic forms that act by modulating or blocking VGCCs channels seem to be a relevant prototype for developing new analgesics efficacious and well tolerated by patients.
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Affiliation(s)
- Gabriela Trevisan
- Graduated Program in Pharmacology, Federal University of Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil
| | - Sara Marchesan Oliveira
- Graduated Program in Biological Sciences: Toxicological Biochemistry, Federal University of Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil
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14
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Tuluc P, Theiner T, Jacobo-Piqueras N, Geisler SM. Role of High Voltage-Gated Ca 2+ Channel Subunits in Pancreatic β-Cell Insulin Release. From Structure to Function. Cells 2021; 10:2004. [PMID: 34440773 PMCID: PMC8393260 DOI: 10.3390/cells10082004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/27/2021] [Accepted: 08/03/2021] [Indexed: 02/07/2023] Open
Abstract
The pancreatic islets of Langerhans secrete several hormones critical for glucose homeostasis. The β-cells, the major cellular component of the pancreatic islets, secrete insulin, the only hormone capable of lowering the plasma glucose concentration. The counter-regulatory hormone glucagon is secreted by the α-cells while δ-cells secrete somatostatin that via paracrine mechanisms regulates the α- and β-cell activity. These three peptide hormones are packed into secretory granules that are released through exocytosis following a local increase in intracellular Ca2+ concentration. The high voltage-gated Ca2+ channels (HVCCs) occupy a central role in pancreatic hormone release both as a source of Ca2+ required for excitation-secretion coupling as well as a scaffold for the release machinery. HVCCs are multi-protein complexes composed of the main pore-forming transmembrane α1 and the auxiliary intracellular β, extracellular α2δ, and transmembrane γ subunits. Here, we review the current understanding regarding the role of all HVCC subunits expressed in pancreatic β-cell on electrical activity, excitation-secretion coupling, and β-cell mass. The evidence we review was obtained from many seminal studies employing pharmacological approaches as well as genetically modified mouse models. The significance for diabetes in humans is discussed in the context of genetic variations in the genes encoding for the HVCC subunits.
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Affiliation(s)
- Petronel Tuluc
- Centre for Molecular Biosciences, Department of Pharmacology and Toxicology, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria; (T.T.); (N.J.-P.); (S.M.G.)
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15
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Sundararaj S, Ravindran A, Casarotto MG. AHNAK: The quiet giant in calcium homeostasis. Cell Calcium 2021; 96:102403. [PMID: 33813182 DOI: 10.1016/j.ceca.2021.102403] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 10/21/2022]
Abstract
The phosphoprotein AHNAK is a large, ubiquitously expressed scaffolding protein involved in mediating a host of protein-protein interactions. This enables AHNAK to participate in various multi-protein complexes thereby orchestrating a range of diverse biological processes, including tumour suppression, immune regulation and cell architecture maintenance. A less studied but nonetheless equally important function occurs in calcium homeostasis. It does so by largely interacting with the L-type voltage-gated calcium channel (LVGCC) present in the plasma membrane of excitable cells such as muscles and neurons. Several studies have characterized the underlying basis of AHNAK's functional role in calcium channel modulation, which has led to a greater understanding of this cellular process and its associated pathologies. In this article we review and examine recent advances relating to the physiological aspects of AHNAK in calcium regulation. Specifically, we will provide a broad overview of AHNAK including its structural makeup and its interaction with several isoforms of LVGCC, and how these molecular interactions regulate calcium modulation across various tissues and their implication in muscle and neuronal function.
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Affiliation(s)
- Srinivasan Sundararaj
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra, Australia.
| | - Agin Ravindran
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra, Australia
| | - Marco G Casarotto
- Eccles Institute of Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra, Australia.
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16
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Dolphin AC. Functions of Presynaptic Voltage-gated Calcium Channels. FUNCTION (OXFORD, ENGLAND) 2020; 2:zqaa027. [PMID: 33313507 PMCID: PMC7709543 DOI: 10.1093/function/zqaa027] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/16/2020] [Accepted: 10/20/2020] [Indexed: 01/06/2023]
Abstract
Voltage-gated calcium channels are the principal conduits for depolarization-mediated Ca2+ entry into excitable cells. In this review, the biophysical properties of the relevant members of this family of channels, those that are present in presynaptic terminals, will be discussed in relation to their function in mediating neurotransmitter release. Voltage-gated calcium channels have properties that ensure they are specialized for particular roles, for example, differences in their activation voltage threshold, their various kinetic properties, and their voltage-dependence of inactivation. All these attributes play into the ability of the various voltage-gated calcium channels to participate in different patterns of presynaptic vesicular release. These include synaptic transmission resulting from single action potentials, and longer-term changes mediated by bursts or trains of action potentials, as well as release resulting from graded changes in membrane potential in specialized sensory synapses.
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Affiliation(s)
- Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, WC1E 6BT, UK,Address correspondence to A.C.D. (e-mail: )
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17
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Neumaier F, Schneider T, Albanna W. Ca v2.3 channel function and Zn 2+-induced modulation: potential mechanisms and (patho)physiological relevance. Channels (Austin) 2020; 14:362-379. [PMID: 33079629 PMCID: PMC7583514 DOI: 10.1080/19336950.2020.1829842] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Voltage-gated calcium channels (VGCCs) are critical for Ca2+ influx into all types of excitable cells, but their exact function is still poorly understood. Recent reconstruction of homology models for all human VGCCs at atomic resolution provides the opportunity for a structure-based discussion of VGCC function and novel insights into the mechanisms underlying Ca2+ selective flux through these channels. In the present review, we use these data as a basis to examine the structure, function, and Zn2+-induced modulation of Cav2.3 VGCCs, which mediate native R-type currents and belong to the most enigmatic members of the family. Their unique sensitivity to Zn2+ and the existence of multiple mechanisms of Zn2+ action strongly argue for a role of these channels in the modulatory action of endogenous loosely bound Zn2+, pools of which have been detected in a number of neuronal, endocrine, and reproductive tissues. Following a description of the different mechanisms by which Zn2+ has been shown or is thought to alter the function of these channels, we discuss their potential (patho)physiological relevance, taking into account what is known about the magnitude and function of extracellular Zn2+ signals in different tissues. While still far from complete, the picture that emerges is one where Cav2.3 channel expression parallels the occurrence of loosely bound Zn2+ pools in different tissues and where these channels may serve to translate physiological Zn2+ signals into changes of electrical activity and/or intracellular Ca2+ levels.
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Affiliation(s)
- Felix Neumaier
- Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5) , Jülich, Germany.,University of Cologne, Faculty of Medicine and University Hospital Cologne, Institute of Radiochemistry and Experimental Molecular Imaging , Cologne, Germany
| | - Toni Schneider
- Institute of Neurophysiology , Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Walid Albanna
- Department of Neurosurgery, RWTH Aachen University , Aachen, Germany
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18
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Abstract
Vascular smooth muscle cells (VSMCs) of small peripheral arteries contribute to blood pressure control by adapting their contractile state. These adaptations depend on the VSMC cytosolic Ca2+ concentration, regulated by complex local elementary Ca2+ signaling pathways. Ca2+ sparks represent local, transient, rapid calcium release events from a cluster of ryanodine receptors (RyRs) in the sarcoplasmic reticulum. In arterial SMCs, Ca2+ sparks activate nearby calcium-dependent potassium channels, cause membrane hyperpolarization and thus decrease the global intracellular [Ca2+] to oppose vasoconstriction. Arterial SMC Cav1.2 L-type channels regulate intracellular calcium stores content, which in turn modulates calcium efflux through RyRs. Cav3.2 T-type channels contribute to a minor extend to Ca2+ spark generation in certain types of arteries. Their localization within cell membrane caveolae is essential. We summarize present data on local elementary calcium signaling (Ca2+ sparks) in arterial SMCs with focus on RyR isoforms, large-conductance calcium-dependent potassium (BKCa) channels, and cell membrane-bound calcium channels (Cav1.2 and Cav3.2), particularly in caveolar microdomains.
