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Martín-Belmonte A, Aguado C, Alfaro-Ruiz R, Kulik A, de la Ossa L, Moreno-Martínez AE, Alberquilla S, García-Carracedo L, Fernández M, Fajardo-Serrano A, Aso E, Shigemoto R, Martín ED, Fukazawa Y, Ciruela F, Luján R. Nanoarchitecture of Ca V2.1 channels and GABA B receptors in the mouse hippocampus: Impact of APP/PS1 pathology. Brain Pathol 2024:e13279. [PMID: 38887180 DOI: 10.1111/bpa.13279] [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: 02/06/2024] [Accepted: 05/27/2024] [Indexed: 06/20/2024] Open
Abstract
Voltage-gated CaV2.1 (P/Q-type) Ca2+ channels play a crucial role in regulating neurotransmitter release, thus contributing to synaptic plasticity and to processes such as learning and memory. Despite their recognized importance in neural function, there is limited information on their potential involvement in neurodegenerative conditions such as Alzheimer's disease (AD). Here, we aimed to explore the impact of AD pathology on the density and nanoscale compartmentalization of CaV2.1 channels in the hippocampus in association with GABAB receptors. Histoblotting experiments showed that the density of CaV2.1 channel was significantly reduced in the hippocampus of APP/PS1 mice in a laminar-dependent manner. CaV2.1 channel was enriched in the active zone of the axon terminals and was present at a very low density over the surface of dendritic tree of the CA1 pyramidal cells, as shown by quantitative SDS-digested freeze-fracture replica labelling (SDS-FRL). In APP/PS1 mice, the density of CaV2.1 channel in the active zone was significantly reduced in the strata radiatum and lacunosum-moleculare, while it remained unaltered in the stratum oriens. The decline in Cav2.1 channel density was found to be associated with a corresponding impairment in the GABAergic synaptic function, as evidenced by electrophysiological experiments carried out in the hippocampus of APP/PS1 mice. Remarkably, double SDS-FRL showed a co-clustering of CaV2.1 channel and GABAB1 receptor in nanodomains (~40-50 nm) in wild type mice, while in APP/PS1 mice this nanoarchitecture was absent. Together, these findings suggest that the AD pathology-induced reduction in CaV2.1 channel density and CaV2.1-GABAB1 de-clustering may play a role in the synaptic transmission alterations shown in the AD hippocampus. Therefore, uncovering these layer-dependent changes in P/Q calcium currents associated with AD pathology can benefit the development of future strategies for AD management.
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Affiliation(s)
- Alejandro Martín-Belmonte
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain
| | - Carolina Aguado
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
- Laboratorio de Estructura Sináptica, Instituto de Investigación Sanitaria de Castilla-La Mancha (IDISCAM), Albacete, Spain
| | - Rocío Alfaro-Ruiz
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
- Laboratorio de Estructura Sináptica, Instituto de Investigación Sanitaria de Castilla-La Mancha (IDISCAM), Albacete, Spain
| | - Akos Kulik
- Institute for Physiology II, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Luis de la Ossa
- Departamento de Sistemas Informáticos, Escuela Superior de Ingeniería Informática, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Ana Esther Moreno-Martínez
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
- Laboratorio de Estructura Sináptica, Instituto de Investigación Sanitaria de Castilla-La Mancha (IDISCAM), Albacete, Spain
| | - Samuel Alberquilla
- Laboratory of Neurophysiology and Synaptic Plasticity, Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Lucía García-Carracedo
- Laboratory of Neurophysiology and Synaptic Plasticity, Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Miriam Fernández
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
- Laboratorio de Estructura Sináptica, Instituto de Investigación Sanitaria de Castilla-La Mancha (IDISCAM), Albacete, Spain
| | - Ana Fajardo-Serrano
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
| | - Ester Aso
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain
| | - Ryuichi Shigemoto
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Eduardo D Martín
- Laboratory of Neurophysiology and Synaptic Plasticity, Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Yugo Fukazawa
- Division of Brain Structure and Function, Faculty of Medical Science, University of Fukui, Fukui, Japan
- Life Science Innovation Center, University of Fukui, Fukui, Japan
| | - Francisco Ciruela
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain
| | - Rafael Luján
- Departamento de Ciencias Médicas, Facultad de Medicina, Synaptic Structure Laboratory, Instituto de Biomedicina de la UCLM (IB-UCLM), Universidad Castilla-La Mancha, Albacete, Spain
- Laboratorio de Estructura Sináptica, Instituto de Investigación Sanitaria de Castilla-La Mancha (IDISCAM), Albacete, Spain
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Ye Q, Nunez J, Zhang X. Multiple cholinergic receptor subtypes coordinate dual modulation of acetylcholine on anterior and posterior paraventricular thalamic neurons. J Neurochem 2024; 168:995-1018. [PMID: 38664195 PMCID: PMC11136594 DOI: 10.1111/jnc.16115] [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: 09/28/2023] [Revised: 03/31/2024] [Accepted: 04/05/2024] [Indexed: 05/31/2024]
Abstract
Paraventricular thalamus (PVT) plays important roles in the regulation of emotion and motivation through connecting many brain structures including the midbrain and the limbic system. Although acetylcholine (ACh) neurons of the midbrain were reported to send projections to PVT, little is known about how cholinergic signaling regulates PVT neurons. Here, we used both RNAscope and slice patch-clamp recordings to characterize cholinergic receptor expression and ACh modulation of PVT neurons in mice. We found ACh excited a majority of anterior PVT (aPVT) neurons but predominantly inhibited posterior PVT (pPVT) neurons. Compared to pPVT with more inhibitory M2 receptors, aPVT expressed higher levels of all excitatory receptor subtypes including nicotinic α4, α7, and muscarinic M1 and M3. The ACh-induced excitation was mimicked by nicotine and antagonized by selective blockers for α4β2 and α7 nicotinic ACh receptor (nAChR) subtypes as well as selective antagonists for M1 and M3 muscarinic ACh receptors (mAChR). The ACh-induced inhibition was attenuated by selective M2 and M4 mAChR receptor antagonists. Furthermore, we found ACh increased the frequency of excitatory postsynaptic currents (EPSCs) on a majority of aPVT neurons but decreased EPSC frequency on a larger number of pPVT neurons. In addition, ACh caused an acute increase followed by a lasting reduction in inhibitory postsynaptic currents (IPSCs) on PVT neurons of both subregions. Together, these data suggest that multiple AChR subtypes coordinate a differential modulation of ACh on aPVT and pPVT neurons.
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Affiliation(s)
- Qiying Ye
- Department of Psychology, Florida State University, Tallahassee, FL 32306, USA
| | - Jeremiah Nunez
- Department of Psychology, Florida State University, Tallahassee, FL 32306, USA
| | - Xiaobing Zhang
- Department of Psychology, Florida State University, Tallahassee, FL 32306, USA
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3
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Quiroz-Acosta T, Bermeo K, Arenas I, Garcia DE. G-protein tonic inhibition of calcium channels in pancreatic β-cells. Am J Physiol Cell Physiol 2023; 325:C592-C598. [PMID: 37458440 DOI: 10.1152/ajpcell.00447.2022] [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: 10/07/2022] [Revised: 06/30/2023] [Accepted: 07/03/2023] [Indexed: 08/17/2023]
Abstract
Voltage-gated calcium channels (CaV) conduct Ca2+ influx promoting neurotransmitters and hormone release. CaV are finely regulated by voltage-dependent and independent pathways either by G-protein-coupled receptors (GPCRs) or intramembrane lipids, respectively, in neurons and glands. Interestingly, pancreatic β-cells are abundantly innervated by both sympathetic and parasympathetic neurons, while a variety of high-voltage activated (HVA) Ca2+ channels are present in these cells. Thus, autonomic system seems to exert a tonic inhibition on HVA Ca2+ channels throughout GPCRs, constitutively preventing hormone secretion. Therefore, this work aimed to investigate noradrenergic and cholinergic inhibition of HVA Ca2+ channels in pancreatic β-cells. Experiments were conducted in pancreatic β-cells of rat by using patch-clamping methods, immunocytochemistry, pharmacological probes, and biochemical reagents. A voltage-clamp protocol with a strong depolarizing prepulse was used to unmask tonic inhibition. Herein, we consistently find a basal tonic inhibition of HVA Ca2+ channels according to a GPCRs regulation. Facilitation ratio is enhanced by noradrenaline (NA) according to a voltage-dependent regulation and a membrane-delimited mechanism, while no facilitation changes are observed with carbachol or phosphatidylinositol 4,5-bisphosphate (PIP2). Furthermore, carbachol or intramembrane lipids, such as PIP2, do not change facilitation ratio according to a voltage-independent regulation. Together, HVA Ca2+ channels of pancreatic β-cells are constitutively inhibited by GPCRs, suggesting a natural brake preventing cells from exhaustive insulin secretion.NEW & NOTEWORTHY Our results support the hypothesis that GPCRs tonically inhibit HVA Ca2+ channels in pancreatic β-cells. A voltage-clamp protocol with a strong depolarizing prepulse was used to unmask voltage-dependent inhibition of Ca2+ channels. The novelty of these results strengthens the critical role of Gβγ's in Ca2+ channel regulation, highlighting kinetic slowing and increased facilitation ratio. Together, HVA Ca2+ channels of pancreatic β-cells are constitutively inhibited by GPCRs underlying fine-tuning modulation of insulin secretion.
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Affiliation(s)
- Tayde Quiroz-Acosta
- Department of Physiology, Faculty of Medicine, Universidad Nacional Autónoma de México, UNAM, Ciudad de México, Mexico
| | - Karina Bermeo
- Department of Physiology, Faculty of Medicine, Universidad Nacional Autónoma de México, UNAM, Ciudad de México, Mexico
| | - Isabel Arenas
- Department of Physiology, Faculty of Medicine, Universidad Nacional Autónoma de México, UNAM, Ciudad de México, Mexico
| | - David E Garcia
- Department of Physiology, Faculty of Medicine, Universidad Nacional Autónoma de México, UNAM, Ciudad de México, Mexico
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4
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Differential Regulation of Prelimbic and Thalamic Transmission to the Basolateral Amygdala by Acetylcholine Receptors. J Neurosci 2023; 43:722-735. [PMID: 36535767 PMCID: PMC9899087 DOI: 10.1523/jneurosci.2545-21.2022] [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: 12/28/2021] [Revised: 12/12/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
The amygdalar anterior basolateral nucleus (BLa) plays a vital role in emotional behaviors. This region receives dense cholinergic projections from basal forebrain which are critical in regulating neuronal activity in BLa. Cholinergic signaling in BLa has also been shown to modulate afferent glutamatergic inputs to this region. However, these studies, which have used cholinergic agonists or prolonged optogenetic stimulation of cholinergic fibers, may not reflect the effect of physiological acetylcholine release in the BLa. To better understand these effects of acetylcholine, we have used electrophysiology and optogenetics in male and female mouse brain slices to examine cholinergic regulation of afferent BLa input from cortex and midline thalamic nuclei. Phasic ACh release evoked by single pulse stimulation of cholinergic terminals had a biphasic effect on transmission at cortical input, producing rapid nicotinic receptor-mediated facilitation followed by slower mAChR-mediated depression. In contrast, at this same input, sustained ACh elevation through application of the cholinesterase inhibitor physostigmine suppressed glutamatergic transmission through mAChRs only. This suppression was not observed at midline thalamic nuclei inputs to BLa. In agreement with this pathway specificity, the mAChR agonist, muscarine more potently suppressed transmission at inputs from prelimbic cortex than thalamus. Muscarinic inhibition at prelimbic cortex input required presynaptic M4 mAChRs, while at thalamic input it depended on M3 mAChR-mediated stimulation of retrograde endocannabinoid signaling. Muscarinic inhibition at both pathways was frequency-dependent, allowing only high-frequency activity to pass. These findings demonstrate complex cholinergic regulation of afferent input to BLa that is pathway-specific and frequency-dependent.SIGNIFICANCE STATEMENT Cholinergic modulation of the basolateral amygdala regulates formation of emotional memories, but the underlying mechanisms are not well understood. Here, we show, using mouse brain slices, that ACh differentially regulates afferent transmission to the BLa from cortex and midline thalamic nuclei. Fast, phasic ACh release from a single optical stimulation biphasically regulates glutamatergic transmission at cortical inputs through nicotinic and muscarinic receptors, suggesting that cholinergic neuromodulation can serve precise, computational roles in the BLa. In contrast, sustained ACh elevation regulates cortical input through muscarinic receptors only. This muscarinic regulation is pathway-specific with cortical input inhibited more strongly than midline thalamic nuclei input. Specific targeting of these cholinergic receptors may thus provide a therapeutic strategy to bias amygdalar processing and regulate emotional memory.