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Affiliation(s)
- Gang Fan
- Charité - Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany
| | - Yingqiu Cui
- Charité - Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany
| | - Maik Gollasch
- Charité - Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Mario Kassmann
- Charité - Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
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19
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Schneider T, Neumaier F, Hescheler J, Alpdogan S. Cav2.3 R-type calcium channels: from its discovery to pathogenic de novo CACNA1E variants: a historical perspective. Pflugers Arch 2020; 472:811-816. [PMID: 32529299 PMCID: PMC7351833 DOI: 10.1007/s00424-020-02395-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 12/31/2022]
Abstract
So-called pharmacoresistant (R-type) voltage-gated Ca2+ channels are structurally only partially characterized. Most of them are encoded by the CACNA1E gene and are expressed as different Cav2.3 splice variants (variant Cav2.3a to Cav2.3e or f) as the ion conducting subunit. So far, no inherited disease is known for the CACNA1E gene but recently spontaneous mutations leading to early death were identified, which will be brought into focus. In addition, a short historical overview may highlight the development to understand that upregulation during aging, easier activation by spontaneous mutations or lack of bioavailable inorganic cations (Zn2+ and Cu2+) may lead to similar pathologies caused by cellular overexcitation.
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Affiliation(s)
| | - F Neumaier
- Universitat zu Koln, 50931, Köln, Germany
| | | | - S Alpdogan
- Universitat zu Koln, 50931, Köln, Germany
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20
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Dolphin AC, Lee A. Presynaptic calcium channels: specialized control of synaptic neurotransmitter release. Nat Rev Neurosci 2020; 21:213-229. [PMID: 32161339 PMCID: PMC7873717 DOI: 10.1038/s41583-020-0278-2] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2020] [Indexed: 11/09/2022]
Abstract
Chemical synapses are heterogeneous junctions formed between neurons that are specialized for the conversion of electrical impulses into the exocytotic release of neurotransmitters. Voltage-gated Ca2+ channels play a pivotal role in this process as they are the major conduits for the Ca2+ ions that trigger the fusion of neurotransmitter-containing vesicles with the presynaptic membrane. Alterations in the intrinsic function of these channels and their positioning within the active zone can profoundly alter the timing and strength of synaptic output. Advances in optical and electron microscopic imaging, structural biology and molecular techniques have facilitated recent breakthroughs in our understanding of the properties of voltage-gated Ca2+ channels that support their presynaptic functions. Here we examine the nature of these channels, how they are trafficked to and anchored within presynaptic boutons, and the mechanisms that allow them to function optimally in shaping the flow of information through neural circuits.
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Affiliation(s)
- Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.
| | - Amy Lee
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA.
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21
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Kumar A. Calcium Signaling During Brain Aging and Its Influence on the Hippocampal Synaptic Plasticity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:985-1012. [PMID: 31646542 DOI: 10.1007/978-3-030-12457-1_39] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Calcium (Ca2+) ions are highly versatile intracellular signaling molecules and are universal second messenger for regulating a variety of cellular and physiological functions including synaptic plasticity. Ca2+ homeostasis in the central nervous system endures subtle dysregulation with advancing age. Research has provided abundant evidence that brain aging is associated with altered neuronal Ca2+ regulation and synaptic plasticity mechanisms. Much of the work has focused on the hippocampus, a brain region critically involved in learning and memory, which is particularly susceptible to dysfunction during aging. The current chapter takes a specific perspective, assessing various Ca2+ sources and the influence of aging on Ca2+ sources and synaptic plasticity in the hippocampus. Integrating the knowledge of the complexity of age-related alterations in neuronal Ca2+ signaling and synaptic plasticity mechanisms will positively shape the development of highly effective therapeutics to treat brain disorders including cognitive impairment associated with aging and neurodegenerative disease.
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Affiliation(s)
- Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
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22
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Calcium Signaling in Neurons and Glial Cells: Role of Cav1 channels. Neuroscience 2019; 421:95-111. [DOI: 10.1016/j.neuroscience.2019.09.041] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 11/18/2022]
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23
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Lundt A, Soós J, Seidel R, Henseler C, Müller R, Raj Ginde V, Imran Arshaad M, Ehninger D, Hescheler J, Sachinidis A, Broich K, Wormuth C, Papazoglou A, Weiergräber M. Functional implications of Ca v 2.3 R-type voltage-gated calcium channels in the murine auditory system - novel vistas from brainstem-evoked response audiometry. Eur J Neurosci 2019; 51:1583-1604. [PMID: 31603587 DOI: 10.1111/ejn.14591] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 09/11/2019] [Accepted: 10/08/2019] [Indexed: 12/25/2022]
Abstract
Voltage-gated Ca2+ channels (VGCCs) are considered to play a key role in auditory perception and information processing within the murine inner ear and brainstem. In the past, Cav 1.3 L-type VGCCs gathered most attention as their ablation causes congenital deafness. However, isolated patch-clamp investigation and localization studies repetitively suggested that Cav 2.3 R-type VGCCs are also expressed in the cochlea and further components of the ascending auditory tract, pointing to a potential functional role of Cav 2.3 in hearing physiology. Thus, we performed auditory profiling of Cav 2.3+/+ controls, heterozygous Cav 2.3+/- mice and Cav 2.3 null mutants (Cav 2.3-/- ) using brainstem-evoked response audiometry. Interestingly, click-evoked auditory brainstem responses (ABRs) revealed increased hearing thresholds in Cav 2.3+/- mice from both genders, whereas no alterations were observed in Cav 2.3-/- mice. Similar observations were made for tone burst-related ABRs in both genders. However, Cav 2.3 ablation seemed to prevent mutant mice from total hearing loss particularly in the higher frequency range (36-42 kHz). Amplitude growth function analysis revealed, i.a., significant reduction in ABR wave WI and WIII amplitude in mutant animals. In addition, alterations in WI -WIV interwave interval were observed in female Cav 2.3+/- mice whereas absolute latencies remained unchanged. In summary, our results demonstrate that Cav 2.3 VGCCs are mandatory for physiological auditory information processing in the ascending auditory tract.
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Affiliation(s)
- Andreas Lundt
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Julien Soós
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Robin Seidel
- Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Christina Henseler
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Ralf Müller
- Cognitive Neurophysiology, Department of Psychiatry and Psychotherapy and University Hospital Cologne, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Varun Raj Ginde
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Muhammad Imran Arshaad
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Dan Ehninger
- Molecular and Cellular Cognition, German Center for Neurodegenerative Diseases, (Deutsches Zentrum für Neurodegenerative Erkrankungen, DZNE), Bonn, Germany
| | - Jürgen Hescheler
- Institute of Neurophysiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Agapios Sachinidis
- Institute of Neurophysiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Karl Broich
- Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Carola Wormuth
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Anna Papazoglou
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
| | - Marco Weiergräber
- Experimental Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (Bundesinstitut für Arzneimittel und Medizinprodukte, BfArM), Bonn, Germany
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24
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Abstract
This review will first describe the importance of Ca2+ entry for function of excitable cells, and the subsequent discovery of voltage-activated calcium conductances in these cells. This finding was rapidly followed by the identification of multiple subtypes of calcium conductance in different tissues. These were initially termed low- and high-voltage activated currents, but were then further subdivided into L-, N-, PQ-, R- and T-type calcium currents on the basis of differing pharmacology, voltage-dependent and kinetic properties, and single channel conductance. Purification of skeletal muscle calcium channels allowed the molecular identification of the pore-forming and auxiliary α2δ, β and ϒ subunits present in these calcium channel complexes. These advances then led to the cloning of the different subunits, which permitted molecular characterisation, to match the cloned channels with physiological function. Studies with knockout and other mutant mice then allowed further investigation of physiological and pathophysiological roles of calcium channels. In terms of pharmacology, cardiovascular L-type channels are targets for the widely used antihypertensive 1,4-dihydropyridines and other calcium channel blockers, N-type channels are a drug target in pain, and α2δ-1 is the therapeutic target of the gabapentinoid drugs, used in neuropathic pain. Recent structural advances have allowed a deeper understanding of Ca2+ permeation through the channel pore and the structure of both the pore-forming and auxiliary subunits. Voltage-gated calcium channels are subject to multiple pathways of modulation by G-protein and second messenger regulation. Furthermore, their trafficking pathways, subcellular localisation and functional specificity are the subjects of active investigation.
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Voltage-Dependent Calcium Channels, Calcium Binding Proteins, and Their Interaction in the Pathological Process of Epilepsy. Int J Mol Sci 2018; 19:ijms19092735. [PMID: 30213136 PMCID: PMC6164075 DOI: 10.3390/ijms19092735] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/06/2018] [Accepted: 09/07/2018] [Indexed: 01/08/2023] Open
Abstract
As an important second messenger, the calcium ion (Ca2+) plays a vital role in normal brain function and in the pathophysiological process of different neurodegenerative diseases including Alzheimer’s disease (AD), Parkinson’s disease (PD), and epilepsy. Ca2+ takes part in the regulation of neuronal excitability, and the imbalance of intracellular Ca2+ is a trigger factor for the occurrence of epilepsy. Several anti-epileptic drugs target voltage-dependent calcium channels (VDCCs). Intracellular Ca2+ levels are mainly controlled by VDCCs located in the plasma membrane, the calcium-binding proteins (CBPs) inside the cytoplasm, calcium channels located on the intracellular calcium store (particular the endoplasmic reticulum/sarcoplasmic reticulum), and the Ca2+-pumps located in the plasma membrane and intracellular calcium store. So far, while many studies have established the relationship between calcium control factors and epilepsy, the mechanism of various Ca2+ regulatory factors in epileptogenesis is still unknown. In this paper, we reviewed the function, distribution, and alteration of VDCCs and CBPs in the central nervous system in the pathological process of epilepsy. The interaction of VDCCs with CBPs in the pathological process of epilepsy was also summarized. We hope this review can provide some clues for better understanding the mechanism of epileptogenesis, and for the development of new anti-epileptic drugs targeting on VDCCs and CBPs.
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N'Gouemo P. Voltage-Sensitive Calcium Channels in the Brain: Relevance to Alcohol Intoxication and Withdrawal. Handb Exp Pharmacol 2018; 248:263-280. [PMID: 29500720 DOI: 10.1007/164_2018_93] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Voltage-sensitive Ca2+ (CaV) channels are the primary route of depolarization-induced Ca2+ entry in neurons and other excitable cells, leading to an increase in intracellular Ca2+ concentration ([Ca2+]i). The resulting increase in [Ca2+]i activates a wide range of Ca2+-dependent processes in neurons, including neurotransmitter release, gene transcription, activation of Ca2+-dependent enzymes, and activation of certain K+ channels and chloride channels. In addition to their key roles under physiological conditions, CaV channels are also an important target of alcohol, and alcohol-induced changes in Ca2+ signaling can disturb neuronal homeostasis, Ca2+-mediated gene transcription, and the function of neuronal circuits, leading to various neurological and/or neuropsychiatric symptoms and disorders, including alcohol withdrawal induced-seizures and alcoholism.
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Affiliation(s)
- Prosper N'Gouemo
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA.
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27
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Schneider T, Alpdogan S, Hescheler J, Neumaier F. In vitro and in vivo phosphorylation of the Ca v2.3 voltage-gated R-type calcium channel. Channels (Austin) 2018; 12:326-334. [PMID: 30165790 PMCID: PMC6986797 DOI: 10.1080/19336950.2018.1516984] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 08/20/2018] [Accepted: 08/22/2018] [Indexed: 02/07/2023] Open
Abstract
During the recording of whole cell currents from stably transfected HEK-293 cells, the decline of currents carried by the recombinant human Cav2.3+β3 channel subunits is related to adenosine triphosphate (ATP) depletion after rupture of the cells. It reduces the number of functional channels and leads to a progressive shift of voltage-dependent gating to more negative potentials (Neumaier F., et al., 2018). Both effects can be counteracted by hydrolysable ATP, whose protective action is almost completely prevented by inhibition of serine/threonine but not tyrosine or lipid kinases. These findings indicate that ATP promotes phosphorylation of either the channel or an associated protein, whereas dephosphorylation during cell dialysis results in run-down. Protein phosphorylation is required for Cav2.3 channel function and could directly influence the normal features of current carried by these channels. Therefore, results from in vitro and in vivo phosphorylation of Cav2.3 are summarized to come closer to a functional analysis of structural variations in Cav2.3 splice variants.
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Affiliation(s)
- T. Schneider
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Cologne, Germany
| | - S. Alpdogan
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Cologne, Germany
| | - J. Hescheler
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Cologne, Germany
| | - F. Neumaier
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, Cologne, Germany
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28
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Hirano M, Takada Y, Wong CF, Yamaguchi K, Kotani H, Kurokawa T, Mori MX, Snutch TP, Ronjat M, De Waard M, Mori Y. C-terminal splice variants of P/Q-type Ca 2+ channel Ca V2.1 α 1 subunits are differentially regulated by Rab3-interacting molecule proteins. J Biol Chem 2017; 292:9365-9381. [PMID: 28377503 DOI: 10.1074/jbc.m117.778829] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 03/26/2017] [Indexed: 11/06/2022] Open
Abstract
Voltage-dependent Ca2+ channels (VDCCs) mediate neurotransmitter release controlled by presynaptic proteins such as the scaffolding proteins Rab3-interacting molecules (RIMs). RIMs confer sustained activity and anchoring of synaptic vesicles to the VDCCs. Multiple sites on the VDCC α1 and β subunits have been reported to mediate the RIMs-VDCC interaction, but their significance is unclear. Because alternative splicing of exons 44 and 47 in the P/Q-type VDCC α1 subunit CaV2.1 gene generates major variants of the CaV2.1 C-terminal region, known for associating with presynaptic proteins, we focused here on the protein regions encoded by these two exons. Co-immunoprecipitation experiments indicated that the C-terminal domain (CTD) encoded by CaV2.1 exons 40-47 interacts with the α-RIMs, RIM1α and RIM2α, and this interaction was abolished by alternative splicing that deletes the protein regions encoded by exons 44 and 47. Electrophysiological characterization of VDCC currents revealed that the suppressive effect of RIM2α on voltage-dependent inactivation (VDI) was stronger than that of RIM1α for the CaV2.1 variant containing the region encoded by exons 44 and 47. Importantly, in the CaV2.1 variant in which exons 44 and 47 were deleted, strong RIM2α-mediated VDI suppression was attenuated to a level comparable with that of RIM1α-mediated VDI suppression, which was unaffected by the exclusion of exons 44 and 47. Studies of deletion mutants of the exon 47 region identified 17 amino acid residues on the C-terminal side of a polyglutamine stretch as being essential for the potentiated VDI suppression characteristic of RIM2α. These results suggest that the interactions of the CaV2.1 CTD with RIMs enable CaV2.1 proteins to distinguish α-RIM isoforms in VDI suppression of P/Q-type VDCC currents.