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5
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Staali L, Colin DA. Bi-component HlgC/HlgB and HlgA/HlgB γ-hemolysins from S. aureus: Modulation of Ca 2+ channels activity through a differential mechanism. Toxicon 2021; 201:74-85. [PMID: 34411591 DOI: 10.1016/j.toxicon.2021.08.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/21/2021] [Accepted: 08/10/2021] [Indexed: 10/20/2022]
Abstract
Staphylococcal bi-component leukotoxins known as *pore-forming toxins* induce upon a specific binding to membrane receptors, two independent cellular events in human neutrophils. First, they provoke the opening of pre-existing specific ionic channels including Ca2+ channels. Then, they form membrane pores specific to monovalent cations leading to immune cells death. Among these leukotoxins, HlgC/HlgB and HlgA/HlgB γ-hemolysins do act in synergy to induce the opening of different types of Ca2+ channels in the absence as in the presence of extracellular Ca2+. Here, we investigate the mechanism underlying the modulation of Ca2+-independent Ca2+ channels in response to both active leukotoxins in human neutrophils. In the absence of extracellular Ca2+, the Mn2+ has been used as a Ca2+ surrogate to determine the activity of Ca2+-independent Ca2+ channels. Our findings provide new insights about different mechanisms involved in the staphylococcal γ-hemolysins activity to regulate three different types of Ca2+-independent Ca2+ channels. We conclude that (i) HlgC/HlgB stimulates the opening of La3+-sensitive Ca2+ channels, through a cholera toxin-sensitive G protein, (ii) HlgA/HlgB stimulates the opening of Ca2+ channels not sensitive to La3+, through a G protein-independent process, and (iii) unlike HlgA/HlgB, HlgC/HlgB toxins prevent the opening of a new type of Ca2+ channels by phosphorylation/de-phosphorylation-dependent mechanisms.
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Affiliation(s)
- Leila Staali
- Bacteriology Institute of Medical Faculty, Louis Pasteur University, 3 rue Koeberlé, F-67000, Strasbourg, France.
| | - Didier A Colin
- Bacteriology Institute of Medical Faculty, Louis Pasteur University, 3 rue Koeberlé, F-67000, Strasbourg, France
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6
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Ravi B, Zhao J, Chaudhry I, Signorelli R, Bartole M, Kopchock RJ, Guijarro C, Kaplan JM, Kang L, Collins KM. Presynaptic Gαo (GOA-1) signals to depress command neuron excitability and allow stretch-dependent modulation of egg laying in Caenorhabditis elegans. Genetics 2021; 218:6284136. [PMID: 34037773 DOI: 10.1093/genetics/iyab080] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/18/2021] [Indexed: 12/29/2022] Open
Abstract
Egg laying in the nematode worm Caenorhabditis elegans is a two-state behavior modulated by internal and external sensory input. We have previously shown that homeostatic feedback of embryo accumulation in the uterus regulates bursting activity of the serotonergic HSN command neurons that sustains the egg-laying active state. How sensory feedback of egg release signals to terminate the egg-laying active state is less understood. We find that Gαo, a conserved Pertussis Toxin-sensitive G protein, signals within HSN to inhibit egg-laying circuit activity and prevent entry into the active state. Gαo signaling hyperpolarizes HSN, reducing HSN Ca2+ activity and input onto the postsynaptic vulval muscles. Loss of inhibitory Gαo signaling uncouples presynaptic HSN activity from a postsynaptic, stretch-dependent homeostat, causing precocious entry into the egg-laying active state when only a few eggs are present in the uterus. Feedback of vulval opening and egg release activates the uv1 neuroendocrine cells which release NLP-7 neuropeptides which signal to inhibit egg laying through Gαo-independent mechanisms in the HSNs and Gαo-dependent mechanisms in cells other than the HSNs. Thus, neuropeptide and inhibitory Gαo signaling maintains a bi-stable state of electrical excitability that dynamically controls circuit activity in response to both external and internal sensory input to drive a two-state behavior output.
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Affiliation(s)
- Bhavya Ravi
- Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL USA 33136.,Department of Biology, University of Miami, Coral Gables, FL USA 33146
| | - Jian Zhao
- Department of Neuroscience, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Department of Molecular Biology, Massachusetts General Hospital, Boston, MA USA 02114
| | - I Chaudhry
- Department of Biology, University of Miami, Coral Gables, FL USA 33146
| | | | - Mattingly Bartole
- Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL USA 33136.,Department of Biology, University of Miami, Coral Gables, FL USA 33146
| | | | | | - Joshua M Kaplan
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA USA 02114
| | - Lijun Kang
- Department of Neuroscience, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Kevin M Collins
- Neuroscience Program, University of Miami Miller School of Medicine, Miami, FL USA 33136.,Department of Biology, University of Miami, Coral Gables, FL USA 33146
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7
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Wang J, Hertz L, Ruppenthal S, El Nemer W, Connes P, Goede JS, Bogdanova A, Birnbaumer L, Kaestner L. Lysophosphatidic Acid-Activated Calcium Signaling Is Elevated in Red Cells from Sickle Cell Disease Patients. Cells 2021; 10:456. [PMID: 33672679 PMCID: PMC7924404 DOI: 10.3390/cells10020456] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 12/15/2022] Open
Abstract
(1) Background: It is known that sickle cells contain a higher amount of Ca2+ compared to healthy red blood cells (RBCs). The increased Ca2+ is associated with the most severe symptom of sickle cell disease (SCD), the vaso-occlusive crisis (VOC). The Ca2+ entry pathway received the name of Psickle but its molecular identity remains only partly resolved. We aimed to map the involved Ca2+ signaling to provide putative pharmacological targets for treatment. (2) Methods: The main technique applied was Ca2+ imaging of RBCs from healthy donors, SCD patients and a number of transgenic mouse models in comparison to wild-type mice. Life-cell Ca2+ imaging was applied to monitor responses to pharmacological targeting of the elements of signaling cascades. Infection as a trigger of VOC was imitated by stimulation of RBCs with lysophosphatidic acid (LPA). These measurements were complemented with biochemical assays. (3) Results: Ca2+ entry into SCD RBCs in response to LPA stimulation exceeded that of healthy donors. LPA receptor 4 levels were increased in SCD RBCs. Their activation was followed by the activation of Gi protein, which in turn triggered opening of TRPC6 and CaV2.1 channels via a protein kinase Cα and a MAP kinase pathway, respectively. (4) Conclusions: We found a new Ca2+ signaling cascade that is increased in SCD patients and identified new pharmacological targets that might be promising in addressing the most severe symptom of SCD, the VOC.
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Affiliation(s)
- Jue Wang
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA;
| | - Laura Hertz
- Theoretical Medicine and Biosciences, Saarland University, 66421 Homburg, Germany;
- Experimental Physics, Dynamics of Fluids, Saarland University, 66123 Saarbrücken, Germany;
| | - Sandra Ruppenthal
- Experimental Physics, Dynamics of Fluids, Saarland University, 66123 Saarbrücken, Germany;
- Gynaecology, Obstetrics and Reproductive Medicine, Saarland University Hospital, 66421 Homburg, Germany
| | - Wassim El Nemer
- Etablissement Français du Sang PACA-Corse, Aix Marseille Université, EFS, CNRS, ADES, 13005 Marseille, France;
- Laboratoire d’Excellence GR-Ex, 75015 Paris, France;
| | - Philippe Connes
- Laboratoire d’Excellence GR-Ex, 75015 Paris, France;
- Laboratory LIBM EA7424, Vascular Biology and Red Blood Cell Teal, University Claude Bernard Lyon 1, 69008 Lyon, France
| | - Jeroen S. Goede
- Division of Oncology and Hematology, Kantonsspital Winterthur, CH-8401 Winterthur, Switzerland;
| | - Anna Bogdanova
- Red Blood Cell Research Group, Institute of Veterinary Physiology, University of Zürich, CH-8057 Zürich, Switzerland;
| | - Lutz Birnbaumer
- Institute of Biomedical Research (BIOMED), Catholic University of Argentina, C1107AFF Buenos Aires, Argentina;
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Lars Kaestner
- Theoretical Medicine and Biosciences, Saarland University, 66421 Homburg, Germany;
- Experimental Physics, Dynamics of Fluids, Saarland University, 66123 Saarbrücken, Germany;
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Input-output signal processing plasticity of vagal motor neurons in response to cardiac ischemic injury. iScience 2021; 24:102143. [PMID: 33665562 PMCID: PMC7898179 DOI: 10.1016/j.isci.2021.102143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/01/2021] [Accepted: 01/29/2021] [Indexed: 11/23/2022] Open
Abstract
Vagal stimulation is emerging as the next frontier in bioelectronic medicine to modulate peripheral organ health and treat disease. The neuronal molecular phenotypes in the dorsal motor nucleus of the vagus (DMV) remain largely unexplored, limiting the potential for harnessing the DMV plasticity for therapeutic interventions. We developed a mesoscale single-cell transcriptomics data from hundreds of DMV neurons under homeostasis and following physiological perturbations. Our results revealed that homeostatic DMV neuronal states can be organized into distinguishable input-output signal processing units. Remote ischemic preconditioning induced a distinctive shift in the neuronal states toward diminishing the role of inhibitory inputs, with concomitant changes in regulatory microRNAs miR-218a and miR-495. Chronic cardiac ischemic injury resulted in a dramatic shift in DMV neuronal states suggestive of enhanced neurosecretory function. We propose a DMV molecular network mechanism that integrates combinatorial neurotransmitter inputs from multiple brain regions and humoral signals to modulate cardiac health.
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9
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Tong R, Pan S, Pan L, Zhang L. Effects of biogenic amines on the immune response and immunoregulation mechanism in hemocytes of Litopenaeus vannamei in vitro. Mol Immunol 2020; 128:1-9. [DOI: 10.1016/j.molimm.2020.09.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/24/2020] [Accepted: 09/28/2020] [Indexed: 02/06/2023]
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10
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Hayes AJ, Melrose J. Electro‐Stimulation, a Promising Therapeutic Treatment Modality for Tissue Repair: Emerging Roles of Sulfated Glycosaminoglycans as Electro‐Regulatory Mediators of Intrinsic Repair Processes. ADVANCED THERAPEUTICS 2020. [DOI: 10.1002/adtp.202000151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Anthony J. Hayes
- Bioimaging Research Hub Cardiff School of Biosciences Cardiff University Cardiff Wales CF10 3AX UK
| | - James Melrose
- Raymond Purves Bone and Joint Research Laboratory Kolling Institute Northern Sydney Local Health District Faculty of Medicine and Health University of Sydney Royal North Shore Hospital St. Leonards NSW 2065 Australia
- Graduate School of Biomedical Engineering University of New South Wales Sydney NSW 2052 Australia
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Castro H, Bermeo K, Arenas I, Garcia DE. Maintenance of Ca V2.2 channel-current by PIP 2 unveiled by neomycin in sympathetic neurons of the rat. Arch Biochem Biophys 2020; 682:108261. [PMID: 31923392 DOI: 10.1016/j.abb.2020.108261] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 12/13/2019] [Accepted: 01/06/2020] [Indexed: 02/01/2023]
Abstract
Membrane lipids are key determinants in the regulation of voltage-gated ion channels. Phosphatidylinositol 4,5-bisphosphate (PIP2), a native membrane phospholipid, has been involved in the maintenance of the current amplitude and in the voltage-independent regulation of voltage-gated calcium channels (VGCC). However, the nature of the PIP2 regulation on VGCC has not been fully elucidated. This work aimed to investigate whether the interacting PIP2 electrostatic charges may account for maintaining the current amplitude of CaV2.2 channels. Furthermore, we tested whether charge shielding of PIP2 mimics the voltage-independent inhibition induced by M1 muscarinic acetylcholine receptor (M1R) activation. Therefore, neomycin, a polycation that has been shown to block electrostatic interactions of PIP2, was intracellularly dialyzed in superior cervical ganglion (SCG) neurons of the rat. Consistently, neomycin time-dependently diminished the calcium current amplitude letting the channel exhibit the hallmarks of the voltage-independent regulation. These results support that interacting PIP2 charges not only underly the maintenance of the channel-current but also that charge screening of PIP2 by itself unveils the voltage-independent features of CaV2.2 channels in SCG neurons.
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Affiliation(s)
- Hector Castro
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70250, C.P. 04510, CdMx, México
| | - Karina Bermeo
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70250, C.P. 04510, CdMx, México
| | - Isabel Arenas
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70250, C.P. 04510, CdMx, México
| | - David E Garcia
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70250, C.P. 04510, CdMx, México.
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13
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Eickelbeck D, Rudack T, Tennigkeit SA, Surdin T, Karapinar R, Schwitalla JC, Mücher B, Shulman M, Scherlo M, Althoff P, Mark MD, Gerwert K, Herlitze S. Lamprey Parapinopsin ("UVLamP"): a Bistable UV-Sensitive Optogenetic Switch for Ultrafast Control of GPCR Pathways. Chembiochem 2019; 21:612-617. [PMID: 31468691 PMCID: PMC7079062 DOI: 10.1002/cbic.201900485] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Indexed: 12/17/2022]
Abstract
Optogenetics uses light‐sensitive proteins, so‐called optogenetic tools, for highly precise spatiotemporal control of cellular states and signals. The major limitations of such tools include the overlap of excitation spectra, phototoxicity, and lack of sensitivity. The protein characterized in this study, the Japanese lamprey parapinopsin, which we named UVLamP, is a promising optogenetic tool to overcome these limitations. Using a hybrid strategy combining molecular, cellular, electrophysiological, and computational methods we elucidated a structural model of the dark state and probed the optogenetic potential of UVLamP. Interestingly, it is the first described bistable vertebrate opsin that has a charged amino acid interacting with the Schiff base in the dark state, that has no relevance for its photoreaction. UVLamP is a bistable UV‐sensitive opsin that allows for precise and sustained optogenetic control of G protein‐coupled receptor (GPCR) pathways and can be switched on, but more importantly also off within milliseconds via lowintensity short light pulses. UVLamP exhibits an extremely narrow excitation spectrum in the UV range allowing for sustained activation of the Gi/o pathway with a millisecond UV light pulse. Its sustained pathway activation can be switched off, surprisingly also with a millisecond blue light pulse, minimizing phototoxicity. Thus, UVLamP serves as a minimally invasive, narrow‐bandwidth probe for controlling the Gi/o pathway, allowing for combinatorial use with multiple optogenetic tools or sensors. Because UVLamP activated Gi/o signals are generally inhibitory and decrease cellular activity, it has tremendous potential for health‐related applications such as relieving pain, blocking seizures, and delaying neurodegeneration.
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Affiliation(s)
- Dennis Eickelbeck
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Till Rudack
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Stefan Alexander Tennigkeit
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Tatjana Surdin
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Raziye Karapinar
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Jan-Claudius Schwitalla
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Brix Mücher
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Maiia Shulman
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Marvin Scherlo
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Philipp Althoff
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Melanie D Mark
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Klaus Gerwert
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
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14
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Song C, Orlandi C, Sutton LP, Martemyanov KA. The signaling proteins GPR158 and RGS7 modulate excitability of L2/3 pyramidal neurons and control A-type potassium channel in the prelimbic cortex. J Biol Chem 2019; 294:13145-13157. [PMID: 31311860 DOI: 10.1074/jbc.ra119.007533] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 07/11/2019] [Indexed: 12/18/2022] Open
Abstract
Stress profoundly affects physiological properties of neurons across brain circuits and thereby increases the risk for depression. However, the molecular and cellular mechanisms mediating these effects are poorly understood. In this study, we report that chronic physical restraint stress in mice decreases excitability specifically in layer 2/3 of pyramidal neurons within the prelimbic subarea of the prefrontal cortex (PFC) accompanied by the induction of depressive-like behavioral states. We found that a complex between G protein-coupled receptor (GPCR) 158 (GPR158) and regulator of G protein signaling 7 (RGS7), a regulatory GPCR signaling node recently discovered to be a key modulator of affective behaviors, plays a key role in controlling stress-induced changes in excitability in this neuronal population. Deletion of GPR158 or RGS7 enhanced excitability of layer 2/3 PFC neurons and prevented the impact of stress. Investigation of the underlying molecular mechanisms revealed that the A-type potassium channel Kv4.2 subunit is a molecular target of the GPR158-RGS7 complex. We further report that GPR158 physically associates with Kv4.2 channel and promotes its function by suppressing inhibitory modulation by cAMP-protein kinase A (PKA)-mediated phosphorylation. Taken together, our observations reveal a critical mechanism that adjusts neuronal excitability in L2/3 pyramidal neurons of the PFC and may thereby modulate the effects of stress on depression.
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Affiliation(s)
- Chenghui Song
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida 33458
| | - Cesare Orlandi
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida 33458
| | - Laurie P Sutton
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida 33458
| | - Kirill A Martemyanov
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida 33458.
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15
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Romer SH, Deardorff AS, Fyffe REW. A molecular rheostat: Kv2.1 currents maintain or suppress repetitive firing in motoneurons. J Physiol 2019; 597:3769-3786. [DOI: 10.1113/jp277833] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/29/2019] [Indexed: 12/26/2022] Open
Affiliation(s)
- Shannon H. Romer
- Neuroscience, Cell Biology & PhysiologyBoonshoft School of MedicineWright State University Fairborn OH 45435 USA
- Oak Ridge Institute for Science and EducationEnvironmental Health Effects LaboratoryNavy Medical Research Unit‐DaytonWright‐Patterson Air Force Base OH 45433 USA
| | - Adam S. Deardorff
- Neuroscience, Cell Biology & PhysiologyBoonshoft School of MedicineWright State University Fairborn OH 45435 USA
- Neurology, Boonshoft School of MedicineWright State University Dayton OH 45409 USA
| | - Robert E. W. Fyffe
- Neuroscience, Cell Biology & PhysiologyBoonshoft School of MedicineWright State University Fairborn OH 45435 USA
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16
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Presynaptic Calcium Channels. Int J Mol Sci 2019; 20:ijms20092217. [PMID: 31064106 PMCID: PMC6539076 DOI: 10.3390/ijms20092217] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/22/2019] [Accepted: 04/26/2019] [Indexed: 12/27/2022] Open
Abstract
Presynaptic Ca2+ entry occurs through voltage-gated Ca2+ (CaV) channels which are activated by membrane depolarization. Depolarization accompanies neuronal firing and elevation of Ca2+ triggers neurotransmitter release from synaptic vesicles. For synchronization of efficient neurotransmitter release, synaptic vesicles are targeted by presynaptic Ca2+ channels forming a large signaling complex in the active zone. The presynaptic CaV2 channel gene family (comprising CaV2.1, CaV2.2, and CaV2.3 isoforms) encode the pore-forming α1 subunit. The cytoplasmic regions are responsible for channel modulation by interacting with regulatory proteins. This article overviews modulation of the activity of CaV2.1 and CaV2.2 channels in the control of synaptic strength and presynaptic plasticity.
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17
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Ma Z, Gao F, Larsen B, Gao M, Luo Z, Chen D, Ma X, Qiu S, Zhou Y, Xie J, Xi ZX, Wu J. Mechanisms of cannabinoid CB 2 receptor-mediated reduction of dopamine neuronal excitability in mouse ventral tegmental area. EBioMedicine 2019; 42:225-237. [PMID: 30952618 PMCID: PMC6491419 DOI: 10.1016/j.ebiom.2019.03.040] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 02/24/2019] [Accepted: 03/14/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND We have recently reported that activation of cannabinoid type 2 receptors (CB2Rs) reduces dopamine (DA) neuron excitability in mouse ventral tegmental area (VTA). Here, we elucidate the underlying mechanisms. METHODS Patch-clamp recordings were performed in mouse VTA slices and dissociated single VTA DA neurons. FINDINGS Using cell-attached recording in VTA slices, bath-application of CB2R agonists (JWH133 or five other CB2R agonists) significantly reduced VTA DA neuron action potential (AP) firing rate. Under the patch-clamp whole-cell recording model, JWH133 (10 μM) mildly reduced the frequency of miniature excitatory postsynaptic currents (mEPSCs) but not miniature inhibitory postsynaptic currents (mIPSCs). JWH133 also did not alter evoked EPSCs or IPSCs. In freshly dissociated VTA DA neurons, JWH133 reduced AP firing rate, delayed AP initiation and enhanced AP after-hyperpolarization. In voltage-clamp recordings, JWH133 (1 μM) enhanced M-type K+ currents and this effect was absent in CB2-/- mice and abolished by co-administration of a selective CB2R antagonist (10 μM, AM630). CB2R-mediated inhibition in VTA DA neuron firing can be mimicked by M-current opener (10 μM retigabine) and blocked by M-current blocker (30 μM XE991). In addition, enhancement of neuronal cAMP by forskolin (10 μM) reduced M-current and increased DA neuron firing rate. Finally, pharmacological block of synaptic transmission by NBQX (10 μM), D-APV (50 μM) and picrotoxin (100 μM) in VTA slices failed to prevent CB2R-mediated inhibition, while intracellular infusion of guanosine 5'-O-2-thiodiphosphate (600 μM, GDP-β-S) through recording electrode to block postsynaptic G-protein function prevented JWH133-induced reduction in AP firing. INTERPRETATION Our results suggest that CB2Rs modulate VTA DA neuron excitability mainly through an intrinsic mechanism, including a CB2R-mediated reduction of intracellular cAMP, and in turn enhancement of M-type K+ currents. FUND: This research was supported by the Barrow Neuroscience Foundation, the BNI-BMS Seed Fund, and CNSF (81771437).
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Affiliation(s)
- Zegang Ma
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao 266071, China; Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA
| | - Fenfei Gao
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong 210854, China; Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA
| | - Brett Larsen
- Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA; Department of Basic Medical Sciences, University of Arizona College of Medicine, Phoenix, AZ 85004, USA
| | - Ming Gao
- Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA
| | - Zhihua Luo
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong 210854, China
| | - Dejie Chen
- Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA; Department of Neurology, Yunfu People's Hospital, Yunfu, Guangdong 527300, China
| | - Xiaokuang Ma
- Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA; Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong 210854, China; Department of Basic Medical Sciences, University of Arizona College of Medicine, Phoenix, AZ 85004, USA
| | - Shenfeng Qiu
- Department of Basic Medical Sciences, University of Arizona College of Medicine, Phoenix, AZ 85004, USA
| | - Yu Zhou
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao 266071, China
| | - Junxia Xie
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao 266071, China
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD 21224, USA
| | - Jie Wu
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, Shandong Provincial Collaborative Innovation Center for Neurodegenerative Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao 266071, China; Department of Neurobiology, St. Joseph's Hospital and Medical Center, Barrow Neurological Institute, Phoenix, AZ 85013, USA; Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong 210854, China; Department of Neurology, Yunfu People's Hospital, Yunfu, Guangdong 527300, China.
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18
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Melrose J. Functional Consequences of Keratan Sulfate Sulfation in Electrosensory Tissues and in Neuronal Regulation. ACTA ACUST UNITED AC 2019; 3:e1800327. [PMID: 32627425 DOI: 10.1002/adbi.201800327] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/16/2019] [Indexed: 12/20/2022]
Abstract
Keratan sulfate (KS) is a functional electrosensory and neuro-instructive molecule. Recent studies have identified novel low sulfation KS in auditory and sensory tissues such as the tectorial membrane of the organ of Corti and the Ampullae of Lorenzini in elasmobranch fish. These are extremely sensitive proton gradient detection systems that send signals to neural interfaces to facilitate audition and electrolocation. High and low sulfation KS have differential functional roles in song learning in the immature male zebra song-finch with high charge density KS in song nuclei promoting brain development and cognitive learning. The conductive properties of KS are relevant to the excitable neural phenotype. High sulfation KS interacts with a large number of guidance and neuroregulatory proteins. The KS proteoglycan microtubule associated protein-1B (MAP1B) stabilizes actin and tubulin cytoskeletal development during neuritogenesis. A second 12 span transmembrane synaptic vesicle associated KS proteoglycan (SV2) provides a smart gel storage matrix for the storage of neurotransmitters. MAP1B and SV2 have prominent roles to play in neuroregulation. Aggrecan and phosphacan have roles in perineuronal net formation and in neuroregulation. A greater understanding of the biology of KS may be insightful as to how neural repair might be improved.