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Affiliation(s)
- Mitsuru Hirano
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and
| | - Yoshinori Takada
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and
| | - Chee Fah Wong
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and.,the Department of Biology, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, 35900 Tanjung Malim, Perak, Malaysia
| | - Kazuma Yamaguchi
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and
| | - Hiroshi Kotani
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and
| | - Tatsuki Kurokawa
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and
| | - Masayuki X Mori
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and
| | - Terrance P Snutch
- the Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada, and
| | - Michel Ronjat
- the LabEx Ion Channels, Science and Therapeutics, INSERM UMR1087/CNRS UMR6291, Institut du Thorax, Université de Nantes, Nantes F-44000, France
| | - Michel De Waard
- the LabEx Ion Channels, Science and Therapeutics, INSERM UMR1087/CNRS UMR6291, Institut du Thorax, Université de Nantes, Nantes F-44000, France
| | - Yasuo Mori
- From the Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, and .,the Department of Technology and Ecology, Hall of Global Environmental Studies, Kyoto University, Kyoto 615-8510, Japan
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Multiple nickel-sensitive targets elicit cardiac arrhythmia in isolated mouse hearts after pituitary adenylate cyclase-activating polypeptide-mediated chronotropy. Pharmacol Res 2016; 117:140-147. [PMID: 28007571 DOI: 10.1016/j.phrs.2016.12.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/24/2016] [Accepted: 12/16/2016] [Indexed: 12/11/2022]
Abstract
The pituitary adenylate cyclase-activating polypeptide (PACAP)-27 modulates various biological processes, from the cellular level to function specification. However, the cardiac actions of this neuropeptide are still under intense studies. Using control (+|+) and mice lacking (-|-) either R-type (Cav2.3) or T-type (Cav3.2) Ca2+ channels, we investigated the effects of PACAP-27 on cardiac activity of spontaneously beating isolated perfused hearts. Superfusion of PACAP-27 (20nM) caused a significant increase of baseline heart frequency in Cav2.3(+|+) (156.9±10.8 to 239.4±23.4 bpm; p<0.01) and Cav2.3(-|-) (190.3±26.4 to 270.5±25.8 bpm; p<0.05) hearts. For Cav3.2, the heart rate was significantly increased in Cav3.2(-|-) (133.1±8.5 bpm to 204.6±27.9 bpm; p<0.05) compared to Cav3.2(+|+) hearts (185.7±11.2 bpm to 209.3±22.7 bpm). While the P wave duration and QTc interval were significantly increased in Cav2.3(+|+) and Cav2.3(-|-) hearts following PACAP-27 superfusion, there was no effect in Cav3.2(+|+) and Cav3.2(-|-) hearts. The positive chronotropic effects observed in the four study groups, as well as the effect on P wave duration and QTc interval were abolished in the presence of Ni2+ (50μM) and PACAP-27 (20nM) in hearts from Cav2.3(+|+) and Cav2.3(-|-) mice. In addition to suppressing PACAP's response, Ni2+ also induced conduction disturbances in investigated hearts. In conclusion, the most Ni2+-sensitive Ca2+ channels (R- and T-type) may modulate the PACAP signaling cascade during cardiac excitation in isolated mouse hearts, albeit to a lesser extent than other Ni2+-sensitive targets.
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Barac-Nieto M, Constantinescu A, Pina-Benabou MH, Rozental R. Hypoxic Rise in Cytosolic Calcium and Renal Proximal Tubule Injury Mediated by a Nickel-Sensitive Pathway. Exp Biol Med (Maywood) 2016; 229:1162-8. [PMID: 15564443 DOI: 10.1177/153537020422901111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In the kidney, cell injury resulting from ischemia and hypoxia is thought to be due, in part, to increased cytosolic Ca2+ levels, [Ca2+]i, leading to activation of lytic enzymes, cell dysfunction, and necrosis. We report evidence of a progressive and exponential increase in [Ca2+]i (from 245 ± 10 to 975 ± 100 nM at 45 mins), cell permeabilization and propidium iodide (PI) staining of the nucleus, and partial loss of cell transport functions such as Na+-gradient–dependent uptakes of 14C-alpha-methyiglucopyranoside and inorganic phosphate (32Pi) in proximal convoluted tubules of adult rabbits subjected to hypoxia. The rise in [Ca2+]i depended on the presence of extracellular [Ca2+] and could be blocked by 50 μM Ni2+ but not by verapamil (100 μM). Presence of 50 μM Ni2+ also reduced the hypoxia-induced morphological and functional injuries. We also used HEK 293 cells, a kidney cell line, incubated in media without glucose and exposed for 3.5 hrs to 1% O2–5% CO2 and then returned to glucose-containing media for another 3.5 hrs in an air–5% CO2 atmosphere and finally exposed for 1 min to media containing 1 μM Pl. NiCl2 (50 μM) or pentobarbital (300 μM) more than phenobarbital (1.5 mM), when present in the incubation medium during both the hypoxic and the reoxygenation periods, induced significant (P < 0.001) reductions in the number of cell nuclei stained with Pl, similar to their relative potency as inhibitors of T channels. Our findings indicate that hypoxia-induced alterations in calcium level and subsequent cell injury in the proximal convoluted tubule and in HEK cells involve a nickel-sensitive and dihydropyridine insensitive pathway or channel.
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Affiliation(s)
- M Barac-Nieto
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY 10595, USA
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31
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Wormuth C, Lundt A, Henseler C, Müller R, Broich K, Papazoglou A, Weiergräber M. Review: Ca v2.3 R-type Voltage-Gated Ca 2+ Channels - Functional Implications in Convulsive and Non-convulsive Seizure Activity. Open Neurol J 2016; 10:99-126. [PMID: 27843503 PMCID: PMC5080872 DOI: 10.2174/1874205x01610010099] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 05/16/2016] [Accepted: 06/24/2016] [Indexed: 11/22/2022] Open
Abstract
Background: Researchers have gained substantial insight into mechanisms of synaptic transmission, hyperexcitability, excitotoxicity and neurodegeneration within the last decades. Voltage-gated Ca2+ channels are of central relevance in these processes. In particular, they are key elements in the etiopathogenesis of numerous seizure types and epilepsies. Earlier studies predominantly targeted on Cav2.1 P/Q-type and Cav3.2 T-type Ca2+ channels relevant for absence epileptogenesis. Recent findings bring other channels entities more into focus such as the Cav2.3 R-type Ca2+ channel which exhibits an intriguing role in ictogenesis and seizure propagation. Cav2.3 R-type voltage gated Ca2+ channels (VGCC) emerged to be important factors in the pathogenesis of absence epilepsy, human juvenile myoclonic epilepsy (JME), and cellular epileptiform activity, e.g. in CA1 neurons. They also serve as potential target for various antiepileptic drugs, such as lamotrigine and topiramate. Objective: This review provides a summary of structure, function and pharmacology of VGCCs and their fundamental role in cellular Ca2+ homeostasis. We elaborate the unique modulatory properties of Cav2.3 R-type Ca2+ channels and point to recent findings in the proictogenic and proneuroapoptotic role of Cav2.3 R-type VGCCs in generalized convulsive tonic–clonic and complex-partial hippocampal seizures and its role in non-convulsive absence like seizure activity. Conclusion: Development of novel Cav2.3 specific modulators can be effective in the pharmacological treatment of epilepsies and other neurological disorders.
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Affiliation(s)
- Carola Wormuth
- Department of Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Andreas Lundt
- Department of Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Christina Henseler
- Department of Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Ralf Müller
- Department of Psychiatry and Psychotherapy, University of Cologne, Faculty of Medicine, Cologne, Germany
| | - Karl Broich
- Department of Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Anna Papazoglou
- Department of Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
| | - Marco Weiergräber
- Department of Neuropsychopharmacology, Federal Institute for Drugs and Medical Devices (BfArM), Kurt-Georg-Kiesinger-Allee 3, 53175 Bonn, Germany
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32
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Dolphin AC. Voltage-gated calcium channels and their auxiliary subunits: physiology and pathophysiology and pharmacology. J Physiol 2016; 594:5369-90. [PMID: 27273705 PMCID: PMC5043047 DOI: 10.1113/jp272262] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/09/2016] [Indexed: 12/22/2022] Open
Abstract
Voltage‐gated calcium channels are essential players in many physiological processes in excitable cells. There are three main subdivisions of calcium channel, defined by the pore‐forming α1 subunit, the CaV1, CaV2 and CaV3 channels. For all the subtypes of voltage‐gated calcium channel, their gating properties are key for the precise control of neurotransmitter release, muscle contraction and cell excitability, among many other processes. For the CaV1 and CaV2 channels, their ability to reach their required destinations in the cell membrane, their activation and the fine tuning of their biophysical properties are all dramatically influenced by the auxiliary subunits that associate with them. Furthermore, there are many diseases, both genetic and acquired, involving voltage‐gated calcium channels. This review will provide a general introduction and then concentrate particularly on the role of auxiliary α2δ subunits in both physiological and pathological processes involving calcium channels, and as a therapeutic target.
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Affiliation(s)
- Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.
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33
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Jeong JY, Kweon HJ, Suh BC. Dual Regulation of R-Type CaV2.3 Channels by M1 Muscarinic Receptors. Mol Cells 2016; 39:322-9. [PMID: 26923189 PMCID: PMC4844939 DOI: 10.14348/molcells.2016.2292] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 02/03/2016] [Accepted: 02/05/2016] [Indexed: 11/27/2022] Open
Abstract
Voltage-gated Ca(2+) (CaV) channels are dynamically modulated by G protein-coupled receptors (GPCR). The M1 muscarinic receptor stimulation is known to enhance CaV2.3 channel gating through the activation of protein kinase C (PKC). Here, we found that M1 receptors also inhibit CaV2.3 currents when the channels are fully activated by PKC. In whole-cell configuration, the application of phorbol 12-myristate 13-acetate (PMA), a PKC activator, potentiated CaV2.3 currents by ∼two-fold. After the PMA-induced potentiation, stimulation of M1 receptors decreased the CaV2.3 currents by 52 ± 8%. We examined whether the depletion of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is responsible for the muscarinic suppression of CaV2.3 currents by using two methods: the Danio rerio voltage-sensing phosphatase (Dr-VSP) system and the rapamycin-induced translocatable pseudojanin (PJ) system. First, dephosphorylation of PI(4,5)P2 to phosphatidylinositol 4-phosphate (PI(4)P) by Dr-VSP significantly suppressed CaV2.3 currents, by 53 ± 3%. Next, dephosphorylation of both PI(4)P and PI(4,5)P2 to PI by PJ translocation further decreased the current by up to 66 ± 3%. The results suggest that CaV2.3 currents are modulated by the M1 receptor in a dual mode-that is, potentiation through the activation of PKC and suppression by the depletion of membrane PI(4,5)P2. Our results also suggest that there is rapid turnover between PI(4)P and PI(4,5)P2 in the plasma membrane.
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Affiliation(s)
- Jin-Young Jeong
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988,
Korea
| | - Hae-Jin Kweon
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988,
Korea
| | - Byung-Chang Suh
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988,
Korea
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34
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Thanawala MS, Regehr WG. Determining synaptic parameters using high-frequency activation. J Neurosci Methods 2016; 264:136-152. [PMID: 26972952 DOI: 10.1016/j.jneumeth.2016.02.021] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 02/23/2016] [Accepted: 02/26/2016] [Indexed: 12/25/2022]
Abstract
BACKGROUND The specific properties of a synapse determine how neuronal activity evokes neurotransmitter release. Evaluating changes in synaptic properties during sustained activity is essential to understanding how genetic manipulations and neuromodulators regulate neurotransmitter release. Analyses of postsynaptic responses to high-frequency stimulation have provided estimates of the size of the readily-releasable pool (RRP) of vesicles (N0) and the probability of vesicular release (p) at multiple synapses. NEW METHOD Here, we introduce a model-based approach at the calyx of Held synapse in which depletion and the rate of replenishment (R) determine the number of available vesicles, and facilitation leads to a use-dependent increase in p when initial p is low. RESULTS When p is high and R is low, we find excellent agreement between estimates based on all three methods and the model. However, when p is low or when significant replenishment occurs between stimuli, estimates of different methods diverge, and model estimates are between the extreme estimates provided by the other approaches. COMPARISON WITH OTHER METHODS We compare our model-based approach to three other approaches that rely on different simplifying assumptions. Our findings suggest that our model provides a better estimate of N0 and p than previously-established methods, likely due to inaccurate assumptions about replenishment. More generally, our findings suggest that approaches commonly used to estimate N0 and p at other synapses are often applied under experimental conditions that yield inaccurate estimates. CONCLUSIONS Careful application of appropriate methods can greatly improve estimates of synaptic parameters.
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Affiliation(s)
- Monica S Thanawala
- Department of Neurobiology, Harvard Medical School, Boston, MA, United States
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical School, Boston, MA, United States.
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Heyes S, Pratt WS, Rees E, Dahimene S, Ferron L, Owen MJ, Dolphin AC. Genetic disruption of voltage-gated calcium channels in psychiatric and neurological disorders. Prog Neurobiol 2015; 134:36-54. [PMID: 26386135 PMCID: PMC4658333 DOI: 10.1016/j.pneurobio.2015.09.002] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/08/2015] [Accepted: 09/08/2015] [Indexed: 12/15/2022]
Abstract
Voltage-gated calcium channel classification—genes and proteins. Genetic analysis of neuropsychiatric syndromes. Calcium channel genes identified from GWA studies of psychiatric disorders. Rare mutations in calcium channel genes in psychiatric disorders. Pathophysiological sequelae of CACNA1C mutations and polymorphisms. Monogenic disorders resulting from harmful mutations in other voltage-gated calcium channel genes. Changes in calcium channel gene expression in disease. Involvement of voltage-gated calcium channels in early brain development.
This review summarises genetic studies in which calcium channel genes have been connected to the spectrum of neuropsychiatric syndromes, from bipolar disorder and schizophrenia to autism spectrum disorders and intellectual impairment. Among many other genes, striking numbers of the calcium channel gene superfamily have been implicated in the aetiology of these diseases by various DNA analysis techniques. We will discuss how these relate to the known monogenic disorders associated with point mutations in calcium channels. We will then examine the functional evidence for a causative link between these mutations or single nucleotide polymorphisms and the disease processes. A major challenge for the future will be to translate the expanding psychiatric genetic findings into altered physiological function, involvement in the wider pathology of the diseases, and what potential that provides for personalised and stratified treatment options for patients.
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Affiliation(s)
- Samuel Heyes
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Wendy S Pratt
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Elliott Rees
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Neuroscience and Mental Health Research Institute, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff CF24 4HQ, UK
| | - Shehrazade Dahimene
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Laurent Ferron
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Michael J Owen
- Medical Research Council Centre for Neuropsychiatric Genetics and Genomics, Neuroscience and Mental Health Research Institute, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff CF24 4HQ, UK
| | - Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK.
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36
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Yu XJ, Yang MJ, Zhou B, Wang GZ, Huang YC, Wu LC, Cheng X, Wen ZS, Huang JY, Zhang YD, Gao XH, Li GF, He SW, Gu ZH, Ma L, Pan CM, Wang P, Chen HB, Hong ZP, Wang XL, Mao WJ, Jin XL, Kang H, Chen ST, Zhu YQ, Gu WY, Liu Z, Dong H, Tian LW, Chen SJ, Cao Y, Wang SY, Zhou GB. Characterization of Somatic Mutations in Air Pollution-Related Lung Cancer. EBioMedicine 2015; 2:583-90. [PMID: 26288819 PMCID: PMC4534757 DOI: 10.1016/j.ebiom.2015.04.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 03/26/2015] [Accepted: 04/03/2015] [Indexed: 12/22/2022] Open
Abstract
Air pollution has been classified as Group 1 carcinogenic to humans, but the underlying tumorigenesis remains unclear. In Xuanwei City of Yunnan Province, the lung cancer incidence is among the highest in China attributed to severe air pollution generated by combustion of smoky coal, providing a unique opportunity to dissect lung carcinogenesis of air pollution. Here we analyzed the somatic mutations of 164 non-small cell lung cancers (NSCLCs) from Xuanwei and control regions (CR) where smoky coal was not used. Whole genome sequencing revealed a mean of 289 somatic exonic mutations per tumor and the frequent C:G → A:T nucleotide substitutions in Xuanwei NSCLCs. Exome sequencing of 2010 genes showed that Xuanwei and CR NSCLCs had a mean of 68 and 22 mutated genes per tumor, respectively (p < 0.0001). We found 167 genes (including TP53, RYR2, KRAS, CACNA1E) which had significantly higher mutation frequencies in Xuanwei than CR patients, and mutations in most genes in Xuanwei NSCLCs differed from those in CR cases. The mutation rates of 70 genes (e.g., RYR2, MYH3, GPR144, CACNA1E) were associated with patients' lifetime benzo(a)pyrene exposure. This study uncovers the mutation spectrum of air pollution-related lung cancers, and provides evidence for pollution exposure-genomic mutation relationship at a large scale.