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Affiliation(s)
- James Melrose
- Raymond Purves Bone and Joint Research Laboratories, Kolling Institute of Medical Research, Royal North Shore Hospital and University of Sydney, St. Leonards, NSW, 2065, Australia.,Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2052, Australia.,Sydney Medical School, Northern, Sydney University, Royal North Shore Hospital, St. Leonards, NSW, 2065, Australia.,Faculty of Medicine and Health, University of Sydney, Royal North Shore Hospital, St. Leonards, NSW, 2065, Australia
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19
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Abstract
Modulation of neurotransmitter exocytosis by activated Gi/o coupled G-protein coupled receptors (GPCRs) is a universal regulatory mechanism used both to avoid overstimulation and to influence circuitry. One of the known modulation mechanisms is the interaction between Gβγ and the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNAREs). There are 5 Gβ and 12 Gγ subunits, but specific Gβγs activated by a given GPCR and the specificity to effectors, such as SNARE, in vivo are not known. Although less studied, Gβγ binding to the exocytic fusion machinery (i.e. SNARE) provides a more direct regulatory mechanism for neurotransmitter release. Here, we review some recent insights in the architecture of the synaptic terminal, modulation of synaptic transmission, and implications of G protein modulation of synaptic transmission in diseases. Numerous presynaptic proteins are involved in the architecture of synaptic terminals, particularly the active zone, and their importance in the regulation of exocytosis is still not completely understood. Further understanding of the Gβγ-SNARE interaction and the architecture and mechanisms of exocytosis may lead to the discovery of novel therapeutic targets to help patients with various disorders such as hypertension, attention-deficit/hyperactivity disorder, post-traumatic stress disorder, and acute/chronic pain.
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Affiliation(s)
- Yun Young Yim
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States
| | - Zack Zurawski
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States
| | - Heidi Hamm
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States.
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20
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Selective tracking of FFAR3-expressing neurons supports receptor coupling to N-type calcium channels in mouse sympathetic neurons. Sci Rep 2018; 8:17379. [PMID: 30478340 PMCID: PMC6255804 DOI: 10.1038/s41598-018-35690-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 11/08/2018] [Indexed: 12/30/2022] Open
Abstract
Activation of short-chain free fatty acid receptors 3 (FFAR3) has been suggested to promote sympathetic outflow in postganglionic sympathetic neurons or hamper it by a negative coupling to N-type calcium (CaV2.2) channels. Heterogeneity of FFAR3 expression in sympathetic neurons, however, renders single neurons studies extremely time-consuming in wild-type mice. Previous studies demonstrated large variability of the degree of CaV2.2 channel inhibition by FFAR3 in a global population of rat sympathetic neurons. Therefore, we focused on a small subpopulation of mouse sympathetic neurons using an FFAR3 antibody and an Ffar3 reporter mouse to perform immunofluorescent and electrophysiological studies. Whole-cell patch-clamp recordings of identified FFAR3-expressing neurons from reporter mice revealed a 2.5-fold decrease in the CaV2.2-FFAR3 inhibitory coupling variability and 1.5-fold increase in the mean ICa2+ inhibition, when compared with unlabeled neurons from wild-type mice. Further, we found that the ablation of Ffar3 gene expression in two knockout mouse models led to a complete loss-of-function. Subpopulations of sympathetic neurons are associated with discrete functional pathways. However, little is known about the neural pathways of the FFAR3-expressing subpopulation. Our data indicate that FFAR3 is expressed primarily in neurons with a vasoconstrictor phenotype. Thus, fine-tuning of chemically-coded neurotransmitters may accomplish an adequate outcome.
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21
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Mato S, Pilar-Cuéllar F, Valdizán EM, González-Maeso J, Rodríguez-Puertas R, Meana J, Sallés J, Crespo-Facorro B, Pazos Á. Selective up-regulation of cannabinoid CB 1 receptor coupling to Go-proteins in suicide victims with mood disorders. Biochem Pharmacol 2018; 157:258-265. [PMID: 30099006 PMCID: PMC6263149 DOI: 10.1016/j.bcp.2018.08.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/08/2018] [Indexed: 01/11/2023]
Abstract
Brain endocannabinoid system is proposed to play a role in the pathogenesis of affective disorders. In the present study, we analyzed the functionality of the cannabinoid receptor type 1 (CB1 receptor) at different transduction levels in prefrontal cortex (PFC) of depressed suicide victims. We examined stimulation of [35S]GTPγS binding, activation of Gα protein subunits and inhibition of adenylyl cyclase by the cannabinoid agonist WIN55,212-2, as well as [3H]CP55,940 binding, in PFC homogenates from suicide victims with major depression (MD) and matched control subjects. CB1 receptor-stimulated [35S]GTPγS binding was significantly greater in the PFC of MD compared with matched controls (23%, p < 0.05). This increase was most evident in the PFC from MD subgroup with negative blood test for antidepressants (AD) at the time of death (AD-free) (38%, p < 0.05), being absent when comparing the AD-treated MD cases with their controls. The density of CB1 receptors and their coupling to adenylyl cyclase were similar between MD and control cases, regardless of the existence of AD intake. Analysis of [35S]GTPγS-labelled Gα subunits allowed for the detection of upregulated CB1 receptor coupling to Gαo, but not to Gαi1, Gαi2, Gαi3, Gαz subunits, in the PFC from AD-free MD suicides. These results suggest that increased CB1 receptor functionality at the Gαi/o protein level in the PFC of MD subjects is due to enhanced coupling to Gαo proteins and might be modulated by AD intake. These data provide new insights into the role of endocannabinoid neurotransmission in the pathobiology of MD and suggest its regulation by ADs.
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Affiliation(s)
- Susana Mato
- Department of Physiology and Pharmacology, University of Cantabria, E-39011 Santander, Spain
| | - Fuencisla Pilar-Cuéllar
- Department of Physiology and Pharmacology, University of Cantabria, E-39011 Santander, Spain; Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), E-39011 Santander, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), E-28029 Madrid, Spain
| | - Elsa M Valdizán
- Department of Physiology and Pharmacology, University of Cantabria, E-39011 Santander, Spain; Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), E-39011 Santander, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), E-28029 Madrid, Spain
| | - Javier González-Maeso
- Department of Pharmacology, University of the Basque Country UPV/EHU, E-48940 Leioa, Spain
| | | | - Javier Meana
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), E-28029 Madrid, Spain; Department of Pharmacology, University of the Basque Country UPV/EHU, E-48940 Leioa, Spain
| | - Joan Sallés
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), E-28029 Madrid, Spain; Department of Pharmacology, University of the Basque Country UPV/EHU, E-48940 Leioa, Spain
| | - Benedicto Crespo-Facorro
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), E-28029 Madrid, Spain; Hospital Universitario Marqués de Valdecilla, University of Cantabria-IDIVAL, School of Medicine, Department of Psychiatry, Santander, Spain
| | - Ángel Pazos
- Department of Physiology and Pharmacology, University of Cantabria, E-39011 Santander, Spain; Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), E-39011 Santander, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), E-28029 Madrid, Spain.
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22
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Kwon OS, Song HS, Park TH, Jang J. Conducting Nanomaterial Sensor Using Natural Receptors. Chem Rev 2018; 119:36-93. [DOI: 10.1021/acs.chemrev.8b00159] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oh Seok Kwon
- Bionanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Republic of Korea
- Nanobiotechnology and Bioinformatics (Major), University of Science & Technology (UST), Daejon 34141, Republic of Korea
| | - Hyun Seok Song
- Sensor System Research Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Division of Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Cheongju 28119, Republic of Korea
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Tai Hyun Park
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Jyongsik Jang
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
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23
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Roberts-Crowley ML, Rittenhouse AR. Modulation of Ca V1.3b L-type calcium channels by M 1 muscarinic receptors varies with Ca Vβ subunit expression. BMC Res Notes 2018; 11:681. [PMID: 30261922 PMCID: PMC6161362 DOI: 10.1186/s13104-018-3783-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 09/20/2018] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES We examined whether two G protein-coupled receptors (GPCRs), muscarinic M1 receptors (M1Rs) and dopaminergic D2 receptors (D2Rs), utilize endogenously released fatty acid to inhibit L-type Ca2+ channels, CaV1.3. HEK-293 cells, stably transfected with M1Rs, were used to transiently transfect D2Rs and CaV1.3b with different CaVβ-subunits, allowing for whole-cell current measurement from a pure channel population. RESULTS M1R activation with Oxotremorine-M inhibited currents from CaV1.3b coexpressed with α2δ-1 and a β1b, β2a, β3, or β4-subunit. Surprisingly, the magnitude of inhibition was less with β2a than with other CaVβ-subunits. Normalizing currents revealed kinetic changes after modulation with β1b, β3, or β4, but not β2a-containing channels. We then examined if D2Rs modulate CaV1.3b when expressed with different CaVβ-subunits. Stimulation with quinpirole produced little inhibition or kinetic changes for CaV1.3b coexpressed with β2a or β3. However, quinpirole inhibited N-type Ca2+ currents in a concentration-dependent manner, indicating functional expression of D2Rs. N-current inhibition by quinpirole was voltage-dependent and independent of phospholipase A2 (PLA2), whereas a PLA2 antagonist abolished M1R-mediated N-current inhibition. These findings highlight the specific regulation of Ca2+ channels by different GPCRs. Moreover, tissue-specific and/or cellular localization of CaV1.3b with different CaVβ-subunits could fine tune the response of Ca2+ influx following GPCR activation.
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Affiliation(s)
- Mandy L. Roberts-Crowley
- Department of Physiology, Program in Neuroscience, University of Massachusetts Medical School, 55 Lake Ave North, Worcester, MA 01655 USA
| | - Ann R. Rittenhouse
- Department of Physiology, Program in Neuroscience, University of Massachusetts Medical School, 55 Lake Ave North, Worcester, MA 01655 USA
- Department of Microbiology and Physiological Systems, Program in Neuroscience, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605 USA
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Feetham CH, O'Brien F, Barrett-Jolley R. Ion Channels in the Paraventricular Hypothalamic Nucleus (PVN); Emerging Diversity and Functional Roles. Front Physiol 2018; 9:760. [PMID: 30034342 PMCID: PMC6043726 DOI: 10.3389/fphys.2018.00760] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 05/30/2018] [Indexed: 12/11/2022] Open
Abstract
The paraventricular nucleus of the hypothalamus (PVN) is critical for the regulation of homeostatic function. Although also important for endocrine regulation, it has been referred to as the "autonomic master controller." The emerging consensus is that the PVN is a multifunctional nucleus, with autonomic roles including (but not limited to) coordination of cardiovascular, thermoregulatory, metabolic, circadian and stress responses. However, the cellular mechanisms underlying these multifunctional roles remain poorly understood. Neurones from the PVN project to and can alter the function of sympathetic control regions in the medulla and spinal cord. Dysfunction of sympathetic pre-autonomic neurones (typically hyperactivity) is linked to several diseases including hypertension and heart failure and targeting this region with specific pharmacological or biological agents is a promising area of medical research. However, to facilitate future medical exploitation of the PVN, more detailed models of its neuronal control are required; populated by a greater compliment of constituent ion channels. Whilst the cytoarchitecture, projections and neurotransmitters present in the PVN are reasonably well documented, there have been fewer studies on the expression and interplay of ion channels. In this review we bring together an up to date analysis of PVN ion channel studies and discuss how these channels may interact to control, in particular, the activity of the sympathetic system.
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Affiliation(s)
- Claire H Feetham
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Fiona O'Brien
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Richard Barrett-Jolley
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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Ghasemi M, Mehranfard N. Mechanisms underlying anticonvulsant and proconvulsant actions of norepinephrine. Neuropharmacology 2018; 137:297-308. [DOI: 10.1016/j.neuropharm.2018.05.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 05/09/2018] [Accepted: 05/10/2018] [Indexed: 01/02/2023]
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Bothwell MY, Gillette MU. Circadian redox rhythms in the regulation of neuronal excitability. Free Radic Biol Med 2018; 119:45-55. [PMID: 29398284 PMCID: PMC5910288 DOI: 10.1016/j.freeradbiomed.2018.01.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 01/17/2018] [Accepted: 01/22/2018] [Indexed: 02/07/2023]
Abstract
Oxidation-reduction reactions are essential to life as the core mechanisms of energy transfer. A large body of evidence in recent years presents an extensive and complex network of interactions between the circadian and cellular redox systems. Recent advances show that cellular redox state undergoes a ~24-h (circadian) oscillation in most tissues and is conserved across the domains of life. In nucleated cells, the metabolic oscillation is dependent upon the circadian transcription-translation machinery and, vice versa, redox-active proteins and cofactors feed back into the molecular oscillator. In the suprachiasmatic nucleus (SCN), a hypothalamic region of the brain specialized for circadian timekeeping, redox oscillation was found to modulate neuronal membrane excitability. The SCN redox environment is relatively reduced in daytime when neuronal activity is highest and relatively oxidized in nighttime when activity is at its lowest. There is evidence that the redox environment directly modulates SCN K+ channels, tightly coupling metabolic rhythms to neuronal activity. Application of reducing or oxidizing agents produces rapid changes in membrane excitability in a time-of-day-dependent manner. We propose that this reciprocal interaction may not be unique to the SCN. In this review, we consider the evidence for circadian redox oscillation and its interdependencies with established circadian timekeeping mechanisms. Furthermore, we will investigate the effects of redox on ion-channel gating dynamics and membrane excitability. The susceptibility of many different ion channels to modulation by changes in the redox environment suggests that circadian redox rhythms may play a role in the regulation of all excitable cells.
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Affiliation(s)
- Mia Y Bothwell
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Martha U Gillette
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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Simultaneous recording of electrical activity and the underlying ionic currents in NG108-15 cells cultured on gold substrate. Heliyon 2018; 4:e00550. [PMID: 29560462 PMCID: PMC5857624 DOI: 10.1016/j.heliyon.2018.e00550] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 12/28/2017] [Accepted: 02/16/2018] [Indexed: 11/23/2022] Open
Abstract
This paper shows the simultaneous recording of electrical activity and the underlying ionic currents by using a gold substrate to culture NG108-15 cells. Cells grown on two different substrates (plastic Petri dishes and gold substrates) were characterized quantitatively through scanning electron microscopy (SEM) as well as qualitatively by optical and atomic force microscopy (AFM). No significant differences were observed between the surface area of cells cultured on gold substrates and Petri dishes, as indicated by measurements performed on SEM images. We also evaluated the electrophysiological compatibility of the cells through standard patch-clamp experiments by analyzing features such as the resting potential, membrane resistance, ionic currents, etc. Cells grown on both substrates showed no significant differences in their dependency on voltage, as well as in the magnitude of the Na+ and K+ current density; however, cells cultured on the gold substrate showed a lower membrane capacitance when compared to those grown on Petri dishes. By using two separate patch-clamp amplifiers, we were able to record the membrane current with the conventional patch-clamp technique and through the gold substrate simultaneously. Furthermore, the proposed technique allowed us to obtain simultaneous recordings of the electrical activity (such as action potentials firing) and the underlying membrane ionic currents. The excellent conductivity of gold makes it possible to overcome important difficulties found in conventional electrophysiological experiments such as those presented by the resistance of the electrolytic bath solution. We conclude that the technique here presented constitutes a solution to the problem of the simultaneous recording of electrical activity and the underlying ionic currents, which for decades, had been solved only partially.
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Presynaptic calcium channels. Neurosci Res 2018; 127:33-44. [DOI: 10.1016/j.neures.2017.09.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 07/13/2017] [Accepted: 08/23/2017] [Indexed: 12/30/2022]
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Domingues MF, de Assis DR, Piovesan AR, Belo CAD, da Costa JC. Peptide YY (3-36) modulates intracellular calcium through activation of the phosphatidylinositol pathway in hippocampal neurons. Neuropeptides 2018; 67:1-8. [PMID: 29157865 DOI: 10.1016/j.npep.2017.11.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 11/03/2017] [Accepted: 11/05/2017] [Indexed: 10/18/2022]
Abstract
Peptide YY (PYY) belongs to the neuropeptide Y (NPY) family, which also includes the pancreatic polypeptide (PP) and NPY. PYY is secreted by the intestinal L cells, being present in the blood stream in two active forms capable of crossing the blood brain barrier, PYY (1-36) and its cleavage product, PYY (3-36). PYY is a selective agonist for the Y2 receptor (Y2R) and these receptors are abundant in the hippocampus. Here we investigated the mechanisms by which PYY (3-36) regulates intracellular Ca2+ concentrations ([Ca2+]i) in hippocampal neurons by employing a calcium imaging technique in hippocampal cultures. Alterations in [Ca2+]i were detected by changes in the Fluo-4 AM reagent emission. PYY (3-36) significantly increased [Ca2+] from the concentration of 10-11M as compared to the controls (infusion of HEPES-buffered solution (HBS) solution alone). The PYY (3-36)-increase in [Ca2+]i remained unchanged even in Ca2+-free extracellular solutions. Sarcoplasmic/endoplasmic reticulum Ca2+-ATPase pump (SERCA pump) inhibition partially prevent the PYY (3-36)-increase of [Ca2+]i and inositol 1,4,5-triphosphate receptor (IP3R) inhibition also decreased the PYY (3-36)-increase of [Ca2+]i. Taken together, our data strongly suggest that PYY (3-36) mobilizes calcium from the neuronal endoplasmic reticulum (ER) stores towards the cytoplasm. Next, we showed that PYY (3-36) inhibited high K+-induced increases of [Ca2+]i, suggesting that PYY (3-36) could also act by activating G-protein coupled inwardly rectifying potassium K+ channels. Finally, the co-infusion of the Y2 receptor (Y2R) antagonist BIIE0246 with PYY (3-36) abolished the [Ca2+]i increase induced by the peptide, suggesting that PYY (3-36)-induced [Ca2+]i increase in hippocampal neurons occurs via Y2Rs.
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Affiliation(s)
- Michelle Flores Domingues
- Graduate Program in Cellular and Molecular Biology - Center for Biotechnology, Universidade Federal do Rio Grande do Sul, UFRGS, Porto Alegre, Brazil; Brain Institute (BraIns), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Porto Alegre, Brazil
| | - Dênis Reis de Assis
- Brain Institute (BraIns), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Porto Alegre, Brazil
| | - Angela Regina Piovesan
- Graduate Program in Cellular and Molecular Biology - Center for Biotechnology, Universidade Federal do Rio Grande do Sul, UFRGS, Porto Alegre, Brazil; Brain Institute (BraIns), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Porto Alegre, Brazil
| | - Cháriston André Dal Belo
- Brain Institute (BraIns), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Porto Alegre, Brazil; Laboratory of Neurobiology and Toxinology, LANETOX, Universidade Federal do Pampa, UNIPAMPA, São Gabriel, Brazil; Graduate Program in Biological Sciences: Biochemical Toxicology, PPGBTox, Universidade Federal de Santa Maria, UFSM, Santa Maria, Brazil.
| | - Jaderson Costa da Costa
- Brain Institute (BraIns), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Porto Alegre, Brazil
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Thomas JR, Hagen J, Soh D, Lee A. Molecular moieties masking Ca 2+-dependent facilitation of voltage-gated Ca v2.2 Ca 2+ channels. J Gen Physiol 2017; 150:83-94. [PMID: 29208674 PMCID: PMC5749111 DOI: 10.1085/jgp.201711841] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 09/29/2017] [Accepted: 10/27/2017] [Indexed: 01/08/2023] Open
Abstract
Ca2+-dependent facilitation is a positive feedback mechanism that regulates Cav2.1 P/Q-type channels but not closely related Cav2.2 N-type channels. Thomas et al. identify the molecular determinants that distinguish the ability of Cav2.1 and Cav2.2 to undergo Ca2+-dependent facilitation. Voltage-gated Cav2.1 (P/Q-type) Ca2+ channels undergo Ca2+-dependent inactivation (CDI) and facilitation (CDF), both of which contribute to short-term synaptic plasticity. Both CDI and CDF are mediated by calmodulin (CaM) binding to sites in the C-terminal domain of the Cav2.1 α1 subunit, most notably to a consensus CaM-binding IQ-like (IQ) domain. Closely related Cav2.2 (N-type) channels display CDI but not CDF, despite overall conservation of the IQ and additional sites (pre-IQ, EF-hand–like [EF] domain, and CaM-binding domain) that regulate CDF of Cav2.1. Here we investigate the molecular determinants that prevent Cav2.2 channels from undergoing CDF. Although alternative splicing of C-terminal exons regulates CDF of Cav2.1, the splicing of analogous exons in Cav2.2 does not reveal CDF. Transfer of sequences encoding the Cav2.1 EF, pre-IQ, and IQ together (EF-pre-IQ-IQ), but not individually, are sufficient to support CDF in chimeric Cav2.2 channels; Cav2.1 chimeras containing the corresponding domains of Cav2.2, either alone or together, fail to undergo CDF. In contrast to the weak binding of CaM to just the pre-IQ and IQ of Cav2.2, CaM binds to the EF-pre-IQ-IQ of Cav2.2 as well as to the corresponding domains of Cav2.1. Therefore, the lack of CDF in Cav2.2 likely arises from an inability of its EF-pre-IQ-IQ to transduce the effects of CaM rather than weak binding to CaM per se. Our results reveal a functional divergence in the CDF regulatory domains of Cav2 channels, which may help to diversify the modes by which Cav2.1 and Cav2.2 can modify synaptic transmission.
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Affiliation(s)
- Jessica R Thomas
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA.,Interdisciplinary Graduate Program in Neuroscience, University of Iowa, Iowa City, IA
| | - Jussara Hagen
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA
| | - Daniel Soh
- Medical Sciences Program, Boston University, Boston, MA
| | - Amy Lee
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA .,Department of Otolaryngology Head-Neck Surgery, University of Iowa, Iowa City, IA.,Department of Neurology, University of Iowa, Iowa City, IA
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Brown DA. Regulation of neural ion channels by muscarinic receptors. Neuropharmacology 2017; 136:383-400. [PMID: 29154951 DOI: 10.1016/j.neuropharm.2017.11.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 10/26/2017] [Accepted: 11/13/2017] [Indexed: 12/20/2022]
Abstract
The excitable behaviour of neurons is determined by the activity of their endogenous membrane ion channels. Since muscarinic receptors are not themselves ion channels, the acute effects of muscarinic receptor stimulation on neuronal function are governed by the effects of the receptors on these endogenous neuronal ion channels. This review considers some principles and factors determining the interaction between subtypes and classes of muscarinic receptors with neuronal ion channels, and summarizes the effects of muscarinic receptor stimulation on a number of different channels, the mechanisms of receptor - channel transduction and their direct consequences for neuronal activity. Ion channels considered include potassium channels (voltage-gated, inward rectifier and calcium activated), voltage-gated calcium channels, cation channels and chloride channels. This article is part of the Special Issue entitled 'Neuropharmacology on Muscarinic Receptors'.
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Affiliation(s)
- David A Brown
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.