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Affiliation(s)
- Xian-Jun Yu
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Min-Jun Yang
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Bo Zhou
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Gui-Zhen Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Yun-Chao Huang
- Department of Thoracic Surgery, Yunnan Cancer Hospital, Kunming 650106, China
| | - Li-Chuan Wu
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Xin Cheng
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Zhe-Sheng Wen
- Department of Thoracic Surgery, The Cancer Hospital, Sun Yat-Sen University, Guangzhou 510060, China
| | - Jin-Yan Huang
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated to Shanghai Jiao Tong University (SJTU) School of Medicine, and Shanghai Center for Systems Biomedicine, SJTU, Shanghai 200025, China
| | - Yun-Dong Zhang
- Laboratory of Molecular and Experimental Pathology, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Xiao-Hong Gao
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Gao-Feng Li
- Department of Thoracic Surgery, Yunnan Cancer Hospital, Kunming 650106, China
| | - Shui-Wang He
- Laboratory of Molecular and Experimental Pathology, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Zhao-Hui Gu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated to Shanghai Jiao Tong University (SJTU) School of Medicine, and Shanghai Center for Systems Biomedicine, SJTU, Shanghai 200025, China
| | - Liang Ma
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Chun-Ming Pan
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated to Shanghai Jiao Tong University (SJTU) School of Medicine, and Shanghai Center for Systems Biomedicine, SJTU, Shanghai 200025, China
| | - Ping Wang
- Department of Thoracic Surgery, The First People's Hospital of Yunnan Province, Kunming 650032, China
| | - Hao-Bin Chen
- Department of Pathology, The First People's Hospital of Qu Jing City, Qu Jing 655000, Yunnan Province, China
| | - Zhi-Peng Hong
- Department of Thoracic Surgery, The First Affiliated Hospital of Kunming Medical University, Kunming 650032, China
| | - Xiao-Lu Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Wen-Jing Mao
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
- School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Xiao-Long Jin
- Department of Pathology, Rui Jin Hospital Affiliated to SJTU School of Medicine, Shanghai 200025, China
| | - Hui Kang
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Shu-Ting Chen
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Yong-Qiang Zhu
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Wen-Yi Gu
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Zi Liu
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
| | - Hui Dong
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Lin-Wei Tian
- School of Public Health, The University of Hong Kong, Hong Kong SAR, China
| | - Sai-Juan Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital Affiliated to Shanghai Jiao Tong University (SJTU) School of Medicine, and Shanghai Center for Systems Biomedicine, SJTU, Shanghai 200025, China
| | - Yi Cao
- Laboratory of Molecular and Experimental Pathology, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Sheng-Yue Wang
- The Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center, Shanghai 201203, China
| | - Guang-Biao Zhou
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences & University of Chinese Academy of Sciences, Beijing 100101, China
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Tompkins JD, Merriam LA, Girard BM, May V, Parsons RL. Nickel suppresses the PACAP-induced increase in guinea pig cardiac neuron excitability. Am J Physiol Cell Physiol 2015; 308:C857-66. [PMID: 25810261 DOI: 10.1152/ajpcell.00403.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 03/18/2015] [Indexed: 10/23/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a potent intercellular signaling molecule involved in multiple homeostatic functions. PACAP/PAC1 receptor signaling increases excitability of neurons within the guinea pig cardiac ganglia, making them a unique system to establish mechanisms underlying PACAP modulation of neuronal function. Calcium influx is required for the PACAP-increased cardiac neuron excitability, although the pathway is unknown. This study tested whether PACAP enhancement of calcium influx through either T-type or R-type channels contributed to the modulation of excitability. Real-time quantitative polymerase chain reaction analyses indicated transcripts for Cav3.1, Cav3.2, and Cav3.3 T-type isoforms and R-type Cav2.3 in cardiac neurons. These neurons often exhibit a hyperpolarization-induced rebound depolarization that remains when cesium is present to block hyperpolarization-activated nonselective cationic currents (Ih). The T-type calcium channel inhibitors, nickel (Ni(2+)) or mibefradil, suppressed the rebound depolarization, and treatment with both drugs hyperpolarized cardiac neurons by 2-4 mV. Together, these results are consistent with the presence of functional T-type channels, potentially along with R-type channels, in these cardiac neurons. Fifty micromolar Ni(2+), a concentration that suppresses currents in both T-type and R-type channels, blunted the PACAP-initiated increase in excitability. Ni(2+) also blunted PACAP enhancement of the hyperpolarization-induced rebound depolarization and reversed the PACAP-mediated increase in excitability, after being initiated, in a subset of cells. Lastly, low voltage-activated currents, measured under perforated patch whole cell recording conditions and potentially flowing through T-type or R-type channels, were enhanced by PACAP. Together, our results suggest that a PACAP-enhanced, Ni(2+)-sensitive current contributes to PACAP-induced modulation of neuronal excitability.
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Affiliation(s)
- John D Tompkins
- Department of Neurological Sciences, College of Medicine, University of Vermont, Burlington, Vermont
| | - Laura A Merriam
- Department of Neurological Sciences, College of Medicine, University of Vermont, Burlington, Vermont
| | - Beatrice M Girard
- Department of Neurological Sciences, College of Medicine, University of Vermont, Burlington, Vermont
| | - Victor May
- Department of Neurological Sciences, College of Medicine, University of Vermont, Burlington, Vermont
| | - Rodney L Parsons
- Department of Neurological Sciences, College of Medicine, University of Vermont, Burlington, Vermont
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Proft J, Weiss N. G protein regulation of neuronal calcium channels: back to the future. Mol Pharmacol 2014; 87:890-906. [PMID: 25549669 DOI: 10.1124/mol.114.096008] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 12/30/2014] [Indexed: 11/22/2022] Open
Abstract
Neuronal voltage-gated calcium channels have evolved as one of the most important players for calcium entry into presynaptic endings responsible for the release of neurotransmitters. In turn, and to fine-tune synaptic activity and neuronal communication, numerous neurotransmitters exert a potent negative feedback over the calcium signal provided by G protein-coupled receptors. This regulation pathway of physiologic importance is also extensively exploited for therapeutic purposes, for instance in the treatment of neuropathic pain by morphine and other μ-opioid receptor agonists. However, despite more than three decades of intensive research, important questions remain unsolved regarding the molecular and cellular mechanisms of direct G protein inhibition of voltage-gated calcium channels. In this study, we revisit this particular regulation and explore new considerations.
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Affiliation(s)
- Juliane Proft
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Norbert Weiss
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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Simms BA, Zamponi GW. Neuronal voltage-gated calcium channels: structure, function, and dysfunction. Neuron 2014; 82:24-45. [PMID: 24698266 DOI: 10.1016/j.neuron.2014.03.016] [Citation(s) in RCA: 420] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Voltage-gated calcium channels are the primary mediators of depolarization-induced calcium entry into neurons. There is great diversity of calcium channel subtypes due to multiple genes that encode calcium channel α1 subunits, coassembly with a variety of ancillary calcium channel subunits, and alternative splicing. This allows these channels to fulfill highly specialized roles in specific neuronal subtypes and at particular subcellular loci. While calcium channels are of critical importance to brain function, their inappropriate expression or dysfunction gives rise to a variety of neurological disorders, including, pain, epilepsy, migraine, and ataxia. This Review discusses salient aspects of voltage-gated calcium channel function, physiology, and pathophysiology.
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Affiliation(s)
- Brett A Simms
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Gerald W Zamponi
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB T2N 4N1, Canada.