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32
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Yano H, Sánchez-Soto M, Ferré S. Bioluminescence Resonance Energy Transfer Assay to Characterize Gi-Like G Protein Subtype-Dependent Functional Selectivity. ACTA ACUST UNITED AC 2017; 81:5.33.1-5.33.13. [PMID: 29058771 DOI: 10.1002/cpns.38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
G protein-coupled receptors (GPCRs) comprise the single most targeted protein class in pharmacology. G protein signaling transduces extracellular stimuli such as neurotransmitters into cellular responses. Although preference for a specific GPCR among different G protein families (e.g., Gs-, Gi-, or Gq-like proteins) is often well studied, preference for a specific G protein subtype (e.g., Gi1, Gi2, Gi3, Go1, and Go2) has received little attention. Due to tissue expression differences and potentially exploitable functional differences, G protein subtype-dependent functional selectivity is an attractive framework to expand GPCR drug development. Herein we present a bioluminescence resonance energy transfer (BRET)-based method to characterize functional selectivity among Gi-like protein subtypes. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Hideaki Yano
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, Maryland
| | - Marta Sánchez-Soto
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, Maryland
| | - Sergi Ferré
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, Maryland
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Kirchner MK, Foehring RC, Wang L, Chandaka GK, Callaway JC, Armstrong WE. Phosphatidylinositol 4,5-bisphosphate (PIP 2 ) modulates afterhyperpolarizations in oxytocin neurons of the supraoptic nucleus. J Physiol 2017; 595:4927-4946. [PMID: 28383826 DOI: 10.1113/jp274219] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 04/04/2017] [Indexed: 01/19/2023] Open
Abstract
KEY POINTS Afterhyperpolarizations (AHPs) generated by repetitive action potentials in supraoptic magnocellular neurons regulate repetitive firing and spike frequency adaptation but relatively little is known about PIP2 's control of these AHPs. We examined how changes in PIP2 levels affected AHPs, somatic [Ca2+ ]i , and whole cell Ca2+ currents. Manipulations of PIP2 levels affected both medium and slow AHP currents in oxytocin (OT) neurons of the supraoptic nucleus. Manipulations of PIP2 levels did not modulate AHPs by influencing Ca2+ release from IP3 -triggered Ca2+ stores, suggesting more direct modulation of channels by PIP2 . PIP2 depletion reduced spike-evoked Ca2+ entry and voltage-gated Ca2+ currents. PIP2 appears to influence AHPs in OT neurons by reducing Ca2+ influx during spiking. ABSTRACT Oxytocin (OT)- and vasopressin (VP)-secreting magnocellular neurons of the supraoptic nucleus (SON) display calcium-dependent afterhyperpolarizations (AHPs) following a train of action potentials that are critical to shaping the firing patterns of these cells. Previous work demonstrated that the lipid phosphatidylinositol 4,5-bisphosphate (PIP2 ) enabled the slow AHP component (sAHP) in cortical pyramidal neurons. We investigated whether this phenomenon occurred in OT and VP neurons of the SON. Using whole cell recordings in coronal hypothalamic slices from adult female rats, we demonstrated that inhibition of PIP2 synthesis with wortmannin robustly blocked both the medium and slow AHP currents (ImAHP and IsAHP ) of OT, but not VP neurons with high affinity. We further tested this by introducing a water-soluble PIP2 analogue (diC8 -PIP2 ) into neurons, which in OT neurons not only prevented wortmannin's inhibitory effect, but slowed rundown of the ImAHP and IsAHP . Inhibition of phospholipase C (PLC) with U73122 did not inhibit either ImAHP or IsAHP in OT neurons, consistent with wortmannin's effects not being due to reducing diacylglycerol (DAG) or IP3 availability, i.e. PIP2 modulation of AHPs is not likely to involve downstream Ca2+ release from inositol 1,4,5-trisphosphate (IP3 )-triggered Ca2+ -store release, or channel modulation via DAG and protein kinase C (PKC). We found that wortmannin reduced [Ca2+ ]i increase induced by spike trains in OT neurons, but had no effect on AHPs evoked by uncaging intracellular Ca2+ . Finally, wortmannin selectively reduced whole cell Ca2+ currents in OT neurons while leaving VP neurons unaffected. The results indicate that PIP2 modulates both the ImAHP and IsAHP in OT neurons, most likely by controlling Ca2+ entry through voltage-gated Ca2+ channels opened during spike trains.
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Affiliation(s)
- Matthew K Kirchner
- Department of Anatomy and Neurobiology and Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Robert C Foehring
- Department of Anatomy and Neurobiology and Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Lie Wang
- Department of Anatomy and Neurobiology and Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Giri Kumar Chandaka
- Department of Anatomy and Neurobiology and Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Joseph C Callaway
- Department of Anatomy and Neurobiology and Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
| | - William E Armstrong
- Department of Anatomy and Neurobiology and Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
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Durdagi S, Erol I, Salmas RE, Patterson M, Noskov SY. First universal pharmacophore model for hERG1 K + channel activators: acthER. J Mol Graph Model 2017; 74:153-170. [PMID: 28499268 DOI: 10.1016/j.jmgm.2017.03.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 03/28/2017] [Accepted: 03/29/2017] [Indexed: 01/31/2023]
Abstract
The intra-cavitary drug blockade of hERG1 channel has been extensively studied, both experimentally and theoretically. Structurally diverse ligands inadvertently block the hERG1 K+ channel currents lead to drug induced Long QT Syndrome (LQTS). Accordingly, designing either hERG1 channel openers or current activators, with the potential to target other binding pockets of the channel, has been introduced as a viable approach in modern anti-arrhythmia drug development. However, reports and investigations on the molecular mechanisms underlying activators binding to the hERG1 channel remain sparse and the overall molecular design principles are largely unknown. Most of the hERG1 activators were discovered during mandatory screening for hERG1 blockade. To fill this apparent deficit, the first universal pharmacophore model for hERG1 K+ channel activators was developed using PHASE. 3D structures of 18 hERG1 K+ channel activators and their corresponding measured binding affinity values were used in the development of pharmacophore models. These compounds spanned a range of structurally different chemotypes with moderate variation in binding affinity. A five sites AAHRR (A, hydrogen-bond accepting, H, hydrophobic, R, aromatic) pharmacophore model has shown reasonable high statistical results compared to the other developed more than 1000 hypotheses. This model was used to construct steric and electrostatic contour maps. The predictive power of the model was tested with 3 external test set compounds as true unknowns. Finally, the pharmacophore model was combined with the previously developed receptor-based model of hERG1 K+ channel to develop and screen novel activators. The results are quite striking and it suggests a greater future role for pharmacophore modeling and virtual drug screening simulations in deciphering complex patterns of molecular mechanisms of hERG1 channel openers at the target sites. The developed model is available upon request and it may serve as basis for the synthesis of novel therapeutic hERG1 activators.
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Affiliation(s)
- Serdar Durdagi
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey.
| | - Ismail Erol
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey; Department of Chemistry, Gebze Technical University, Kocaeli, Turkey
| | - Ramin Ekhteiari Salmas
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey
| | - Matthew Patterson
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Sergei Y Noskov
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.
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Neuner SM, Wilmott LA, Hoffmann BR, Mozhui K, Kaczorowski CC. Hippocampal proteomics defines pathways associated with memory decline and resilience in normal aging and Alzheimer's disease mouse models. Behav Brain Res 2017; 322:288-298. [PMID: 27265785 PMCID: PMC5135662 DOI: 10.1016/j.bbr.2016.06.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 05/20/2016] [Accepted: 06/01/2016] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD), the most common form of dementia in the elderly, has no cure. Thus, the identification of key molecular mediators of cognitive decline in AD remains a top priority. As aging is the most significant risk factor for AD, the goal of this study was to identify altered proteins and pathways associated with the development of normal aging and AD memory deficits, and identify unique proteins and pathways that may contribute to AD-specific symptoms. We used contextual fear conditioning to diagnose 8-month-old 5XFAD and non-transgenic (Ntg) mice as having either intact or impaired memory, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to quantify hippocampal membrane proteins across groups. Subsequent analysis detected 113 proteins differentially expressed relative to memory status (intact vs impaired) in Ntg mice and 103 proteins in 5XFAD mice. Thirty-six proteins, including several involved in neuronal excitability and synaptic plasticity (e.g., GRIA1, GRM3, and SYN1), were altered in both normal aging and AD. Pathway analysis highlighted HDAC4 as a regulator of observed protein changes in both genotypes and identified the REST epigenetic regulatory pathway and Gi intracellular signaling as AD-specific pathways involved in regulating the onset of memory deficits. Comparing the hippocampal membrane proteome of Ntg versus AD, regardless of cognitive status, identified 138 differentially expressed proteins, including confirmatory proteins APOE and CLU. Overall, we provide a novel list of putative targets and pathways with therapeutic potential, including a set of proteins associated with cognitive status in normal aging mice or gene mutations that cause AD.
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Affiliation(s)
- Sarah M Neuner
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Lynda A Wilmott
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Brian R Hoffmann
- Department of Medicine, Division of Cardiology and Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, WI, 53226 United States
| | - Khyobeni Mozhui
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, United States
| | - Catherine C Kaczorowski
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, United States.
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Kim YH, Jeong JH, Ahn DS, Chung S. Phospholipase C-dependent hydrolysis of phosphatidylinositol 4,5-bisphosphate underlies agmatine-induced suppression of N-type Ca 2+ channel in rat celiac ganglion neurons. Biochem Biophys Res Commun 2017; 484:342-347. [PMID: 28131838 DOI: 10.1016/j.bbrc.2017.01.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 01/23/2017] [Indexed: 12/27/2022]
Abstract
Agmatine suppresses peripheral sympathetic tone by modulating Cav2.2 channels in peripheral sympathetic neurons. However, the detailed cellular signaling mechanism underlying the agmatine-induced Cav2.2 inhibition remains unclear. Therefore, in the present study, we investigated the electrophysiological mechanism for the agmatine-induced inhibition of Cav2.2 current (ICav2.2) in rat celiac ganglion (CG) neurons. Consistent with previous reports, agmatine inhibited ICav2.2 in a VI manner. The agmatine-induced inhibition of the ICav2.2 current was also almost completely hindered by the blockade of the imidazoline I2 receptor (IR2), and an IR2 agonist mimicked the inhibitory effect of agmatine on ICav2.2, implying involvement of IR2. The agmatine-induced ICav2.2 inhibition was significantly hampered by the blockade of G protein or phospholipase C (PLC), but not by the pretreatment with pertussis toxin. In addition, diC8-phosphatidylinositol 4,5-bisphosphate (PIP2) dialysis nearly completely hampered agmatine-induced inhibition, which became irreversible when PIP2 resynthesis was blocked. These results suggest that in rat peripheral sympathetic neurons, agmatine-induced IR2 activation suppresses Cav2.2 channel voltage-independently, and that the PLC-dependent PIP2 hydrolysis is responsible for the agmatine-induced suppression of the Cav2.2 channel.
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Affiliation(s)
- Young-Hwan Kim
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Ji-Hyun Jeong
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Duck-Sun Ahn
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Seungsoo Chung
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea.
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Park CG, Park Y, Suh BC. The HOOK region of voltage-gated Ca2+ channel β subunits senses and transmits PIP2 signals to the gate. J Gen Physiol 2017; 149:261-276. [PMID: 28087621 PMCID: PMC5299622 DOI: 10.1085/jgp.201611677] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/12/2016] [Accepted: 12/22/2016] [Indexed: 12/12/2022] Open
Abstract
The β subunit of voltage-gated Ca2+ (CaV) channels plays an important role in regulating gating of the α1 pore-forming subunit and its regulation by phosphatidylinositol 4,5-bisphosphate (PIP2). Subcellular localization of the CaV β subunit is critical for this effect; N-terminal-dependent membrane targeting of the β subunit slows inactivation and decreases PIP2 sensitivity. Here, we provide evidence that the HOOK region of the β subunit plays an important role in the regulation of CaV biophysics. Based on amino acid composition, we broadly divide the HOOK region into three domains: S (polyserine), A (polyacidic), and B (polybasic). We show that a β subunit containing only its A domain in the HOOK region increases inactivation kinetics and channel inhibition by PIP2 depletion, whereas a β subunit with only a B domain decreases these responses. When both the A and B domains are deleted, or when the entire HOOK region is deleted, the responses are elevated. Using a peptide-to-liposome binding assay and confocal microscopy, we find that the B domain of the HOOK region directly interacts with anionic phospholipids via polybasic and two hydrophobic Phe residues. The β2c-short subunit, which lacks an A domain and contains fewer basic amino acids and no Phe residues in the B domain, neither associates with phospholipids nor affects channel gating dynamically. Together, our data suggest that the flexible HOOK region of the β subunit acts as an important regulator of CaV channel gating via dynamic electrostatic and hydrophobic interaction with the plasma membrane.
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Affiliation(s)
- Cheon-Gyu Park
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
| | - Yongsoo Park
- Izmir International Biomedicine and Genome Institute (iBG-izmir), Dokuz Eylul University, 35340 Balcova, Izmir, Turkey
| | - Byung-Chang Suh
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea
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38
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Powers RK, Heckman CJ. Synaptic control of the shape of the motoneuron pool input-output function. J Neurophysiol 2017; 117:1171-1184. [PMID: 28053245 DOI: 10.1152/jn.00850.2016] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 12/28/2016] [Accepted: 12/29/2016] [Indexed: 01/14/2023] Open
Abstract
Although motoneurons have often been considered to be fairly linear transducers of synaptic input, recent evidence suggests that strong persistent inward currents (PICs) in motoneurons allow neuromodulatory and inhibitory synaptic inputs to induce large nonlinearities in the relation between the level of excitatory input and motor output. To try to estimate the possible extent of this nonlinearity, we developed a pool of model motoneurons designed to replicate the characteristics of motoneuron input-output properties measured in medial gastrocnemius motoneurons in the decerebrate cat with voltage-clamp and current-clamp techniques. We drove the model pool with a range of synaptic inputs consisting of various mixtures of excitation, inhibition, and neuromodulation. We then looked at the relation between excitatory drive and total pool output. Our results revealed that the PICs not only enhance gain but also induce a strong nonlinearity in the relation between the average firing rate of the motoneuron pool and the level of excitatory input. The relation between the total simulated force output and input was somewhat more linear because of higher force outputs in later-recruited units. We also found that the nonlinearity can be increased by increasing neuromodulatory input and/or balanced inhibitory input and minimized by a reciprocal, push-pull pattern of inhibition. We consider the possibility that a flexible input-output function may allow motor output to be tuned to match the widely varying demands of the normal motor repertoire.NEW & NOTEWORTHY Motoneuron activity is generally considered to reflect the level of excitatory drive. However, the activation of voltage-dependent intrinsic conductances can distort the relation between excitatory drive and the total output of a pool of motoneurons. Using a pool of realistic motoneuron models, we show that pool output can be a highly nonlinear function of synaptic input but linearity can be achieved through adjusting the time course of excitatory and inhibitory synaptic inputs.
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Affiliation(s)
- Randall K Powers
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington; and
| | - Charles J Heckman
- Departments of Physiology, Physical Medicine and Rehabilitation, and Physical Therapy and Human Movement Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois
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Ghafouri S, Fathollahi Y, Semnanian S, Shojaei A, Mirnajafi-Zadeh J. Effects of Low Frequency Stimulation on Spontaneous Inhibitory and Excitatory Post-Synaptic Currents in Hippocampal CA1 Pyramidal Cells of Kindled Rats. CELL JOURNAL 2017; 18:547-555. [PMID: 28042539 PMCID: PMC5086333 DOI: 10.22074/cellj.2016.4721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 02/24/2016] [Indexed: 11/04/2022]
Abstract
OBJECTIVE Low-frequency stimulation (LFS) exerts suppressive effects in kindled animals. It is believed that overstimulated glutamatergic and decreased GABAergic transmission have long been associated with seizure activity. In this study, we investigated the effect of electrical LFS on different parameters of spontaneous excitatory and inhibitory post-synaptic currents (sEPSCs and sIPSCs) in hippocampal CA1 pyramidal cells in kindled animals. MATERIALS AND METHODS In this experimental study, rats were kindled by electrical stimulation of the hippocampal CA1 area in a semi-rapid manner (12 stimulations/day). The animals were considered fully kindled when they showed stage 5 seizures on three consecutive days. One group of animals received LFS 4 times at 30 seconds, 6 hours, 18 and 24 hours following the last kindling stimulation. Each LFS consisted of 4 packages at 5 minutes intervals. Each package of LFS consisted of 200 pulses at 1 Hz and each monophasic square wave pulse duration was 0.1 millisecond. At 2-3 hours post-LFS, acute hippocampal slices were prepared and a whole cell patch clamp recording was performed in all animals to measure the different parameters of sEPSCs and sIPSCs. RESULTS In kindled animals, the inter-event interval (as an index of occurrence) of sEPSCs decreased, whereas sIPSC increased. In addition, the decay time constant of sIPSCs as an index of the duration of its activity decreased compared to the control group. There was no significant difference in other parameters between the kindled and control groups. Application of LFS in kindled animals prevented the observed changes. There was no significant difference between the measured parameters in kindled+LFS and control groups. CONCLUSION LFS application may prevent seizure-induced increase in the occurrence of sEPSCs and seizure-induced decrease in occurrence and activity duration of sIPSCs.
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Affiliation(s)
- Samireh Ghafouri
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Yaghoub Fathollahi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saeed Semnanian
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Amir Shojaei
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
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40
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Lockard MA, Ebert MS, Bargmann CI. Oxytocin mediated behavior in invertebrates: An evolutionary perspective. Dev Neurobiol 2016; 77:128-142. [PMID: 27804275 DOI: 10.1002/dneu.22466] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 09/14/2016] [Accepted: 10/15/2016] [Indexed: 12/31/2022]
Abstract
The molecular and functional conservation of oxytocin-related neuropeptides in behavior is striking. In animals separated by at least 600 million years of evolution, from roundworms to humans, oxytocin homologs play critical roles in the modulation of reproductive behavior and other biological functions. Here, we review the roles of oxytocin in invertebrate behavior from an evolutionary perspective. We begin by tracing the evolution of oxytocin through the invertebrate animal lineages, and then describe common themes in invertebrate behaviors that are mediated by oxytocin-related peptides, including reproductive behavior, learning and memory, food arousal, and predator/prey relationships. Finally, we discuss interesting future directions that have recently become experimentally tractable. Studying oxytocin in invertebrates offers precise insights into the activity of neuropeptides on well-defined neural circuits; the principles that emerge may also be represented in the more complex vertebrate brain. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 128-142, 2017.
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Affiliation(s)
- Meghan A Lockard
- Laboratory of Neural Circuits and Behavior, The Rockefeller University, New York, New York, 10065
| | - Margaret S Ebert
- Laboratory of Neural Circuits and Behavior, The Rockefeller University, New York, New York, 10065
| | - Cornelia I Bargmann
- Laboratory of Neural Circuits and Behavior, The Rockefeller University, New York, New York, 10065.,Howard Hughes Medical Institute, The Rockefeller University, New York, New York, 10065
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41
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Jeon WJ, Dean B, Scarr E, Gibbons A. The Role of Muscarinic Receptors in the Pathophysiology of Mood Disorders: A Potential Novel Treatment? Curr Neuropharmacol 2016; 13:739-49. [PMID: 26630954 PMCID: PMC4759313 DOI: 10.2174/1570159x13666150612230045] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 12/30/2014] [Accepted: 02/28/2015] [Indexed: 12/21/2022] Open
Abstract
The central cholinergic system has been implicated in the pathophysiology of mood disorders. An imbalance in central cholinergic neurotransmitter activity has been proposed to contribute to the manic and depressive episodes typical of these disorders. Neuropharmacological studies into the effects of cholinergic agonists and antagonists on mood state have provided considerable support for this hypothesis. Furthermore, recent clinical studies have shown that the pan-CHRM antagonist, scopolamine, produces rapid-acting antidepressant effects in individuals with either major depressive disorder (MDD) or bipolar disorder (BPD), such as bipolar depression, contrasting the delayed therapeutic response of conventional mood stabilisers and antidepressants. This review presents recent data from neuroimaging, post-mortem and genetic studies supporting the involvement of muscarinic cholinergic receptors (CHRMs), particularly CHRM2, in the pathophysiology of MDD and BPD. Thus, novel drugs that selectively target CHRMs with negligible effects in the peripheral nervous system might produce more rapid and robust clinical improvement in patients with BPD and MDD.
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Affiliation(s)
| | - Brian Dean
- Florey Institute for Neuroscience and Mental Health, 30 Royal Parade, Parkville, Victoria 3052, Australia.
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de la Cruz L, Puente EI, Reyes-Vaca A, Arenas I, Garduño J, Bravo-Martínez J, Garcia DE. PIP2 in pancreatic β-cells regulates voltage-gated calcium channels by a voltage-independent pathway. Am J Physiol Cell Physiol 2016; 311:C630-C640. [PMID: 27488666 DOI: 10.1152/ajpcell.00111.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 07/29/2016] [Indexed: 12/21/2022]
Abstract
Phosphatidylinositol-4,5-bisphosphate (PIP2) is a membrane phosphoinositide that regulates the activity of many ion channels. Influx of calcium primarily through voltage-gated calcium (CaV) channels promotes insulin secretion in pancreatic β-cells. However, whether CaV channels are regulated by PIP2, as is the case for some non-insulin-secreting cells, is unknown. The purpose of this study was to investigate whether CaV channels are regulated by PIP2 depletion in pancreatic β-cells through activation of a muscarinic pathway induced by oxotremorine methiodide (Oxo-M). CaV channel currents were recorded by the patch-clamp technique. The CaV current amplitude was reduced by activation of the muscarinic receptor 1 (M1R) in the absence of kinetic changes. The Oxo-M-induced inhibition exhibited the hallmarks of voltage-independent regulation and did not involve PKC activation. A small fraction of the Oxo-M-induced CaV inhibition was diminished by a high concentration of Ca2+ chelator, whereas ≥50% of this inhibition was prevented by diC8-PIP2 dialysis. Localization of PIP2 in the plasma membrane was examined by transfecting INS-1 cells with PH-PLCδ1, which revealed a close temporal association between PIP2 hydrolysis and CaV channel inhibition. Furthermore, the depletion of PIP2 by a voltage-sensitive phosphatase reduced CaV currents in a way similar to that observed following M1R activation. These results indicate that activation of the M1R pathway inhibits the CaV channel via PIP2 depletion by a Ca2+-dependent mechanism in pancreatic β- and INS-1 cells and thereby support the hypothesis that membrane phospholipids regulate ion channel activity by interacting with ion channels.
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Affiliation(s)
- Lizbeth de la Cruz
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
| | - Erika I Puente
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
| | - Arturo Reyes-Vaca
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
| | - Isabel Arenas
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
| | - Julieta Garduño
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
| | - Jorge Bravo-Martínez
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
| | - David E Garcia
- Department of Physiology, School of Medicine, Universidad Nacional Autónoma de México (UNAM), Mexico, México
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43
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de Lima KA, de Oliveira GLV, Yaochite JNU, Pinheiro DG, de Azevedo JTC, Silva WA, Covas DT, Couri CEB, Simões BP, Voltarelli JC, Oliveira MC, Malmegrim KCR. Transcriptional profiling reveals intrinsic mRNA alterations in multipotent mesenchymal stromal cells isolated from bone marrow of newly-diagnosed type 1 diabetes patients. Stem Cell Res Ther 2016; 7:92. [PMID: 27406064 PMCID: PMC4942931 DOI: 10.1186/s13287-016-0351-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/12/2016] [Accepted: 06/22/2016] [Indexed: 02/07/2023] Open
Abstract
Background Bone marrow multipotent mesenchymal stromal cells (MSCs) are a diverse subset of precursors that contribute to the homeostasis of the hematopoietic niche. MSCs can be isolated and expanded in vitro and have unique immunomodulatory and regenerative properties that make them attractive for the treatment of autoimmune diseases, including type 1 diabetes (T1D). Whether autologous or allogeneic MSCs are more suitable for therapeutic purposes has not yet been established. While autologous MSCs may present abnormal function, allogeneic cells may be recognized and rejected by the host immune system. Thus, studies that investigate biological characteristics of MSCs isolated from T1D patients are essential to guide future clinical applications. Methods Bone marrow-derived MSCs from recently diagnosed type 1 diabetes patients (T1D-MSCs) were compared with those from healthy individuals (C-MSCs) for morphological and immunophenotypic characteristics and for differentiation potential. Bioinformatics approaches allowed us to match absolute and differential gene expression of several adhesion molecules, immune mediators, growth factors, and their receptors involved with hematopoietic support and immunomodulatory properties of MSCs. Finally, the differentially expressed genes were collated for functional pathway enrichment analysis. Results T1D-MSCs and C-MSCs were similar for morphology, immunophenotype, and differentiation potential. Our absolute gene expression results supported previous literature reports, while also detecting new potential molecules related to bone marrow-derived MSC functions. T1D-MSCs showed intrinsic abnormalities in mRNA expression, including the immunomodulatory molecules VCAM-1, CXCL12, HGF, and CCL2. Pathway analyses revealed activation of sympathetic nervous system and JAK STAT signaling in T1D-MSCs. Conclusions Collectively, our results indicate that MSCs isolated from T1D patients present intrinsic transcriptional alterations that may affect their therapeutic potential. However, the implications of these abnormalities in T1D development as well as in the therapeutic efficacy of autologous MSCs require further investigation. Electronic supplementary material The online version of this article (doi:10.1186/s13287-016-0351-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kalil A de Lima
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil. .,Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil. .,, Tenente Catao Roxo, 2501, Monte Alegre, 14051-140, Ribeirao Preto, Sao Paulo, Brazil.