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40
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Simms BA, Souza IA, Rehak R, Zamponi GW. The amino-terminus of high voltage activated calcium channels: CaM you or can't you? Channels (Austin) 2014; 8:370-5. [PMID: 24875328 DOI: 10.4161/chan.29313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Wang K, Lin MT, Adelman JP, Maylie J. Distinct Ca2+ sources in dendritic spines of hippocampal CA1 neurons couple to SK and Kv4 channels. Neuron 2014; 81:379-87. [PMID: 24462100 DOI: 10.1016/j.neuron.2013.11.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2013] [Indexed: 10/25/2022]
Abstract
Small conductance Ca(2+)-activated K(+) (SK) channels and voltage-gated A-type Kv4 channels shape dendritic excitatory postsynaptic potentials (EPSPs) in hippocampal CA1 pyramidal neurons. Synaptically evoked Ca(2+) influx through N-methyl-D-aspartate receptors (NMDARs) activates spine SK channels, reducing EPSPs and the associated spine head Ca(2+) transient. However, results using glutamate uncaging implicated Ca(2+) influx through SNX-482-sensitive (SNX-sensitive) Cav2.3 (R-type) Ca(2+) channels as the Ca(2+) source for SK channel activation. The present findings show that, using Schaffer collateral stimulation, the effects of SNX and apamin are not mutually exclusive and SNX increases EPSPs independent of SK channel activity. Dialysis with 1,2-bis(o-aminophenoxy)ethane-N'N'N'-tetraacetic acid (BAPTA), application of 4-Aminopyridine (4-AP), expression of a Kv4.2 dominant negative subunit, and dialysis with a KChIPs antibody occluded the SNX-induced increase of EPSPs. The results suggest two distinct Ca(2+) signaling pathways within dendritic spines that link Ca(2+) influx through NMDARs to SK channels and Ca(2+) influx through R-type Ca(2+) channels to Kv4.2-containing channels.
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Affiliation(s)
- Kang Wang
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mike T Lin
- Department of Physiology, University of South Alabama, Mobile, AL 36688, USA
| | - John P Adelman
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA.
| | - James Maylie
- Department of Obstetrics and Gynecology, Oregon Health & Science University, Portland, OR 97239, USA.
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Bourinet E, Altier C, Hildebrand ME, Trang T, Salter MW, Zamponi GW. Calcium-permeable ion channels in pain signaling. Physiol Rev 2014; 94:81-140. [PMID: 24382884 DOI: 10.1152/physrev.00023.2013] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The detection and processing of painful stimuli in afferent sensory neurons is critically dependent on a wide range of different types of voltage- and ligand-gated ion channels, including sodium, calcium, and TRP channels, to name a few. The functions of these channels include the detection of mechanical and chemical insults, the generation of action potentials and regulation of neuronal firing patterns, the initiation of neurotransmitter release at dorsal horn synapses, and the ensuing activation of spinal cord neurons that project to pain centers in the brain. Long-term changes in ion channel expression and function are thought to contribute to chronic pain states. Many of the channels involved in the afferent pain pathway are permeable to calcium ions, suggesting a role in cell signaling beyond the mere generation of electrical activity. In this article, we provide a broad overview of different calcium-permeable ion channels in the afferent pain pathway and their role in pain pathophysiology.
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Cardiac functions of voltage-gated Ca(2+) channels: role of the pharmacoresistant type (E-/R-Type) in cardiac modulation and putative implication in sudden unexpected death in epilepsy (SUDEP). Rev Physiol Biochem Pharmacol 2014; 167:115-39. [PMID: 25280639 DOI: 10.1007/112_2014_21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Voltage-gated Ca(2+) channels (VGCCs) are ubiquitous in excitable cells. These channels play key roles in many physiological events like cardiac regulation/pacemaker activity due to intracellular Ca(2+) transients. In the myocardium, the Cav1 subfamily (L-type: Cav1.2 and Cav1.3) is the main contributor to excitation-contraction coupling and/or pacemaking, whereas the Cav3 subfamily (T-type: Cav3.1 and Cav3.2) is important in rhythmically firing of the cardiac nodal cells. No established cardiac function has been attributed to the Cav2 family (E-/R-type: Cav2.3) despite accumulating evidence of cardiac dysregulation observed upon deletion of the Cav2.3 gene, the only member of this family so far detected in cardiomyocytes. In this review, we summarize the pathophysiological changes observed after ablation of the E-/R-type VGCC and propose a cardiac mechanism of action for this channel. Also, considering the role played by this channel in epilepsy and its reported sensitivity to antiepileptic drugs, a putative involvement of this channel in the cardiac mechanism of sudden unexpected death in epilepsy is also discussed.
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Ermolyuk YS, Alder FG, Surges R, Pavlov IY, Timofeeva Y, Kullmann DM, Volynski KE. Differential triggering of spontaneous glutamate release by P/Q-, N- and R-type Ca2+ channels. Nat Neurosci 2013; 16:1754-1763. [PMID: 24185424 PMCID: PMC4176737 DOI: 10.1038/nn.3563] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 10/01/2013] [Indexed: 12/12/2022]
Abstract
The role of voltage-gated Ca2+ channels (VGCCs) in spontaneous miniature neurotransmitter release is incompletely understood. We found that stochastic opening of P/Q-, N- and R-type VGCCs accounts for ∼50% of all spontaneous glutamate release at rat cultured hippocampal synapses, and that R-type channels have a far greater role in spontaneous than in action potential-evoked exocytosis. VGCC-dependent miniature neurotransmitter release (minis) showed similar sensitivity to presynaptic Ca2+ chelation as evoked release, arguing for direct triggering of spontaneous release by transient spatially localized Ca(2+) domains. Experimentally constrained three-dimensional diffusion modeling of Ca2+ influx-exocytosis coupling was consistent with clustered distribution of VGCCs in the active zone of small hippocampal synapses and revealed that spontaneous VGCCs openings can account for the experimentally observed VGCC-dependent minis, although single channel openings triggered release with low probability. Uncorrelated stochastic VGCC opening is therefore a major trigger for spontaneous glutamate release, with differential roles for distinct channel subtypes.
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Affiliation(s)
- Yaroslav S Ermolyuk
- UCL Institute of Neurology, University College London, Queen Square, WC1N 3BG, United Kingdom
| | - Felicity G Alder
- UCL Institute of Neurology, University College London, Queen Square, WC1N 3BG, United Kingdom
| | - Rainer Surges
- UCL Institute of Neurology, University College London, Queen Square, WC1N 3BG, United Kingdom
| | - Ivan Y Pavlov
- UCL Institute of Neurology, University College London, Queen Square, WC1N 3BG, United Kingdom
| | - Yulia Timofeeva
- Department of Computer Science, University of Warwick, Coventry, CV4 7AL, United Kingdom
- Centre for Complexity Science, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Dimitri M Kullmann
- UCL Institute of Neurology, University College London, Queen Square, WC1N 3BG, United Kingdom
| | - Kirill E Volynski
- UCL Institute of Neurology, University College London, Queen Square, WC1N 3BG, United Kingdom
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45
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Münch A, Dibué M, Hescheler J, Schneider T. Cav2.3 E-/R-type voltage-gated calcium channels modulate sleep in mice. SOMNOLOGIE 2013. [DOI: 10.1007/s11818-013-0628-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Schneider T, Dibué M, Hescheler J. How "Pharmacoresistant" is Cav2.3, the Major Component of Voltage-Gated R-type Ca2+ Channels? Pharmaceuticals (Basel) 2013; 6:759-76. [PMID: 24276260 PMCID: PMC3816731 DOI: 10.3390/ph6060759] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 04/26/2013] [Accepted: 05/06/2013] [Indexed: 12/04/2022] Open
Abstract
Membrane-bound voltage-gated Ca2+ channels (VGCCs) are targets for specific signaling complexes, which regulate important processes like gene expression, neurotransmitter release and neuronal excitability. It is becoming increasingly evident that the so called “resistant” (R-type) VGCC Cav2.3 is critical in several physiologic and pathophysiologic processes in the central nervous system, vascular system and in endocrine systems. However its eponymous attribute of pharmacologic inertness initially made in depth investigation of the channel difficult. Although the identification of SNX-482 as a fairly specific inhibitor of Cav2.3 in the nanomolar range has enabled insights into the channels properties, availability of other pharmacologic modulators of Cav2.3 with different chemical, physical and biological properties are of great importance for future investigations. Therefore the literature was screened systematically for molecules that modulate Cav2.3 VGCCs.
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Affiliation(s)
- Toni Schneider
- Institute of Neurophysiology, University of Cologne, Robert-Koch-Str. 39, Cologne D-50931, Germany; E-Mail:
- Authors to whom correspondence should be addressed; E-Mails: (T.S.); (M.D.); Tel.: +49-221-478-69446 (T.S.); Fax: +49-221-478-6965 (T.S.)
| | - Maxine Dibué
- Institute of Neurophysiology, University of Cologne, Robert-Koch-Str. 39, Cologne D-50931, Germany; E-Mail:
- Department for Neurosurgery, Medical Faculty, Heinrich Heine University, Moorenstraße 5, Duesseldorf D-40225, Germany & Center of Molecular Medicine, Cologne D-50931, Germany
- Authors to whom correspondence should be addressed; E-Mails: (T.S.); (M.D.); Tel.: +49-221-478-69446 (T.S.); Fax: +49-221-478-6965 (T.S.)
| | - Jürgen Hescheler
- Institute of Neurophysiology, University of Cologne, Robert-Koch-Str. 39, Cologne D-50931, Germany; E-Mail:
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Presynaptic calcium influx controls neurotransmitter release in part by regulating the effective size of the readily releasable pool. J Neurosci 2013; 33:4625-33. [PMID: 23486937 DOI: 10.1523/jneurosci.4031-12.2013] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The steep calcium dependence of synaptic strength that has been observed at many synapses is thought to reflect a calcium dependence of the probability of vesicular exocytosis (p), with the cooperativity of three to six corresponding to the multiple calcium ion binding sites on the calcium sensor responsible for exocytosis. Here we test the hypothesis that the calcium dependence of the effective size of the readily releasable pool (RRP) also contributes to the calcium dependence of release at the calyx of Held synapse in mice. Using two established methods of quantifying neurotransmitter release evoked by action potentials (effective RRP), we find that when calcium influx is changed by altering the external calcium concentration, the calcium cooperativity of p is insufficient to account for the full calcium dependence of EPSC size; the calcium dependence of the RRP size also contributes. Reducing calcium influx by blocking R-type voltage-gated calcium channels (VGCCs) with Ni(2+), or by blocking P/Q-type VGCCs with ω-agatoxin IVA also changes EPSC amplitude by reducing both p and the effective RRP size. This suggests that the effective RRP size is dependent on calcium influx through VGCCs. Furthermore, activation of GABAB receptors, which reduces presynaptic calcium through VGCCs without other significant effects on release, also reduces the effective RRP size in addition to reducing p. These findings indicate that calcium influx regulates the RRP size along with p, which contributes to the calcium dependence of synaptic strength, and it influences the manner in which presynaptic modulation of presynaptic calcium channels affects neurotransmitter release.
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48
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Flynn R, Altier C. A macromolecular trafficking complex composed of β₂-adrenergic receptors, A-Kinase Anchoring Proteins and L-type calcium channels. J Recept Signal Transduct Res 2013; 33:172-6. [PMID: 23557075 DOI: 10.3109/10799893.2013.782219] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract Sympathetic modulation of cardiac L-type calcium channels is an important mechanism for regulating heart rate and cardiac contractility. At the molecular level, activation of β-adrenergic receptors (βAR) increases calcium influx into cardiac myocytes by activating protein kinase A (PKA), leading to subsequent phosphorylation of L-type calcium channels. In the case of the β2AR, this process is facilitated by the presence of A-Kinase Anchoring Proteins (AKAPs) that serve as scaffolding proteins for the L-type calcium channel and the β2AR complex. Our work has shown that, in addition to facilitating PKA phosphorylation of the channel, AKAPs also promote an increase in the Cav1.2 channel surface expression. Here we review the molecular mechanisms of β2AR/AKAP/L-type channel interactions and trafficking.
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Affiliation(s)
- Robyn Flynn
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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Quantitative regional and ultrastructural localization of the Ca(v)2.3 subunit of R-type calcium channel in mouse brain. J Neurosci 2012; 32:13555-67. [PMID: 23015445 DOI: 10.1523/jneurosci.1142-12.2012] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
R-type calcium channels (RTCCs) are well known for their role in synaptic plasticity, but little is known about their subcellular distribution across various neuronal compartments. Using subtype-specific antibodies, we characterized the regional and subcellular localization of Ca(v)2.3 in mice and rats at both light and electron microscopic levels. Ca(v)2.3 immunogold particles were found to be predominantly presynaptic in the interpeduncular nucleus, but postsynaptic in other brain regions. Serial section analysis of electron microscopic images from the hippocampal CA1 revealed a higher density of immunogold particles in the dendritic shaft plasma membrane compared with the pyramidal cell somata. However, the labeling densities were not significantly different among the apical, oblique, or basal dendrites. Immunogold particles were also observed over the plasma membrane of dendritic spines, including both synaptic and extrasynaptic sites. Individual spine heads contained <20 immunogold particles, with an average density of ∼260 immunoparticles per μm(3) spine head volume, in accordance with the density of RTCCs estimated using calcium imaging (Sabatini and Svoboda, 2000). The Ca(v)2.3 density was variable among similar-sized spine heads and did not correlate with the density in the parent dendrite, implying that spines are individual calcium compartments operating autonomously from their parent dendrites.
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50
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Pérez-Garci E, Larkum ME, Nevian T. Inhibition of dendritic Ca2+ spikes by GABAB receptors in cortical pyramidal neurons is mediated by a direct Gi/o-β-subunit interaction with Cav1 channels. J Physiol 2012. [PMID: 23184512 DOI: 10.1113/jphysiol.2012.245464] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Voltage-dependent calcium channels (VDCCs) serve a wide range of physiological functions and their activity is modulated by different neurotransmitter systems. GABAergic inhibition of VDCCs in neurons has an important impact in controlling transmitter release, neuronal plasticity, gene expression and neuronal excitability. We investigated the molecular signalling mechanisms by which GABA(B) receptors inhibit calcium-mediated electrogenesis (Ca(2+) spikes) in the distal apical dendrite of cortical layer 5 pyramidal neurons. Ca(2+) spikes are the basis of coincidence detection and signal amplification of distal tuft synaptic inputs characteristic for the computational function of cortical pyramidal neurons. By combining dendritic whole-cell recordings with two-photon fluorescence Ca(2+) imaging we found that all subtypes of VDCCs were present in the Ca(2+) spike initiation zone, but that they contribute differently to the initiation and sustaining of dendritic Ca(2+) spikes. Particularly, Ca(v)1 VDCCs are the most abundant VDCC present in this dendritic compartment and they generated the sustained plateau potential characteristic for the Ca(2+) spike. Activation of GABA(B) receptors specifically inhibited Ca(v)1 channels. This inhibition of L-type Ca(2+) currents was transiently relieved by strong depolarization but did not depend on protein kinase activity. Therefore, our findings suggest a novel membrane-delimited interaction of the G(i/o)-βγ-subunit with Ca(v)1 channels identifying this mechanism as the general pathway of GABA(B) receptor-mediated inhibition of VDCCs. Furthermore, the characterization of the contribution of the different VDCCs to the generation of the Ca(2+) spike provides new insights into the molecular mechanism of dendritic computation.
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Affiliation(s)
- Enrique Pérez-Garci
- Department of Physiology, University of Berne, Bühlplatz 5, CH-3012 Bern, Switzerland.
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