| | - Gislane L V de Oliveira
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Juliana N U Yaochite
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Ceara, Brazil
| | - Daniel G Pinheiro
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Júlia T C de Azevedo
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Wilson Araujo Silva
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Dimas T Covas
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical Medicine, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Carlos E B Couri
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical Medicine, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Belinda P Simões
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical Medicine, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Julio C Voltarelli
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical Medicine, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Maria C Oliveira
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical Medicine, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Kelen C R Malmegrim
- Center for Cell-Based Research, Regional Blood Center of Ribeirao Preto, Ribeirao Preto Medical, University of Sao Paulo, Ribeirao Preto, Brazil.,Department of Clinical, Toxicological and Bromatological Analysis, Faculty of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Brazil
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Kim YH, Jeong JH, Ahn DS, Chung S. Agmatine suppresses peripheral sympathetic tone by inhibiting N-type Ca(2+) channel activity via imidazoline I2 receptor activation. Biochem Biophys Res Commun 2016; 477:406-12. [PMID: 27320860 DOI: 10.1016/j.bbrc.2016.06.086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 06/16/2016] [Indexed: 11/20/2022]
Abstract
Agmatine, a putative endogenous ligand of imidazoline receptors, suppresses cardiovascular function by inhibiting peripheral sympathetic tone. However, the molecular identity of imidazoline receptor subtypes and its cellular mechanism underlying the agmatine-induced sympathetic suppression remains unknown. Meanwhile, N-type Ca(2+) channels are important for the regulation of NA release in the peripheral sympathetic nervous system. Therefore, it is possible that agmatine suppresses NA release in peripheral sympathetic nerve terminals by inhibiting Ca(2+) influx through N-type Ca(2+) channels. We tested this hypothesis by investigating agmatine effect on electrical field stimulation (EFS)-evoked contraction and NA release in endothelium-denuded rat superior mesenteric arterial strips. We also investigated the effect of agmatine on the N-type Ca(2+) current in superior cervical ganglion (SCG) neurons in rats. Our study demonstrates that agmatine suppresses peripheral sympathetic outflow via the imidazoline I2 receptor in rat mesenteric arteries. In addition, the agmatine-induced suppression of peripheral vascular sympathetic tone is mediated by modulating voltage-dependent N-type Ca(2+) channels in sympathetic nerve terminals. These results suggest a potential cellular mechanism for the agmatine-induced suppression of peripheral sympathetic tone. Furthermore, they provide basic and theoretical information regarding the development of new agents to treat hypertension.
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Affiliation(s)
- Young-Hwan Kim
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Ji-Hyun Jeong
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Duck-Sun Ahn
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Seungsoo Chung
- Department of Physiology, Brain Korea 21 Plus Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea.
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45
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Lu VB, Ikeda SR. Strategies for Investigating G-Protein Modulation of Voltage-Gated Ca2+ Channels. Cold Spring Harb Protoc 2016; 2016:2016/5/pdb.top087072. [PMID: 27140924 DOI: 10.1101/pdb.top087072] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
G-protein-coupled receptor modulation of voltage-gated ion channels is a common means of fine-tuning the response of channels to changes in membrane potential. Such modulation impacts physiological processes such as synaptic transmission, and hence therapeutic strategies often directly or indirectly target these pathways. As an exemplar of channel modulation, we examine strategies for investigating G-protein modulation of CaV2.2 or N-type voltage-gated Ca(2+) channels. We focus on biochemical and genetic tools for defining the molecular mechanisms underlying the various forms of CaV2.2 channel modulation initiated following ligand binding to G-protein-coupled receptors.
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Affiliation(s)
- Van B Lu
- Section on Transmitter Signaling, Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892-9411
| | - Stephen R Ikeda
- Section on Transmitter Signaling, Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892-9411
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46
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Spoida K, Eickelbeck D, Karapinar R, Eckhardt T, Mark MD, Jancke D, Ehinger BV, König P, Dalkara D, Herlitze S, Masseck OA. Melanopsin Variants as Intrinsic Optogenetic On and Off Switches for Transient versus Sustained Activation of G Protein Pathways. Curr Biol 2016; 26:1206-12. [PMID: 27068418 DOI: 10.1016/j.cub.2016.03.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/09/2016] [Accepted: 03/01/2016] [Indexed: 10/22/2022]
Abstract
G-protein-coupled receptors (GPCRs) represent the major protein family for cellular modulation in mammals. Therefore, various strategies have been developed to analyze the function of GPCRs involving pharmaco- and optogenetic approaches [1, 2]. However, a tool that combines precise control of the activation and deactivation of GPCR pathways and/or neuronal firing with limited phototoxicity is still missing. We compared the biophysical properties and optogenetic application of a human and a mouse melanopsin variant (hOpn4L and mOpn4L) on the control of Gi/o and Gq pathways in heterologous expression systems and mouse brain. We found that GPCR pathways can be switched on/off by blue/yellow light. The proteins differ in their kinetics and wavelength dependence to activate and deactivate G protein pathways. Whereas mOpn4L is maximally activated by very short light pulses, leading to sustained G protein activation, G protein responses of hOpn4L need longer light pulses to be activated and decline in amplitude. Based on the different biophysical properties, brief light activation of mOpn4L is sufficient to induce sustained neuronal firing in cerebellar Purkinje cells (PC), whereas brief light activation of hOpn4L induces AP firing, which declines in frequency over time. Most importantly, mOpn4L-induced sustained firing can be switched off by yellow light. Based on the biophysical properties, hOpn4L and mOpn4L represent the first GPCR optogenetic tools, which can be used to switch GPCR pathways/neuronal firing on an off with temporal precision and limited phototoxicity. We suggest to name these tools moMo and huMo for future optogenetic applications.
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Affiliation(s)
- Katharina Spoida
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Dennis Eickelbeck
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Raziye Karapinar
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Tobias Eckhardt
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Melanie D Mark
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Dirk Jancke
- Optical Imaging Group, Institut für Neuroinformatik, NB 2/27, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Benedikt Valerian Ehinger
- Institute of Cognitive Science, University of Osnabrück, Albrechtstrasse 28, 49076 Osnabrück, Germany
| | - Peter König
- Institute of Cognitive Science, University of Osnabrück, Albrechtstrasse 28, 49076 Osnabrück, Germany; Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, Germany
| | - Deniz Dalkara
- Sorbonne Universités, UPMC University Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
| | - Olivia A Masseck
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
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47
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Intrinsic plasticity induced by group II metabotropic glutamate receptors via enhancement of high-threshold KV currents in sound localizing neurons. Neuroscience 2016; 324:177-90. [PMID: 26964678 DOI: 10.1016/j.neuroscience.2016.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 02/05/2016] [Accepted: 03/03/2016] [Indexed: 01/18/2023]
Abstract
Intrinsic plasticity has emerged as an important mechanism regulating neuronal excitability and output under physiological and pathological conditions. Here, we report a novel form of intrinsic plasticity. Using perforated patch clamp recordings, we examined the modulatory effects of group II metabotropic glutamate receptors (mGluR II) on voltage-gated potassium (KV) currents and the firing properties of neurons in the chicken nucleus laminaris (NL), the first central auditory station where interaural time cues are analyzed for sound localization. We found that activation of mGluR II by synthetic agonists resulted in a selective increase of the high-threshold KV currents. More importantly, synaptically released glutamate (with reuptake blocked) also enhanced the high-threshold KV currents. The enhancement was frequency-coding region dependent, being more pronounced in low-frequency neurons compared to middle- and high-frequency neurons. The intracellular mechanism involved the Gβγ signaling pathway associated with phospholipase C and protein kinase C. The modulation strengthened membrane outward rectification, sharpened action potentials, and improved the ability of NL neurons to follow high-frequency inputs. These data suggest that mGluR II provides a feedforward modulatory mechanism that may regulate temporal processing under the condition of heightened synaptic inputs.
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He LL, Zhang QF, Wang LC, Dai JX, Wang CH, Zheng LH, Zhou Z. Muscarinic inhibition of nicotinic transmission in rat sympathetic neurons and adrenal chromaffin cells. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0188. [PMID: 26009767 DOI: 10.1098/rstb.2014.0188] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Little is known about the interactions between nicotinic and muscarinic acetylcholine receptors (nAChRs and mAChRs). Here we report that methacholine (MCh), a selective agonist of mAChRs, inhibited up to 80% of nicotine-induced nAChR currents in sympathetic superior cervical ganglion neurons and adrenal chromaffin cells. The muscarine-induced inhibition (MiI) substantially reduced ACh-induced membrane currents through nAChRs and quantal neurotransmitter release. The MiI was time- and temperature-dependent. The slow recovery of nAChR current after washout of MCh, as well as the high value of Q10 (3.2), suggested, instead of a direct open-channel blockade, an intracellular metabotropic process. The effects of GTP-γ-S, GDP-β-S and pertussis toxin suggested that MiI was mediated by G-protein signalling. Inhibitors of protein kinase C (bisindolymaleimide-Bis), protein kinase A (H89) and PIP2 depletion attenuated the MiI, indicating that a second messenger pathway is involved in this process. Taken together, these data suggest that mAChRs negatively modulated nAChRs via a G-protein-mediated second messenger pathway. The time dependence suggests that MiI may provide a novel mechanism for post-synaptic adaptation in all cells/neurons and synapses expressing both types of AChRs.
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Affiliation(s)
- Lin-Ling He
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Quan-Feng Zhang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Lie-Cheng Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Jing-Xia Dai
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Chang-He Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Liang-Hong Zheng
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Zhuan Zhou
- State Key Laboratory of Biomembrane and Membrane Biotechnology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and PKU-IDG/McGovern Institute for Brain Research and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, People's Republic of China
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Puente EI, De la Cruz L, Arenas I, Elias-Viñas D, Garcia DE. Voltage-Independent Inhibition of the Tetrodotoxin-Sensitive Sodium Currents by Oxotremorine and Angiotensin II in Rat Sympathetic Neurons. Mol Pharmacol 2016; 89:476-83. [DOI: 10.1124/mol.115.101931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 02/10/2016] [Indexed: 01/16/2023] Open
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Zhao Q, Pan L, Ren Q, Wang L, Miao J. Effect of salinity on regulation mechanism of neuroendocrine-immunoregulatory network in Litopenaeus vannamei. FISH & SHELLFISH IMMUNOLOGY 2016; 49:396-406. [PMID: 26766179 DOI: 10.1016/j.fsi.2015.12.045] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/29/2015] [Accepted: 12/30/2015] [Indexed: 06/05/2023]
Abstract
The effects of low salinity (transferred from 31‰ to 26‰, 21‰, and 16‰) on the regulation pathways of neuroendocrine-immunoregulatory network were investigated in Litopenaeus vannamei. The results showed that the hormones (corticotrophin-releasing hormone, adrenocorticotropic hormone) and biogenic amines (dopamine, noradrenaline, 5-hydroxytryptamine) concentrations in lower salinity groups increased significantly within 12 h. The gene expression of biogenic amine receptors showed that dopamine receptor D4 and α2 adrenergic receptor in lower salinity groups decreased significantly within 12 h, whereas the 5-HT7 receptor significantly increased within 1d. The second messenger synthetases (adenylyl cyclase, phospholipase C) and the second messengers (cyclic adenosine monophosphate, cyclic guanosine monophosphate) of lower salinity groups shared a similar trend in which adenylyl cyclase and cyclic adenosine monophosphate reached the maximum at 12 h, whereas phospholipase C and cyclic guanosine monophosphate reached the minimum. The immune parameters (total hemocyte count, phenoloxidase activity, phagocytic activity, crustin expression, antibacterial activity, C-type lectin expression, hemagglutinating activity) in lower salinity groups decreased significantly within 12 h. Except for the total hemocyte count, all the parameters recovered to the control levels afterwards. Therefore, it may be concluded that the neuroendocrine-immunoregulatory network plays a principal role in adapting to salinity changes as the main center for sensing the stress and causes immune response in L. vannamei.
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Affiliation(s)
- Qun Zhao
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, PR China
| | - Luqing Pan
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, PR China.
| | - Qin Ren
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, PR China
| | - Lin Wang
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, PR China
| | - Jingjing Miao
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, PR China
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